WO1989002920A1 - Article for inactivation of toxic materials - Google Patents

Abstract

An article for the inactivation of toxic materials is disclosed that is comprised of a solid support carrier to which are bound at least two kinds of receptors. These receptors act upon the target material to bind and degrade it, thus rendering it ineffective against the surface to be protected. The solid carrier is particularly useful in the form of a bandage or sheet that may be draped over equipment, foodstuffs, or personnel. Novel peptides useful in the article are described that can be used as receptors for target toxins.

Description

  
 



   ARTICLE FOR INACTIVATION
 OF TOXIC MATERIALS
 Description   Background   
 It has been shown that healing of wounds may be aided by the topical application of solutions or ointments that contain enzyme preparations. For example, in U.S. Patent. No.   3,639,579,    Urbin describes the use of oxidase ointment for treating hemorrhoids and in U.S. Patent No. 3,940,478, Kurtz describes a proteolytic enzyme solution to potentiate antibiotic treatment. It has also been demonstrated that treatment of open wounds may be improved by impregnating bandages or gauze pads with therapeutic agents, such as antibiotics, proteolytic enzymes, and proteins. For example, in U.S. Patent   tJo.    2,579,367, Curtis describes the use of   'casein    and egg albumin paste to treat burns. In U.S.



  Patent. No. 2,680,701, Cusumano describes gauze impregnated with antibiotics; in U.S. Patent No.



     4,576,817,      Montgomery    and Pellico describe a pad or polymer impregnated with enzymes.



   Others have described compositions in which one or nore chemicals, including enzymes, are bound to support materials for use in the controlled release of the chemicals. For example, in U.S. Patent No.



  3,493,652, Hartman describes an enzyme-impregnated carrier; and in U.S. Patent No. 3,551,556, Kliment  teaches controlled release of antibiotics and other chemotherapeutics from a polymeric carrier.



   Use of selected enzyme and solid supports has, however, been limited to therapeutic applications, such as relieving inflammation, debriding wounds, and alleviating pain. The use of therapeutic methods in the context of decontamination or detoxification is limited and an article effective in protecting and decontaminating surfaces would be of great benefit, particularly for use prophylactically to inactivate toxic materials Such an article would be particularly useful in protecting and decontaminating a variety of surfaces, such as human skin, clothing, and   foodstuff from    a host of environmental, chemical, and industrial toxins.



  Summary of the Invention
 The present invention relates to an article for the inactivation or detoxification of a target ligand, which is a toxic material or disease-causing agent, as well as to methods of making and using the article. The article comprises at least two receptors, both of which bind the target ligand, and a carrier, which is a solid material. The first receptor (referred to as the binding receptor), binds the target ligand and the second receptor (referred to as the degradative receptor), in    addition  <  ,the target ligand, acts upon the target 11  <  ch a manner as to cause its    inactivation, generally by degrading it. A target ligand may become attached to both a binding receptor and a degradative receptor.

  That is, both  types of receptors may be in sufficiently close proximity to one another that a single target ligand interacts with both a binding receptor and a degradative receptor. Alternatively, the two receptors act independently so that each will inactivate a separate target ligand. The present invention alsorelates to the composition of novel peptides, useful in the article, that will serve as receptors. These novel peptides may be produced synthetically or by recombinant DNA procedures.



   In one embodiment, the article of the present invention comprises a first receptor, which is a protein that binds the target ligand, a second receptor that is an enzyme which specifically acts upon the target ligand, resulting in its degradation, and a carrier to which both receptors are affixed. In another embodiment of the present invention, the article is comprised of a solid supporting material, to which is affixed at least two proteinaceous receptors: a first receptor, which specifically binds a toxic material to be inactivated, and a second receptor, which is an enzyme that hydrolyzes the toxic ligand, rendering it inactive.



   In a method of inactivating a toxic material of the present invention, a target ligand, which is generally a toxic material, is brought into contact with both receptors in such a manner that the material is specifically bound by the first receptor, specifically bound by and degraded by the second receptor or both, resulting in inactivation of the material.  



   In the method of producing an article of the present invention, both receptors are affixed to a solid carrier, by being immobilized on its surface(s), incorporated into it as it is produced, or otherwise attached. In one embodiment, a proteinaceous membrane film, such as bovine serum albumin co-polymerized with glutaraldehyde, is impregnated with at least one binding receptor, such as acetylcholinesterase (AchE) and at least one degradative receptor, such as an organophosphorusdegrading enzyme, which degrades the target ligand. The carrier containing the receptors is then further processed into materials, such as bandages, sheets, beads, powders or gels.



  Brief Description of the Drawings
 Figure 1 is a schematic representation of one embodiment of the invention illustrating the use of
AchE as the binding receptor and a hydrolytic enzyme as the degradative receptor.



   Figure 2 is a graphic representation of the rate of hydrolysis of an organophosphorus toxin by free and immobilized rat liver enzyme.



   Figure 3 represents the temporal changes in
AchE protecting activity of BSA-membrane as a function of storage temperature.



   Figure 4 represents the changes in AchE-protecting activity of BSA and PVC-silica membranes as a function of pH.



   Figure 5 represents the changes in
AchE-protecting activity of BSA and PVC-silica membranes.  



   Figure 6 represents the changes in AchE-protecting activity of BSA and PVC-silica membranes immersed in blood solutions of various concentrations and suspended in soil slurries of various concentrations.



  Detailed Description of the Invention
 The present invention relates to an article for use in inactivating a target material, which is generally a toxic material or an invasive microbe, as well as to novel peptides useful in the article, a method of making the article and a method of using the article. The term "inactivate" as used in this regard describes any means by which   a    target ligand is bound, degraded, decomposed or otherwise rendered nontoxic by the receptor ligands. The article and method of using it are particularly valuable in inactivating or detoxifying toxic materials encountered in environmental, chemical, military and industrial settings.

 

   The article of the present invention comprises at least two receptors and a carrier to which the receptors are affixed. One receptor (referred to as a binding receptor) binds a target material, which is referred to herein as a target ligand, which is to be inactivated, and the second receptor (referred to as a degrading receptor) is a substance, such as an enzyme, which degrades the target ligand.



   Receptors which bind the target ligand to be inactivated contain at least one binding site that forms a bond with at least one binding site of the target material. Contact between the binding  receptor and the target ligand results in binding of the target ligand by the receptor. Binding between ligand and receptor may be accomplished, for example, by covalent, ionic or hydrogen bonding or by
Van der Waals forces. The receptor binds the target ligand and eliminates it from further contact with the surface to be protected.



   Binding receptors. suitable for use in the article of the present invention include proteins (such as enzymes), glycoproteins, biological receptors (such as neural receptors), lectins, antibodies and peptides. In one embodiment, at least one esterase protein, such as acetylcholinesterase, aldolase, trypsin, alpha-chymotrypsin, butyrylcholinesterase, alliesterase, alkaline phosphatase, kallikrein or subtilisin, is used. Plant sulfhydryl esterases such as papain, chymopapain, ficin, and bromelain are also useful. Moreover, peptides modelled after the active sites of naturallyoccurring enzymes such as AchE and papain can be used as binding receptors. Such peptides modelled after active sites and receptors such as those described above can be synthesized mechanically or produced using recombinant DNA methodology that is known in the art.

  Examples of methods useful in producing such receptors are described in Carter, P.



  and J. Wells, Engineered Enzyme Specificity by
Substrate-Assisted Catalysis, Science, 237:394-399 (1987); Carter, P., Biochemical Journal, 237:1 (1986); Stewart, J. M. and J.D. Young, Solid Phase
Peptide Synthesis, (2nd ed.), Pierce Chemical Co.,
Rockford, Illinois and Maniatis, T. et al., Molecu  lar Cloning, Cold Spring Harbor, 1982, the teachings   'of    which are incorporated herein by reference.



   Once bound to the binding receptor, a target ligand is acted upon by the degrading receptor, which inactivates the target material, rendering the material ineffective or inactive. The activity of the degrading receptor in rendering the target material ineffective or inactive is referred to as detoxifying the target ligand. The degrading receptor will generally be an enzyme and can act on the target ligand in one or more ways. For example,
 it may bind the target ligand in such a way that the
 susceptible bond is brought into close proximity to the catalytic group on the enzyme's active site.



  The enzyme may combine with the target to form an unstable, and more readily degraded covalent
 intermediate. The enzyme may bring about acid or base catalysis by donating or accepting protons.



  The enzyme may also induce conformational changes in the structure of the target material, making the
 chemical bonds within the target easier to break.



   In the article of this invention, useful degrading receptors include enzymes, such as
 oxidoreductases and hydrolases. In particular,
 enzymes such as carboxylic ester hydrolases, thiolester hydrolases, phosphate monoester hydrolases, amino acid decarboxylases, L-amino acid
 oxidases and D-amino acid oxidases can be used.



   Degrading ligands useful in the article of the present invention can be naturally-occurring (e.g., enzymes isolated from their natural source). They  can also be produced using genetic engineering methods or can be synthesized mechanically.



  Examples of methods useful in producing such ligands are described by P. Carter and J. Wells in
Engineered Enzyme Specificity by Substrate 
Assisted Catalysis, Science, 237:394-399 (1987) and by P. Carter in Biochemical J., 237:1 (1986) and
J.M. Stewart and J.D. Young in Solid Phase Peptide
Synthesis, Second Edition, Pierce Chemical Co.,
Rockford, Illinois (1984), the teachings of which are incorporated herein by reference.



   Any solid material capable of supporting the binding receptor and the degrading receptor, and to which the receptors can be affixed, is suitable for use in the article of the present invention. The solid support can be, for example, in the form of woven fabric (e.g., sheets, bandages,   etc.),    porous foam pads, absorbent membranes, solvent-based porous elastomers, or beads. Alternatively, the binding receptor and the degrading receptor can be affixed onto beads or solid particles, which are and then incorporated into a foam, gel or an aerosol.



   Supports useful in the article can be obtained commercially in the form of silica-impregnated polyvinylchloride supports (product of Amerace
Corp.), vinyl polymer beads, polymeric beads comprised of agarose, dextran, cellulose, vinyl polymers, acrylates, acrylamides, polystyrene-divinylbenzene or polyethers (product of Pierce Chemical
Co., EM Science, Rohm  & Haas Co., Dextran Products
Ltd., Toyo Soda Manufacturing Co., and others), and alumina or silica (glass) beads (product of Aluminum  
Company of America, Universal Adsorbants, ICN
Adsorbants, W.R. Grace  & Co., and others). These materials to which the receptors have been affixed, may be further processed into bandages, cloths, sheets or powders using techniques described below.



   In the article, both the binding and the degrading receptors are affixed to the carrier. In this regard, "affixed" means fixed or fastened in any manner. Thus, for example, the binding receptor and the degrading receptor can be affixed to the surface of the carrier or they can be incorporated into the carrier (e.g., by being impregnated within the interstices of the carrier). The manner in which the two receptors are affixed to the carrier will vary with the type of carrier used.



   The article of this invention is designed in such a way that the carrier to which the receptors are affixed comes into contact with the target ligand. In this context, the term "contact" means the touching, meeting, or juxtaposition of the receptor-bearing carrier and the target material in such a manner that the target material is bound to either one or both of the receptors. That is, the binding receptor and the degrading receptor are affixed to the carrier such that target ligand comes in contact with either the binding receptor, which acts to prevent further entry of the target material into the protected surface, the degrading receptor, which acts to degrade the target material, or both receptors.

  In the case of a solid carrier in the form of a sheet, bandage, or other similar flat object, the carrier containing the binding receptors  and the degradative receptors is draped, wrapped, or otherwise placed over the area (e.g., skin surface, exterior surfaces of boxes containing food or beverage, etc.) to be protected and decontaminated.



  In the case of a carrier which is in the form of beads, gels, foams, or aerosols, the manner in which the article is applied will depend upon the carrier and may involve the use of a sprayer or atomizer to disperse the receptor-impregnated particles.



   The article of this invention provides a means of inactivating toxic material, such as those encountered in an environmental, military, medical, chemical, or industrial context. Toxic materials/ ligands which can be inactivated include, but are not limited to, materials acting as systemic poisons such as pesticides, nerve agents, bacteria, or viruses. The toxin can be in solid or particulate form, as in the case of a bacterium or a particleadsorbed chemical. Alternatively, the toxin can be in a liquid or gaseous phase, such as the organophosphorus compounds DFP (phosphorofluoridic acid bis(l-methylethyl) ester) and GB (methylphosphonofluoridic acid 1-methylethyl ester), or the carbamate compound Carbaryl (l-napthalenol methylcarbamate).

 

   This invention also relates to a method of making the article of the present invention. In one embodiment of this invention, a solid carrier is made by forming a membrane comprised of bovine serum albumin co-polymerized with   glutaraldehyde.    In another embodiment of this invention, macroporous  supports of silica-impregnated polyvinylchloride are used (e.g.,   Macroporous    Plastic Sheets, Amerace
Corp.). In a further embodiment of this invention, solid beads or irregular particles comprised of inorganic material (e.g., alumina or silica) or polymers (e.g.,   agdrose,    cellulose, dextran, acrylate, styrene, and others) are used. In all three situations, acetylcholinesterase can be immobilized onto the carrier-to serve as the binding receptor.

  Preparations of rat liver organophosphorous-degrading enzyme can be immobilized onto the same carrier to serve as the enzymatic receptor.



   Preparation of receptor-containing membranes is described in detail in Example I. Briefly, this is carried out as follows: A mixture of binding receptors, degradative receptors and serum albumin is prepared; the mixture is allowed to polymerize with buffered glutaraldehyde. Preparation of silica-impregnated PVC supports, microporous plastic sheets (MPS), activated by treatment with polyethyleneimine (Amerace Corp.) is described in
Example II. The sheets are coated with glutaraldehyde in solution containing receptors.



   Preparation of a receptor substance-containing bead support is described in Example 3. As described, a predetermined amount of receptor substance is reacted with a preactivated bead in an appropriate buffer for 4 to 24 hours at room temperature.



   The described membranes and MPS preparations can be used directly to bind and destroy toxic target materials, or may be attached to an adhesive  backing or similar material to form a bandage. The receptor substance-containing beads can be used directly for similar applications or formulated as a salve, gel, cream or lotion. In one embodiment of this invention, a two-compartment bag or soft metal tube is used. One compartment contains dry, receptor substance-containing beads and the second compartment contains a gel or foam under pressure.



  For use, a separator between the two compartments is removed or broken. The contents of the two compartments are mixed and the mixture is expelled from the bag or tube through a nozzle onto the surface to be protected.



   The ability of the article of the present invention to   detoxify    skin wounds has been demonstrated and is detailed in Example XI.



   The present invention will now be illustrated by the following examples, which are not to be seen as limiting in any way.



  Example I Preparation of Receptor-Containing
 Membranes
 This example illustrates the preparation of membranes made from receptor-impregnated   glutaraldehyde.    A mixture is prepared containing from 0.1 to l.Og of bovine or human serum albumin and a predetermined amount of receptor substance in 5 to 10 ml of an appropriate buffer at pH 6.5 to 7.5   (e.g.,    0.01 to   O.lM    KH2PO4-K2HPO4 or 0.005 to 0.lm
Tris-HCL containing   O.4M      KCl    and 0.05M NaCI. From  0.1 to 5% (by volume) gluraraldehyde is added to the mixture, which is mixed gently at room temperature for 5 to 30 minutes. After this time, the mixture is spread evenly onto glass plates and allowed to polymerize and age for 10 to 16 hours.

  The resulting membrane is floated off the glass plate using water immersion, and dried. It is stored dry until used. The amounts of albumin, glutaraldehyde and buffer are varied to alter polymerization time and density of the membrane. The amount of receptor substance to be used depends on its purity and binding activity For example, from 0.01 to 200mg of enzymes such as acetylcholinesterase, butylrylcholinesterase, trypsin, alpha-chymotrypsin, subtilisin, papain, and toxic agent hydrolysis enzymes are used.



  Example II Preparation of Receptor-Containing
 Microporous Polymer Sheets
 Microporous plastic sheets (MPS) activated by treatment with polyethyleneimine (product of Amerace   Corp.)    in which 3x3 cm squares of the MPS are welted, are used . Squares (3 x 3 cm) of the
MPS are wetted in 0.05M NaH2PO4-Na2HPO4 buffer (pH 7) for 1 to 5 minutes, and then immersed into a solution of 5% glutaraldehyde (by volume) in the same buffer for 20 to 60 minutes at room temperature.

  After washing, the glutaraldehyde-covered MPS squares are placed into 5 to 10 ml of buffer containing a predetermined amount of receptor substance for 12 to 20 hours at   4 0C.    After this time, the MPS  support (now containing immobilized receptor substance) is washed, dried and stored dry until used
Example III Preparation of Receptor-Containing
 Beads
 A predetermined amount of receptor substance is reacted with a bead at room temperature, under the reaction conditions which depend on the support used.

  For example, 1 to 50 mg of receptor substances such as acetylcholinesterase and the organophosphorus-degrading enzymes from rat liver, squid hepatopancreas, Escherichia coli or   Tetrahymena    thermophilia were each reacted with 20 ml (approx. 5 g) of Reacti-Gel HW-65F, a vinylpolymer based, 30 to 60 micron bead activated with carbonyldiimidazole (Pierce Chemical Co.) in 1M NaHCO3-Na2CO3 buffer, pH 10 for 12 to 18 hours at room temperature. The resulting beads were washed, dried and stored, either wet or dry, until used.

  Other activated supports can also be used, such as carbodiimidazoleactivated agarose, dextran and glass beads (Pierce
Chemical Co.); epoxy-,   N-hydroxysuccinimide-    or cyanogen bromide activated agaroses (Pharmacia Fine
Chemicals and BioRad Laboratories); or epoxyactivated acrylates and hydroxymetacrylates (Rohm
Pharma and Dextran Products).  



  Example IV Ability of Binding Receptor to Protect
 Against Toxic Materials
 This example illustrates the ability of a known amount of binding receptor in the form of a protein or peptide to protect AchE against inhibition by a target ligand.



   Binding receptors are available commercially (Sigma Chemical Co., St. Louis) with purities of 90% or better. No further purification is needed.



  Acetylcholinesterase can also be prepared from electric eel (Electrophorus sp.) electroplax by homogenizing 50g of minced tissue in 1 mM EDTA. The resulting filtrate is centrifuged at 20,000 x g at   4 0C    and the crude membrane preparation homogenized again   for 30    seconds in 100 ml of 2 mM   NaH2PO4. Na2HPO4    (pH7) containing 1M NaCl and 1 mM
EDTA. The supernatant is concentrated on an ultrafiltration membrane and partially purified on a gel-permeation column packed and run in 10 mM   NaHPOa    (pH 7.4) containing   0.1M    NaCl. The ability of a target ligand to bind AchE is assayed by measuring
AchE activity using the colorimetric assay of Ellman et al. or the radiometric assay of Johnson and
Russell. 

  Ellman G.L. et al., Biochemical
Pharmacology, 7:88 (1961); Johnson, D.C. and R.L.



  Russell, Analytical Biochemistry, 64:229 (1975).



  These as says were used to determine AchE activity in the presence and absence of the target ligand and binding receptor.  



   Table 1 shows the percentage protection of AchE in the presence of selected organophosphorus toxins.



  The concentration of the organophosphorus compound was set at an amount equal to the concentration which caused a 50% inhibition in controls containing no protective receptor. Acetylcholinesterase and butyrylcholinesterase (BuchE) provided the greatest protection (i.e., they resulted in the greatest binding of the organophosphorus compounds).  



   TABLE 1
 Protection of AChE from Agent Inhibition by Various Proteins a
 b
 % AChE Protection
Protein Amount   (Ls)    DFpC GBc VX   GO   
 R R E R E E
AChE (eel) 0.1 77 48 - 55 
 1 100 62 100 78 100 100
 10 100 - 100 - -    Sutyrylcholin-    1 26 - 52 - 100 100
 esterase 10 27 22 100 100 100 100
 (horse) 100 89 61 100 100
Human serum    1    45 34 2 8 (98) (96)
 albumin 10 39 37 7 7 3 11
 100 80 41 5 12 20 17
Bovine serum 1 41 30 (96) 10 (98) 7
 albumin 10 39 37 6 14 9 5
 100 69 43 10 11 15 18
Chymopapain 1 3 3 (98) 17 - 
 (papaya) 10 - 9 (83) 20 - 
 100 56 10 (86) 20 (93)
Subtilisin   8PH 1    - - (95) - 1 (93)
   (3.      amvlolicue-    10 - - (98) - 2 (94)
 faciens) 100 - - (95) - 1 6
Aldolase 1 39 (91) - - 
 (rabbit) 10 56 - (91) - - 
 

   100 84 - - - 9 a Either the radiometric (R) or Ellman's   (E)    assay was used, utilizing from 0.1 to 0:2 U or
 eel AChE in a reaction volume of 1-3 ml.



  The increase (decrease) in AChE activity in the presence of agent where agent is at a
 concentration which causes = 50% AChE inhibition in controls containing no protection
 candidate. The values reported are averages from 2 to 4 determinations with each protein
 at each concentration.



     DFP:    Phosphorofluoridic and bis (l-methyl ethyl) ester
 GB:   Methylphosphonofluoridic    and l-methylethyl ester
 VX: Methylphosphonothioic acid S-[2-[bis(1-methylethyl)amino] ethyl]
 o-ethyl ester
 GD:   Methylphosphonofluoridic    acid 1,2,2-trimethylpropyl ester  
Example V Use of Synthetic Peptides as Binding
 Receptors
 Synthetic peptides able to bind   te    a wide range of alkylating agents can be made by procedures well known in the art. Synthetic peptides modelled after the active sites of the binding receptors of Example
I can also be used as binding receptors. For example, a commercially-available solid-state peptide synthesis procedure is employed. In this procedure, a 4-methylbenzhydrylamine resin is reacted with amino acids using   carbodiimide    coupling.

  The resin (2g per run) is reacted with 6g. each of amino acid and carbodiimide per step.



  After synthesis the peptide is deblocked and removed from the support by hydrofluoric acid (HF) treatment and   purified/characterized    by high pressure liquid chromatography (HPLC). For purification, a reversephase 10 micron Vydac TP218 preparative HPLC column (22.5 x 250 mm) is used with 10 minute isocratic elution (0.1% aqueous trifluoroacetic acid) followed by a 20 min. linear gradient of O to 75% acetonitrile in trifluoroacetic acid. Purified peptides are collected as they are eluted from the column and lyophilized. The process generates a series of peptides with primarily hydrophobic, acidic amino acids in a sequence similar to the papain active site sequence of   H2N-Ser-Cys-Gly-Ser-Cys-Trp-Ala-Phe-Ser-COOH.    Table 2 presents the structure of these   papain-like"    synthetics.  



   Table 2 Candidate agent binding pep tides
 modelled after the active site
 of papain.



  Peptide
EMI19.1     


<tb> No <SEP> Substitutions <SEP> Amino <SEP> Acid <SEP>    Seauence    <SEP> 
<tb>  <SEP>    P1    <SEP> Ser <SEP> Trp
<tb>  <SEP> P2 <SEP> Gly-Ser <SEP> Cys <SEP> Trp <SEP> 
<tb>  <SEP> P3 <SEP> Gly-Ser <SEP> Cys <SEP> Trp-Ala
<tb>  <SEP> p4 <SEP> Cys-Gly-Ser <SEP> Cys <SEP> Trp-Ala <SEP> 
<tb>  <SEP>    P5    <SEP> Ser-Cys-Cly-Ser <SEP> Cys <SEP> Trp-Ala
<tb>  <SEP> P6 <SEP> Ser-Cys-Gly-Ser-Cys-Trp-Ala-Fhe <SEP> 
<tb> Substitute <SEP>    Se    <SEP> for <SEP> Cvs
<tb>  <SEP>    p7    <SEP> Gly-Ser <SEP> Ser <SEP> Trp
<tb>  <SEP> P8 <SEP> Gly-Ser <SEP> Ser <SEP> Trp-Ala <SEP> 
<tb>  <SEP> P9 <SEP>    Cys.Cly-Ser <SEP> Ser <SEP> Trp    <SEP> 
<tb>  <SEP> P10 <SEP> Ser-Cys-Gly-Ser <SEP> Ser <SEP> Trp
<tb>  <SEP> P11 <SEP> Ser-Ser-Gly-Ser 

   <SEP> Ser <SEP> Trp <SEP> 
<tb>  <SEP> P12 <SEP>    Ser-Ser-Gly-SertSer <SEP> Trp-Ala    <SEP> 
<tb> Multiple <SEP> Subtitutions <SEP> 
<tb>  <SEP> P13 <SEP> Ser <SEP> Cys <SEP> Trp-Ala-Phe
<tb>  <SEP> P14 <SEP> Ser <SEP> Cys <SEP> Trp-Ala-His
<tb>  <SEP>    P15    <SEP> Ser <SEP> Cys <SEP> Phe-Ala-His
<tb>  <SEP> P16 <SEP> His-Gly-Ser <SEP> Cys <SEP> Trp
<tb>  <SEP> P17 <SEP> His-Cys-Gly-Ser <SEP> Cys <SEP> Trp
<tb>  <SEP> P18 <SEP> His-Ser-Cys-Gly-Ser <SEP> Cys <SEP> Trp
<tb> 
H2N-Ser-Cys-Glv-Ser-Cvs-Trp-Ala-Phe-Ser-COOH
 Active Site Sequence of Papain  
In peptides   P1    to P6, various fragments of the papain active site have been synthesized.

  In peptides P7 to P12, the active cysteine (Cys) is replaced with serine, resulting in peptides which maintain a hydrophobic character and have a second reactive serine that is similar to the active site for AchE. In peptides P13-P18, histidine (His) is added and phenylalanine (Phe) substituted for
Tryptophan (Trp) to vary the hydrophobic character of the peptides. As shown in Table 3, these peptides, in particular P1, 5, 6, 9, 12, 15, 17, are effective in protecting AchE from inhibition.  



   TABLE 3
 Protection of AChE from Agent Inhibition
 by Synthetic Peptides    b   
   %    AChE Protection (Inhibit on)   Attains   
Peptidea Amount( g) GB GD   VX   
   Pacain    Modeled Peptides
   P1    10 11 16 9
 100 90 97 100
 P2 10 4 9 5
 P3 10 12 10 7
 100 53 -
 P4 10 14 5 9
 100 26 - 26
   P5    10 16 14 11
 100 90 100 98
 P6 10 17 14 24
 100 75 100 81
 P8 10 5 (54) 7
 P9 10 11 8 16
 100 75 - 83
 P10 10 1 (55) 4
 P12 10   10    10 12
 100 - 98 
 P13 10 6 6 9
 P14 10 18 8 9
 100 40
 P15   10    17 15 8
 100 70 100 
 P16 10 - (58) 
 P17 10 15 10 14
 100. 73 - 85
 P18 10 1 5 2
 a See Table 2 for structures.

 

   Using the Ellman's AChE protection assay. Data report the. increase
 (decrease) in AChE activity in the presence of agent at an agent
 concentration which causes 50% AChE inhibition in controls.  



  Peptides designed after the AchE active site show both AchE inhibition and protection. This is apparently due to association of the synthetic peptides directly with the ligand material.



  Example VI Preparation of Degradative Receptors
 for the Hydrolysis of Organophosphorous
 Compounds
 The following example describes preparation and degradative capacity of various receptors that can be used in the article of the present invention for the hydrolysis of organophosphorus compounds.



   Hydrolytic enzyme is available from several sources. Batch cultures of E. coli (ATCC #25922) are maintained on Tryptic Soy Broth at   37"C    and the cells in log phase collected by centrifugation, washed with sterile saline, and stored at   -20 C.   



  The protozoan Tetrahymena thermophilia (a gift from
Dr. Wayne Landis, U.S. Army, CRDEC, Aberdeen) is maintained on broth containing   10g    proteose peptone and 3g yeast extract per liter. These cells are harvested by centrifugation at 1000 xg to prevent cell rupture and washed with   0-9t    saline. Squid (Loligo sp.) hepatopancreas and rat liver are obtained fresh. Extractions are carried out in 2-5 volumes of 5mM Tris-HCl (pH 7.2) containing 400 mM
KC1 and 50 mM Nacl (hereinafter Buffer 1). Extracts of rat liver and squid hepatopancreas are briefly homogenized and then centrifuged at 20,000 x g. T.



  thermophila will lyse significantly even during harvesting. E. coli must be pretreated with  ly-sozyme (20-50 ug/ml for 15 minutes) so that sonication will result in quantitative cell destruction and enzyme extraction.



   Extracts are first purified on a Sephadex G-25 column and eluted with 5mM Tris-HC1 containing 400 mM KCl and 50 mM NaCl. The enzyme-containing fraction is then concentrated in volume using an ultrafilter and applied to a DEAE ion exchange column packed with 5   mMTris-HC1,    pH8. Enzyme is eluted from the ion exchange column with a 0-0.3 M
NaC1 gradient in the packing buffer. Amounts of protein are assayed at each step using the Lowry procedure. O.H.   Lowry,    N.J. Rosenbrough, A.L. Farr and R.J. Randall, Journal of Biological Chemistry, 193:265 (1951). Enzyme activity can be determined in a variety of ways, depending on the reaction products to be expected.

  In this example, fluoride ion liberation from substrates such as DFP (Phosphorofluoridic acid bis (1-Methylethyl) ester) is measured using a selective fluoride ion electrode (Orion F Electrode Model 96-09). Hydrolysis of
DFP, GD, and GB occurred with all the above-mentioned enzyme preparations (Table 4).



  The procedures of Example I were used to test the ability of these hydrolytic ligands to protect AchE from attack by the target ligand. Microgram amounts of the hydrolysis enzymes can protect AchE from being inactivated by a variety of organophosphorus compounds (Table 5). AchE is also protected against the phosphonothionate VX (Methylphosphonothioic acid
S-[2-[bis(l-methylethylamino]ethyl]O-ethyl ester).  



  Since these particular hydrolytic receptors should not degrade the   phosphothionate      VX,    they are most   likely    merely binding to VX. The net effect on protecting AchE from the target ligand is, however, similar. This exemplifies the ability of this invention to inactivate toxic ligands by means other than physical degradation or decomposition of the target ligand.  



   TABLE 4
 Summary of Agent Hydrolyzing Enzyme Activities
   umols    Hvdrolvzed min -1g Protein
Enzyme Purification   DF?    GB GD
Source Stae +Mn -Mn   +n    -Mn +Mn -Mn
Squid Extract - 10.8 2.5 2.0 1.7 2.0
 G-25 - 27.8 3.5 0.6 3.6 0.8
 DEAE 181 113 54.3 18.2 25.7 11.6
Rat Liver Extract - 4.6 4.7 1.7 2.8 1.8
 G-25 - 6.0 23.7 2.2 22.2 1.3
 DEAE 10.3 6.6 2.9 2.7 3.1 0.8
E. coli Extract - 2.4 4.1 1.9 15.9 15.4
 G-25 - 3.2 - - - 
 DEAE - 0 - - - 
T.   thereof    Extract - 2.2 5.2   2.6    12.0 11.0
   thila    G-25 - 12.5 6.9 8.6 34.5 33.2
 DEAE -    0 - - - -    a
 Assayed using the fluoride ion specific electrode assay.

  Typically, 0.1
 to 10mg of protein was assayed in Buffer 1 with or   without   
   0.4M MnCl.    Agent concentration was 10 M. The data are averages of 4
 to 6 determinations with each agent and enzyme for each of 3 to 4
 separate extractions.  



   TABLE 5
   Protection    of AChE from Agent Inhibition by
 Agent Hydrolysis Enzymes a
 C    b % Protection   
Presarationb Amount  g) DFP   GB      G3   
Rat Liver
   Extract    22 92 - - 
 G-25 100 94 - - 
 520 - 63 53 0
 2050 - 62 100 100    100 100 95 - - -   
Squid
   Extract    13 - 2 7 13
 20 55 - - -
 130 - 71 56 42
 300 - 100 100   100   
 G-25 50 42 - 
 81 - 61 69 42
   DEAE    50 51 - -    T.    thermophila
 Extract 49 - 18 20 0
 490 - 100 100 62
 G-25 180 (33) 37 0
E. coli
 Extract 420 - (23) 37 0 a
 Using =0.1 to 0.2 U of AChE in the Ellman's Assay    b
See Example V for enzyme preparation.   



   The increase (decrease) in AChE activity in the presence of agent at an
 agent   concent-tion    which causes   -508    AChE inhibition in controls.  



  Example VII Use of Solid Carriers to Protect
 Against Target Ligands
 This example illustrates the ability of several solid matrices to immobilize the binding and degradative receptors and to protect AchE from attack by target substances.



   Membrane films, MPS sheets and vinylpolymer beads were prepared according to the methods described previously. Approximately 10 mg of protein-bound bovine serum albumin membrane, 1   cm2    of Amerace or   2ml    of vinylpolymer beads were soaked in 0.5 ml of neutral buffer and assayed for the ability to protect AchE from a target chemical (see
Example I for details). Bovine serum albumin membranes, MPS sheets and polymer beads, when impregnated with various binding and degradative receptors, protect AchE from inhibition by toxic organophosphorus compounds (Tables 6 and   7).     



   TABLE 6
 Protection of AChE from Agent Inhibition
 by Immobilized Enzymes a   
 b % AChE Protection (Inhibition)
 Preparation Amount Enzyme Against    (Amount per assay) per test   (pig)    DFP   CR    GD   VX    1. 

  BSA Membranes    (lOmg/assay)   
Control membrane 0 15 12 13 10
AChE 13.5 31 - - 
 27 51 
 91 - 100 100 100
 118 - 100 100 100
 240 - 100 100 100
Aldolase 18 17 - - 
 37 13 - - a-Chymotrypsin 29 7 - - 
 60 7 - - -
Rat   Liver    Enzyme,
 G-25 1510 - 29 88 100
 4400 - 100 74 61
 9066 - 100 67 96
Squid Enzyme,
 Crude 810 - 31 42 0
 G-25 710 - 32 23 15
 1185 - 40 86 37
 2120 - ' 56 38 100
E. coli Enzyme,
 G-25 520 - (72) 9 (27)
T.

   thermophila Enzyme,
 Crude 810 - 15 43 46
 G-25 196 - 0 (7) 20
AChE   +    Liver Enzyme 91   +    4400 - 100 100 100
AChE + Squid Enzyme 79   +    1176 - 100 100 100
AChE   +    Liver + Squid
 Enzymes 82   +    3980 + 1219 - 100 100 100  
 TABLE 6 (Continued)
 Protection of AChE from Agent Inhibition
 by Immobilized Enzymes a
 Preparationb Amount Enzyme   %    AChE Protection (Inhibition) (Amount per assay) per test ( g) DFP   GB    GD VX 2.

  Amerace MPS
 (1   cm /assay)   
Control 0 (6.2) (54) (76) (59)
BSA 2700 14 35 19 7.4
AChE 1 0.4
 11 21    - -   
 57 55 75 100 100
 99 92 - -
 393 100 - - -
 440 - 100 100 100 a-Chymotrypsin 1530 (52) - - 
Aldolase 1240 (56) - - 
Rat Liver Enzyme,
   G-25    2010 - 24 38 21
Squid Enzyme,
   G-25    710 - 32 14 6.2
 2410 - 12 57 32
E.

   coli Enzyme,
   G-25    670 - 31 14 (57)
T.   thermophila   
 Enzyme, G-25 200 - 20 9 (56)
AChE + Liver Enzyme 57 + 983d 77 100 100
AChE   +    Squid Enzyme 57 + 2793d 53 100 100  
 TABLE 6 (Continued)
 Protection of AChE from Agent Inhibition
 by Immobilized Enzymes a   
 b % AChE Protection Inhibition)
 Preparation Amount Enzyme Against    (Amount per assay) per test   (pig)    DFP   GB      GD    VX
AChE   +    Liver   +    Squid
 Enzymes 57   +    2844 + 849d 50 100 57 a the
 Using the Ellman's colorimetric assay.



  Preparation and immobilization of enzymes is described in Examples V and
 I-III,   
C
 The increase (decrease) in AChE activity in the presence of agent at an   
 agent concentration which causes   =504    AChE inhibition in controls. A value
 of 100% protection indicates no effect of agent present on AChE activity.



  Since only total amounts of protein actually bound to the MPS support can
 be determined after immobilization, the individual amounts of each protein
 in a co-immobilized mixture were estimated from amounts bound in non
 mixture preparations.  



   TABLE 7
 Activities of Hydrolysis Enzymes Before
 and After Immobilization
 umols Hvdrolvzed min -1g protein    -lb   
 Preparation   GB    GD
 Free   Enzymes    (mg assayed)
 Liver 0-25 (10.3) 22.9 22.1
 Squid G-25 (4.0) 4.9 4.7
 E. coli Extract (2.1) 3.6 15.7
 T. thermophilia   G-25    (0.90) 5.3 15.6
 BSA Membrane (a0   mg) c e   
 Liver (1.5) 6.5 (-72) 5.0 (-77)
 Squid (0.71) 0.8 (-84) 0.9 (-81)
 E. coli (0.52) 0.8 (-78)   0    (-100)
 T. thermophilia (0.20)   0    (-100)   0    (-100)
 2
 Amerace MPS (1 cm )
 Squid (0.71) 2.9 (-42) 1.7 (-64)
 E.

   coli (0.67) 3.8 (+5) 
   T.      therm.ochilia    (0.20)   0    (-100)   0    (-100)
   Reacti-Cel    (2 ml)
 Liver (0.35) 9.3 (-60) 6.3 (-71)
 Squid (0.55) 5.1 (+3) 1.7 (-64)
 E. coli (0.44) 4.7 (+30) 7.8 (-50)
 T. thermophilia (0.43) 7.0 (+32) 4.0 (-75) a For preparation of enzymes, see Example V.



  Using the fluoride ion assay.



   The amount of support assayed.



   The mg of hydrolysis enzyme immobilized onto the indicated amount of
 support and assayed for hydrolysis activity.



  e The percentage increase/decrease in agent hydrolysis activity after    immobilizacion.     



  Example VIII Ability of Immobilized Receptors to
 Degrade Target Materials
 This example illustrates that, although the immobilized enzymes have a decreased absolute specific activity as compared to the free enzyme, their altered reaction kinetics result in more total ligand hydrolysed than the free enzyme preparation.



  Rat liver enzyme was purified and assayed as described previously. The agent (GD)   (10 3M) was    reacted in a 5 ml volume of buffer 1 with 13 mg of free enzyme, and an amount of receptor equivalent to 4, 2, or 0.3 mg enzyme immobilized on serum albumin membranes, Silica-PVC, or Reacti-Gel, respectively.



  Figure 1 shows that hydrolysis of GD approached steady-state after 30 minutes in the free enzyme preparation, but degradation of GD continued to increase beyond this time in the immobilized preparations. Thus, more ligand is inactivated in the immobilized preparations than would be the case if the receptors were not immobilized.



  Example IX Use of Solid Carriers and Immobilized
 Receptors to Detoxify   Organohosphorous   
 Nerve Agents
 This example illustrates the use of solid supports as carrier in an article of the present invention useful for decontamination of toxic organophosphorus compounds. Experimental conditions were the same as those described in Example V.



  Although enzyme activity is higher in the free enzyme preparation, significant retention of binding  and degradative activity was found when AchE and the rat liver hydrolytic enzyme preparations were co-immobilized onto the Amerace polyvinylchloride and BSA membrane supports (Table 8).  



   TABLE 8
 Activities of Liver and Squid Hydrolysis Enzymes Before and After
   Immobilization    Singly and in Various Combinations    umols Hvdrolvzed/min//Droteinb   
 Preparation   CB    GD
 Free   Enzvmes    (mg assayed)
 Liver G-25   (13*2)    24.4 20.5
 Squid G-25 (4.0) 5.3 4.7
 BSA   Membrane      (i0    mg)
 Liver (9.1) 4.5   (-82)e    3.4 (-83)
 Liver (4.4) 7.7 (-69) 7.2 (-65)
 Squid (2.1) 1.0 (-81) 3.9   (.17)   
 Squid (1.2) 2.2 (-59) 3.6 (-23)
 AChE (0.09) 0 0
 AChE (0.09) + Liver (4.4) 7.3 (-70) 7.2 (-65)
 AChE (0.09)   +    Squid (1.2) 2.9 (-45) 2.4 (-49)
 AChE (0.09) + Liver (4.0) f
 + Squid   (1.2)    11.1   (-73)    8.6  

   (-66)
 2
 Amerace MPS (1 cm )
 Liver (4.4) 7.8 (-68) 4.1 (-80)
 Squid (1.2) 2.4 (-55) 1.3 (-72)
 AChE (0.06) 0 0
 AChE (0.06) + Liver (2.0) 12.9 (-48) 12.9 (-37)
 AChE (0.06 + Squid (2.9) 1.6 (-70) 1.0 (-79)
 AChE (0.06) + Liver (1.0)   +   
 Squid (2.9) 2.7 (-91) 1.4 (-95)
 Controls
 10   mi    BSA Membrane   0    0
 1 cm Amerace MPS   0    0 a-e See footnotes, Table 7.



  Percentage activity loss calculated from the sum of the liver and squid
 free enzyme activities.  



  Example X Non-toxicity of Solid Carriers and
 Immobilized Receptor Preparations
 This example illustrates that membrane-based and MPS based dressings containing immobilized acetylcholinesterase (AChE) and rat liver hydrolysis enzyme are non-toxic to laboratory animals. For each preparation, 8 mm (Miltex 33-28 biopsy punch) wounds were made in the shaved, upper right flanks of ten Hartley guinea pigs (250-350g) anesthetized with sodium nebutal, i.p., at 30 mg/kg. The bandage preparations, 1 cm2 backed onto Johnson  & Johnson
Dermicel first aid tape, were securely placed over the wound and allowed to remain on the wound for 30 minutes. After this time, the bandage was removed and the wound covered with a sterile band-aid. This procedure was repeated for 5 weeks, wounding in a new area each week. The animals were kept under routine observation and the wounds were examined daily.

  Blood samples of 1.5 ml from the ocular vein were collected from each animal at weeks 4 and 5 for immunoanalysis of plasma to detect any circulating antibody to the bandage protein components. During the course of our 5 week study, no obvious morphological changes occurred in the animals. The wounds healed normally and the animals gained weight at a normal rate. Aside from any anesthetic problems, there were no signs of distress or shock in   the' animals.    Repeated application of the bandages caused no obvious problems to the test animals. Weekly application of the bandages did not  result in circulating antibodies to the bandage components.

  Plasma (10 uL) samples from each of the 20 animals were reacted against bandage components
BSA (approximately 10 ug), AChE (approximately 110
Units) or liver extract (approximately 400 ug protein) in an Ouchterlony double immunodiffusion apparatus. Positive controls were run on each plate. These were BSA vs anti-BSA and a guinea pig plasma sample vs anti-guinea pig IgG (raised in goat). In all cases, the controls showed distinct, clear precipitin lines while no lines were seen before or after staining between any of the plasma samples and any bandage component.

  Repeated application of the bandages does not lead to an immune response and the immobilized BSA membrane and
Amerace MPS dressings present no toxic or allergic hazard as determined in test animals
Example XI Use of Solid Carriers and Immobilized
 Receptors to Detoxify Organophos
 phorous Compounds and Protect Animals
 In Vivo
 This example illustrates the removal of DFP, malathion and carbaryl (Sevin) from wounds and skin under real time conditions in laboratory animals.



  Guinea pigs (approximately 700 to 800 g) were anesthetized with nebutal (30 mg/Kg), shaved and wounded with an 8 mm skin biopsy punch (see Example
X for details). The wound was filled with either 50 ul of neat DFP, 50 ul of neat malathion, or a 1 to 4 dilution of carbaryl in ethanol (approximately  6.3 mg). In one animal of each series, agent was immediately washed out of the wound (pH 4 water, approximately 10 ml/wash) to act as a 0 time control. In a second animal of each series, the wound was covered with glass to retard any agent evaporation but no bandage was applied. The wound was washed out after 5 minutes. The third and fourth animals in a series received treatment with one of the wound bandages. After 5 minutes, the bandage was removed and the wound washed out.

  All the wash solutions were then assayed for the ability of the solution to inhibit AchE activity (See
Example I for use of the radiometric assay).



   As shown in Table 9, with no bandage, while significant amounts of DFP and malathion are bound to the wound and skin and washed out of the wound as shown by AchE inhibition, the membrane and MPS bandage preparations are able to remove these toxins as shown by the decreased AChE inhibitory activity of the wound wash-outs. Carbaryl, although easily removed from the skin, is very efficiently detoxified by the MPS preparation.



   A more direct assay measuring AchE-inhibitory activity of the wound surface itself, showed a similar strong detoxification using GD, GB and VX as toxic ligand (Table 10).  



   TABLE 9
   INHIBITION    OF AChE
Agent No Bandage Membrane MPS
DFP 45 11 10
Malathion 35 20 17
Carbaryl 92 75 27 * Percent inhibition in wound washings after a 5
 minute application of agent.  



   Table 10    *   
 % AGENT REMAINING AFTER 5 MINUTES
Agent No Bandage Membrane MPS
GD 55 39 21
GB 72 61 39
VX 69 45 40 * Assumed to be bound to the wound and skin.  



  Example XII Stability of the Solid Carriers and
   ImmobilizedrEnzyme    Preparations
 This example demonstrates that BSA and MPSbased membrane preparations are stable for long periods under a variety of environmental conditions.

 

  During a two-week period, only high temperature   (50"C)    caused any decrease in AchE protecting activity in BSA membranes (Figure 3).



   Although immobilized enzyme preparations made with PVC-silica show reduced initial activity when compared with BSA preparations, low pH (pH = 1) will lead to loss of activity in all cases (Figure 4).



  Soil suspensions up to 10% by weight and blood concentrations (up to 40% by volume) have little or.



  no effect on activity (Figures 5 and 6, respectively).



  Equivalents
 Those skilled in the art will recognize or be able to ascertain, using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed in the following claims. 

Claims

1. An article for inactivating a toxic material, characterized in that the article comprises a first receptor which binds the target ligand, a second receptor which degrades the target ligand, and a solid carrier to which both receptors are affixed.

2. An article of Claim 1, wherein the first receptor is a protein or a peptide which selectively binds the target ligand.

3. An article of Claim 2, wherein the second receptor is an enzyme.

4. An article of Claim 2, wherein the first receptor is a synthetic protein.

5. An article of Claim 4, wherein the synthetic peptide has the formula: H2N-Z-Y-Gly-(Ser)2-Trp-X-COOH, where X, Y, and Z are present either alone or in combination, and X is an optional alanine residue; Y is an optional cysteine or serine residue, and Z is an optional serine residue.

6. An article of Claim 4, wherein the synthetic peptide has the formula: H2N-A-B-C-Ser-Cys-E-F-Y-COOH, where A, B, C, E, F and Y are present either alone or in combina tion and A is an optional histidine residue; B is an optional histidine or serine residue; C is an optional glycine residue; E is an optional tryptophan or phenylalanine residue; F is--an optional alanine residue; and Y is an optional histidine or phenylalanine residue.

7. An article of Claim 4, wherein the synthetic peptide is selected from the group consisting of: a. Ser-Cys-Trp; b. Ser-Cys-Gly-Ser-Cys-Trp-Ala; c. Cer-Cys-Gly-Ser-Cys-Trp-Ala-Phe; d. Cys-Gly-Ser-Ser-Trp; e. Ser-Ser-Gly-Ser-Ser-Trp-Ala; f. Ser-Cys-Phe-Ala-His; and g. His-Cys-Gly-Ser-Cys-Trp.

8. An article of Claim 1, wherein the carrier is selected from the group consisting of cloth, gels, films, powders, foams, sheets and mem branes.

9. An article for inactivating a toxic organic material, characterized in that the article comprises a first receptor which specifically binds the material, a second receptor which degrades the material, and a solid carrier to which both receptors are affixed.

10. An article of Claim 9, wherein the first receptor is a protein or a portion thereof, the second receptor is a protein or a portion thereof, and the carrier is selected from the group consisting of proteinaceous membranes, polyvinyl chloride membranes, powders, cloth, gels, foams and beads.

11. An article of Claim 10, wherein the first receptor is a hydrophobic peptide and the second receptor is a hydrolytic enzyme.

12. An article of Claim 11, wherein the first receptor is a serine esterase peptide and the second receptor is an organophosphorus degrading enzyme.

13. An article for inactivating a toxic orgnic compound, characterized in that the article comprises a first receptor which is acetyl cholinesterase, a second receptor which is an organic compound degrading enzyme, and a solid carrier to which these receptors are affixed, the carrier being selected from the group consisting of proteinaceous membranes, poly vinyl chloride membranes, cloth, powders, beads, gels and foams.

14. An article of Claim 13, wherein the organic compound is selected from the group consisting of: a. diisopropylfluorophosphate; b. methylphosphonofluoridic acid 1,2,2 trimethylpropyl ester; c. methylphosphonofluoridic acid 1-methyl ethyl ester; d. methylphosphonothioic acid 5-(2 bis (1-methyl) amino(ethyl)O-ethyl ester; e. phosphorothioic acid O,O-diethyl 0-(4 nitrophenyl)ester; and f. l-Naphthalenol methylcarbamate.

15. An article for inactivating an organophosphorus pesticide or a nerve agent, characterized in that the article comprises: a. a carrier comprising a silica-impregnated polyvinylchloride membrane; b. acetylcholinesterase bound to the carrier; and c. an organophosphorus-degrading enzyme bound to the carrier.

16. An article for protecting surfaces from a toxic organophosphorous compound, the compound selected from the group consisting of diisopropyl fluorophosphate, methylphosphonofluoridic acid 1,2,2-trimethyl-propyl ester, methylphos phonothioic acid 5- (2-bis (1-methylethyl) amino(ethyl)O-ethyl ester, and phosphorothioic acid O,O-diethyl )-(4-nitrophenyl)ester, characterized in that the article comprises a carrier of bovine serum albumin immobilized thereon, acetylcholinesterase, and an organo phosphorus-degrading enzyme immobilized to the carrier.

17. In a covering used for application to a wound, the improvement comprising at least two receptors affixed to the covering, the first receptor specifically binding a toxic ligand and the second receptor degrading the toxic ligand.

18. In an article used to cover surfaces to protect the surfaces from a contaminant, the improve ment comprising affixing at least two receptors to the article, a first receptor which selec tively binds the contaminant and a second receptor which enzymatically degrades the contaminant.

19. In a device for covering a surface to decon taminate the surface, the improvement com prising: a. a receptor immobilized onto the covering device; and b. an enzyme immobilized onto the covering device.

20. A method of inactivating a toxic target ligand, comprising contacting the ligand with a first receptor, the first receptor immobilizing the ligand and with a second receptor, the second receptor degrading the immobilized ligand, the first receptor and the second receptor affixed to a solid carrier.

21. A method of Claim 20, wherein the first receptor is a protein or a peptide and the second receptor is a protein or peptide.

22. A method of Claim 21, wherein the first receptor is acetylcholinesterase and the second receptor is a hydrolytic enzyme.

23. A method of Claim 22, wherein the hydrolytic enzyme is an organophosphorus-degrading enzyme.

24. A method of inactivating a toxic organic material, comprising contacting the organic material with a first receptor which im mobilizes the organic material and with a second receptor which degrades the material, the first receptor and the second receptor being affixed to a solid carrier.

25. A method of Claim 24, wherein the first receptor is acetylcholinesterase and the second receptor is a hydrolytic enzyme.

26. A method of Claim 25, wherein the hydrolytic enzyme is an organophosphorus-degrading enzyme.

27. A method of detoxifying an organophosphorus compound, comprising contacting the organo phosphorus compound with a first receptor which bids the organophosphorous compound and with a second receptor which degrades the organophos phorus compound, the first receptor and the second receptor bieng affixed to a solid carrier.

28. A method of Claim 27, wherein the first receptor is acetylcholinesterase, and the second receptor is DFPase.

29. A method specially adapted for making an article for inactivation of a toxic target material, the article comprising a first receptor which binds the toxic target material, a second receptor which degrades the toxic target material and a carrier, the method comprising the steps of: a. affixing the first receptor and the second receptor substances to a solid carrier; and b. forming from the carrier having the first receptor and the second receptor affixed thereto a bandage, a sheet, a cloth, beads, a gel, a foam or a powder.