Title of Invention	"A SYNERGISTIC STORAGE STABLE COMPOSITION "
Abstract	Composition containing a stabilized enzyme or enzyme conjugate.composition containing an enzyme/enzyme conjugate and having long shelf life.composition which stabilizes an enzyme or enzyme conjugate and enhances the ligand-binder reaction.method for preparing a storage stable composition containing an enzyme or enzyme conjugate,

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FIELD OF THE INVENTION The present invention relates to a novel storage stable composition containing an enzyme or enzyme conjugate for use in immunoassays. The invention also provides a method for stabilization of enzymes or enzyme conjugate. BACKGROUND AND PRIOR ART REFERENCES Recently in the field of diagnostic research and clinical examination, measurement of various substances utilizing an immunological reaction and/or an enzyme reaction is widely performed. « Enzymes are used in several biological and immuno-assays. A very popular use of the enzymes is in immuno-assays, wherein, enzymes are used as a labeling substance. However, one major problem associated with enzymes is their stability. Enzymes, as we know are essentially proteins and made up of peptide bonds. Attempts are made to extend the life of enzymes by adopting different methods of storage such as frozen, lyophilized or refrigerated compositions. However, upon thawing, the frozen proteins tend to form aggregates. As a result of this freeze-thaw process, the enzymatic activity of the enzyme is highly diminished. Each enzyme is pH specific and denatures at specific temperature. Enzymes are very sensitive to changes in temperature and sometimes susceptible to degradation even at room temperature. Given these problems with enzymes it is very important to preserve them in their original state for as long a period as possible in order to achieve stable reagents. A very typical example of an enzyme is peroxidase. Peroxidase is an enzyme that catalyzes the oxidation of a number of aromatic phenols and amines, serves as a hydrogen donor and is used as chromogenic, fluorogenic, and chemiluminogenic substrate utilizing hydrogen peroxide as hydrogen acceptor. Peroxidase is now more and more widely used as an enzyme marker for immunoassays and is used to detect sample immunoreactants by measuring the amount of enzyme product. However, peroxidase has poor stability, when stored for a long time, especially in the form of a liquid composition in dilute solution commonly used for assay. The prior art is replete with examples of attempts to stabilize enzymes/enzyme conjugate and prepare storage stable enzyme/enzyme conjugate compositions. WO 86/05207, teaches stabilization of horse radish peroxidase (HRP) conjugate in solution, by using a specific substrate of HRP i.e. tetramethylbenizidine. EP 0 340 068, teaches para amino-salicylic acid, a substrate of HRP has been used for the stabilization of enzymatic activity of horse radish peroxidase in solution. US 005460944, describes aspartate salt has been used for stabilizing enzymatic activity of horse radish peroxidase conjugate in solution. US 5516672, teaches substituted benzene ring having at least one hydroxyl group and at least one substituting group selected from the group consisting of group with a hammett sigma values a P of not more than -0.20 group, with a hammett sigma value o P of not less than +0.24 and amide group has been used as stabilizer for stabilizing the activity of peroxidase or the antibody in solution. US 005512448, describes polyethylene oxide or polyvinyl alcohol has been used for the stabilization of enzymatic activity of horse radish peroxidase in solution. US 005686253, describes an antibody of horse radish peroxidase has been used for the stabilization of enzymatic activity of HRP in solution. Each of the above attempts in the prior art are directed towards the common objective of stabilizing enzymes. However, the approach adopted and taught by each of the above patents is distinct and different. In countries like India, where, irregular supply of electricity adversely affects the stability of reagents and hence, it is important to develop reagents capable of being stored even under difficult conditions for a very long period of time. To fulfil this objective, the applicant has conducted a detailed study and developed a storage stable enzyme/enzyme conjugate composition containing an enzyme/enzyme conjugate and a method for stabilization of enzymes. OBJECTS OF THE INVENTION The main object of the present invention is to provide a composition containing a stabilized enzyme or enzyme conjugate. Another object is to provide a storage stable ^composition containing an enzyme/enzyme conjugate and having long shelf life. Yet another object of the invention is to provide a^eomposition which stabilizes an enzyme or enzyme conjugate and enhances the ligand-binder reaction. Still another object is to provide a^hethod for preparing a storage stable composition containing an enzyme or enzyme conjugate, SUMMARY OF THE INVENTION Accordingly, the invention provides a storage stable composition containing an enzyme or enzyme conjugate and a method for preparing such a composition. DETAILED DESCRIPTION OF THE INVENTION Accordingly, the invention provides a storage stable composition containing an enzyme, or enzyme conjugate, for use in immunoassays said composition comprising: a) a stabilizing amount of a combination of reducing and non-reducing sugars, b) melatonin, c) an enzyme or enzyme conjugate, and d) a buffer system. The focus of the invention is to provide a storage stable composition containing an enzyme or enzyme conjugate having at least the following properties : a) long shelf life; b) capable of maintaining its true state and retaining its properties even in adverse conditions; and c) capable of enhancing immuno/ligand-binder  reaction at stabilizing concentration e.g. antigen-antibody reaction. To prepare a stable composition having the above properties, the applicant has developed a novel method which is described and illustrated hereinbelow. A stable composition according to the invention, is one wherein the enzyme/enzyme conjugate essentially retains its physical, chemical and/or biological stability upon storage. In other words, the composition of the invention is such that it is capable of withstanding repeated freeze/thaw cycles without significant aggregation of the peptide enzyme/enzyme conjugate molecules. "Freeze-thaw cycles" refer to known techniques for using samples from frozen storage, wherein the temperature of the sample is raised to a level which will restore its aqueous state for a sufficient period of time to permit use of the sample, followed by freezing to a temperature, below 0°C and return to frozen storage, preferably at a temperature of -20°C or lower. The aim and intention of this invention is to prepare and provide a composition having ingredients that exhibit synergistic properties, on account of which, the enzyme/enzyme conjugate remains stable for an extended period. It is applicant"s finding that an enzyme or enzyme conjugate when contacted with a combination of reducing and non-reducing sugars along with melatonin and appropriate buffer system stabilizes the enzyme/enzyme conjugate. The resultant composition is stable at temperatures lower than room temperature, at room temperature of 27° to 30°C and even at temperatures upto 40°C. The applicants have found to their surprise that the resultant composition does not lose its activity at least for a period of two years. As said earlier, the composition must contain a combination of reducing and non-reducing sugars. The combination of reducing sugars is taken such that it contains at least one member containing a keto group and another having aldehyde group. This combination of reducing sugars must be present in equimolar concentration. A reducing sugar is one which contains a hemiacetal group that can reduce metal ions or react covalently with amino groups in proteins. Examples of reducing sugars are fructose, mannose, arabinose, xylose, ribose, maltose, lactose, galactose and glucose. All other sugars that do not possess the properties of the reducing sugars are termed as "non-reducing sugars". Examples of such sugars include sucrose, trehalose, sorbose, and raffinose, etc. Any of sugars may be used, the only condition being that the combination used should essentially comprise a reducing and non-reducing sugar such as glucose and fructose and sucrose. Sugars prevent oxidative degradation, strengthen the hydrophobic bonds and prevent denaturation of enzymes/enzyme conjugate. Invert sugar being a equimolar mixture of glucose and fructose acts as antioxidant, preventing the enzyme/enzyme conjugate from oxidation (as oxygen scavengers) and are preferentially oxidized. Sucrose being an example of a non- reducing polyhydric sugar strengthens the hydrophobic bond and such sugars are believed to have a positive effect on hydration of enzyme/enzyme conjugate. Another important aspect is that the combination of reducing sugars comprise an equimolar concentration. Equimolar denotes concentration of the ingredients taken in equal amount in terms of molarity. More specifically, the sugar combination must be present in an isotonic strength i.e. equal to 0.52 freezing point depression of 0.9% NaCl solution. By "isotonic", it is meant that the composition has essentially the same osmotic pressure as human blood. Sugars generally act as cryothermostabilizers and reducing sugars are effective antioxidants. Melatonin is a hormone secreted by the pineal gland. It is a strong antioxidant and prevents the oxidation of enzyme/enzyme conjugate or any other proteins at higher temperature. Melatonin is sparingly soluble in water. It may be dissolved in any solvent that does not affect the enzyme/protein of interest. For example, ethylene glycol and dimethyl sulphoxide (DMSO) etc. The amount of melatonin that may be used in the composition depends on various factors. The recommended amount is 20 - 500 ug/ml. The applicants have also found that existence of an appropriate buffer system adds to the stability of the composition. This buffer system should comprise an alkaline component and ammonium sulfate. The alkaline component i.e. conjugate base or salt of an acid selected from acetate buffer, barbital buffer, borate buffer, citrate buffer, cocodylate buffer, phosphate buffer, tris buffer and the like. It is to be ensured that the alkaline component selected do not affect enzyme/molecule of interest. The amount of the alkaline component may be about 25 to 100 mM. This alkaline component is combined with ammonium sulfate because it is a protein precipitant and is capable of replacing the essential structural water molecule hydrogen bonded to an enzyme/ enzyme conjugate i.e. initiating a salting out reaction, thereby maintaining the molecular structure of the enzyme and preventing its denaturation. Therefore, ammonium sulphate is also an important ingredient in the stabilizing composition. It also enhances the immuno ligand binder reaction. A ligand is a substance which reversibly and non-covalently binds to the binder in the binding assay. A labelled ligand used to pursue the course and conclusion of ligand - binder reaction in the binding assay is known as tracer. A marker atom (offen a radio nuclei) or molecule (e.g. enzyme, fluorescent substance, etc.) linked covalently to ligand to produce the tracer is known as label/conjugate. A chemical moiety that specifically, reversibly and non-covalently binds a ligand in a binding assay is known as binder (e.g. antibody, receptor, carrier proteins etc.). The amount of ammonium sulfate may be present in the solution is up to 25% w/v. Suitable pH ranges for preparation of storage stable composition is about 4 to 9; preferably in the range of about 6 to 8 depending upon the enzyme sought to stabilized. If the composition is intended for pharmaceutical use, the most preferred pH is the physiologically acceptable range i.e. about neutral. Thus, in addition to the sugars and ammonium sulfate, the stabilized composition of the invention may optionally contain a compatible buffer system to maintain the acceptable pH levels. For instance, if the enzyme in question is alkaline phosphatase, alkaline pH should be maintained i.e. from 7.5 to 8.5. According to the principle of present invention, by combining 50 mM of tris-hydroxymethyl aminomethane or 50-200 mM sodium acetate with ammonium sulfate up to 25% w/v the desired pH is achieved. This buffer system is appropriate for this enzyme. However, in case of horse-radish peroxidase, acidic to mild alkaline pH of 4 to 7.5 is required, for which a buffer system working in this pH range is used. Thus, the novelty of the present invention resides in the finding that a sugar or combination of reducing and non-reducing sugars taken at isotonic strength along with melatonin and ammonium sulfate when contacted with an enzyme/enzyme conjugate in 25-100 mM of sodium acetate greatly stabilizes their activity and this resultant composition is capable of being stored for a long period at low or room temperature or even at higher temperatures upto 40°C. The true state and activity of the enzyme or enzyme conjugate are preserved by this combination. It is the applicants finding that the ingredients of the composition exhibit synergistic effect which is unexpected and surprising. The applicants have found that the enzyme/enzyme conjugate remains stable and active for extended periods, say upto about 2 years on account of the synergistic effect exhibited by the ingredients of the composition. Further, the applicants have noticed to their surprise that the enzyme/enzyme conjugate does not lose its activity even when stored at room temperature such as 20 to 35°C or at elevated temperatures upto 40°C. The composition containing the enzyme/enzyme conjugate, the reducing and non-reducing sugars along with melatonin and appropriate buffer system stabilizes the enzyme/enzyme conjugate, helps to retain its activity for extended periods and thus remain stable. The sugars such as non-reducing sugars strengthen the hydrophobic bond and these sugars are believed to exhibit a positive effect on hydration of the enzyme/enzyme conjugate. The sugars also act as cryothermostabilizers and effective antioxidants. Melatonin being a strong antioxidant prevents oxidation of the enzyme/enzyme conjugate at higher temperature. The buffer system retains molecular structure of the enzyme/enzyme conjugate and thus prevents its denaturation even at elevated temperatures. Thus, all the ingredients of the composition exhibit synergistic effect, which effect is surprising and unexpected. Several known enzymes may be stabilized employing the principles of the invention, for example penicillinase, horseradish peroxidase, alkaline phosphatase, 0 galactosidase, glucose-6-phosphate dehydrogenase and malate dehydrogenase. Other known proteins and enzymes may also be stabilized and suitable preparations may be prepared using the principles of this invention. The composition so prepared may be stored in liquid form or lyophilized form. Since, the composition contains ingredients that exhibit synergistic effect, there is no need to add other reducing agents, excipients, buffers or preservatives. However, in order to prepare pharmaceutical compositions, excipients or reducing agents etc. may be added. Excipients can also be added to the liquid medium to further optimize the formulation. For example, cyclodextrin or other carbohydrates can be added to the enzyme/enzyme conjugate to inhibit the rate of intermolecular aggregation during storage in liquid medium. Specific examples of such pharmaceutically acceptable excipients could include mannitol, trimethamine salts ("Tris buffer"), gelatin, human serum albumin or other polypeptides, various small peptides such as glycylglycine, and the like. Other optional components include, but are not limited to, casein, albumin, gelatin or other proteins. Protease inhibitors such as phenyl methyl sulfonyl fluoride, leupeptin, pepstatin may also be included. Preservatives such as amphotericin B, cycloheximide, chloramphenicol, bacitracin, gentamycin, chloroheximide, sodium azide, trimethoprim, sulphomethaxozole may also be included. Additionally, reducing agents such as glutathione may be added. Such ingredients may optionally be added and lyophilized compositions may be prepared. At the time of addition of such ingredients, case should be taken to ensure that they do not interfere or affect the efficacy of the enzymes/enzyme conjugate. It may also be desirable to sterilize the enzyme/enzyme conjugate composition after formulation. Additionally, the improved, storage-stable, composition may optionally include one or more non-ionic detergents, such as TWEEN 80 (Polyoxyethylene sorbitan), TWEEN 20, TRITON-X-100, and the like, in amount of from 0.001 to about 1%, to enhance the stability. Moreover, other pharmaceutically acceptable excipients, well known to those skilled in the art, may also form a part of such compositions. These may include, for example, various bulking agents, additional buffering agents, chelating agents, antioxidants, preservatives, cosolvents, and the like. In another aspect of the invention, the composition thus prepared can be provided as a component of a kit. "Kit" as used herein would mean and include the composition and associated materials like diluents, buffers, excipients, reducing agents etc. required to perform an assay. The kit is often referred to as "reagent pack". The kits are packaged to insure long shelf-life, for instance, in containers. The stabilized composition prepared according to the invention is found to be stable at elevated or low temperatures and withstand repeated freeze/thaw cycles without significant aggregation of the peptide molecules. The stabilized composition or the reagent prepared according to the process of the invention is packed in a appropriate containers, marked with instructions and sealed. At the time of use, the seal can be broken and the contents reconstituted if required and used as per requirement. It can be stored thus for more than 2 years. Because, the composition is stable, this container can be stored at room temperature without any fear of degradation or loss of activity of the enzymes/enzyme conjugate . The contents may be used from time to time. Unlike conventional compositions, repeated use or even leaving the container open for long periods, does not affect the activity of the enzyme/enzyme conjugate at the time of use. In another aspect, the invention also provides a method for stabilization of enzymes/enzyme conjugate , wherein the process comprises the steps of contacting a stabilizing amount of a sugar or combination of sugars (reducing and non-reducing) along with melatonin in the presence of a buffer system, with an enzyme/enzyme conjugate. The resultant composition is a stabilized one, having a shelf life of about 2 years or more. The invention is further illustrated by the following examples which are provided for illustration only and should not be construed as limitations on the inventive concept embodied herein. EXAMPLES Example 1 Carrying out of an immunological determination process. The test was carried out according to the ELISA test principle as a competitive inhibition by means of solid phase bound cortisol primary antibody. 25 ul of sample and 100 ul of cortisol-HRP conjugate working solution were introduced into a polystyrene microwell coated with cortisol primary antibody. Composition of peroxidase storage solution Coritsol - HRP conjugate working dilution buffer. 25mM sodium acetate solution wherein required pH 7.0 achieved by adding 10% ammonium sulfate (w/v), combination of sugar or sugars (reducing and non-reducing) in an isotonic strength i.e. equal  to 0.52 freezing point depression of 0.9% NaCl solution along with melatonin, 0.3% bovine serum albumin and 0.1% thimerosal. Incubation was carried out for 2 hour at 37°C followed by washing five to six time with running tap water, where after 100 ul of substrate solution were added thereto. Substrate solution: 0.003% hydrogen peroxide 100 ug/ml 1MB In lOOmM citrate - acetate buffer pH 3.5. After incubation for 20 minutes at 37°C, the reaction was stopped by adding 50 |al of 4 M H2SO4. The color formed was determined at 450 nM in Tecan spectra ELISA reader. Example 2 Desirable length of Reagent stability (Chan,D.W. (1992). Immunoassay automation. A practical guide, Academic Press, San Diego, CA) Table Removed It is imperative that reagent to have adequate shelf life. A long shelf life is desirable so that a single lot of reagent can be used for long period of time, preferably longer than one year. This will minimize the reagent lot check in process which could be time consuming and expensive. The example 2 shows that the observed length of stability of opened reagent is more than twelve months as compared to three months of desired stability at 4-8°C. This may be because of unique combination of the properties (additive effect) of ammonium sulfate and a sugar or combination of sugars (reducing and non-reducing)along with melatonin in 25-100 mM of sodium acetate. Example 3 Influence of Sucrose (Non-reducing sugar) The above example demonstrate that the working dilution of conjugate is stable only for three to four weeks at 4-8°C in 10 mM phosphate buffer (PB) or 25 mM acetate citrate buffer (ACB) containing isotonic concentration of sucrose. This may be because of inhibitory and chelating effect of phosphate and citrate respectively on peroxidase at 4-8 °C. Example 4 Influence of reducing and non-reducing sugar The example 4 demonstrate that the reducing sugars along with non-reducing sugar in isotonic strength in 10 mM PB or 25 mM ACB is able to stabilize working dilution of enzyme/enzyme conjugate in aqueous solution for 6 to 8 weeks at 4-8°C. This shows the additive effect of reducing and non-reducing sugars for stabilizing the working dilution of enzyme/enzyme conjugate in aqueous solution. Here non-reducing sugars are able to neutralize some effect of phosphate and citrate on peroxidase at 4-8°C. Example 5 Influence of Ammonium sulfate The above example demonstrate that addition often per cent of ammonium sulfate to the lOmM PB or 25 mM ACB containing isotonic strength of reducing and non-reducing sugars able to stabilize working dilution of enzyme conjugate in aqueous solution for more than one year at 4-8°C. This may be because of unique combination of the properties (additive effect) of ammonium sulfate and reducing and non-reducing sugars for stabilizing the working dilution of enzyme/enzyme conjugate in aqueous solution. This combination though retains enzyme/enzyme conjugate activity at 4-8°C but unable to retain at higher temperature (37°C) and above. This may be because of activation of inhibitory and chelating property of phosphate and citrate respectively on peroxidase at higher temperature. Example 6 pH optimization of sodium acetate and dibasic sodium phosphate by ammonium sulfate and their effect on enzyme/enzyme conjugate at higher temperature. The above example demonstrate that an enzyme peroxidase or its conjugate retains the enzymatic activity at higher temperature in sodium acetate solution rather than dibasic sodium phosphate solution wherein the required pH is adjusted with ammonium sulfate. The novelty of present inventions resides in the finding that, when a required pH of sodium acetate is adjusted with ammonium sulfate, a sugar or combination of sugars (reducing or non-reducing) in isotonic strength i.e. equal to 0.52 to freezing point depression of 0.9% NaCl solution, is capable of retaining enzyme activity at higher temperature (37°C.). Further, addition of 20-500 ug/ml of melatonin in above sodium acetate solution, prevent the loss of enzymes/enzyme conjugate activity for longer period (more than three months) at higher temperature (37°C.)and above. Example 7 Influence of ammonium sulfate on Immunological reaction Above example demonstrates that the step wise addition of ammonium sulfate to 10 mM dibasic sodium phosphate or 25 mM sodium acetate containing isotonic strength of a sugar or combination of sugars (reducing and non-reducing) along with melatonin enhances the immuno/ligand binding reaction of enzyme conjugate and almost doubles at the concentration of seven percent. This shows that by using ammonium sulfate in assay buffer the quantity of immunoreagent required for assay reduces to almost half which in turn reduces the cost of the assay. WE CLAIM 1. A storage stable composition useful in immunoassays, said composition comprising: a) a stabilizing amount of a combination of reducing and non-reducing sugars, b) melatonin, c) an enzyme or enzyme conjugate, and d) a buffer system. 2. A composition as claimed in claim 1 wherein the enzyme is selected from the group comprising penicillinase, horseradish peroxidase, alkaline phosphatase, 3   galactosidase,   glucose-6-phosphate   dehydrogenase   and   malate dehydrogenase. 3. A composition as claimed in claim 1 wherein the binding reagent is selected from antigen, antibody, avidin, biotin or protein A, G, L, receptor and carrier protein. 4. A composition as claimed in claim 1 wherein the reducing sugars are present in equimolar concentration/amount. 5. A composition as claimed in claim 1 wherein the reducing sugars are selected from glucose, mannose, fructose, arabinose, xylose, ribose maltose, lactose and galactose. 6. A composition as claimed in claim 1 wherein the non-reducing sugars are selected from sucrose, trehalose, sorbose and raffinose. 7. A composition as claimed in claim 1 wherein the sugar or combination of sugars (reducing and non-reducing) are present in isotonic strength i.e. equal to 0.52 freezing point depression of 0.9% NaCl solution. 8. A composition as claimed in claim 1 wherein melatonin is obtained from natural or synthetic sources. 9. A composition as claimed in claim 1 wherein melatonin is dissolved in suitable solvents like ethylene glycol or dimethyl sulphoxide. 10. A composition as claimed in claim 1 wherein the amount of melatonin is 20 to 500|ig/ml. 11. A composition as claimed in claim 1 wherein the buffer system comprises an alkaline component and ammonium sulphate. 12. A composition as claimed in claim 11 wherein the alkaline component is a conjugate base or salt of an acid. 13. A composition as claimed in claim 11 wherein is selected from any buffer such as acetate buffer, barbital buffer, borate buffer, citrate buffer, cocodylate buffer, phosphate buffer, tris buffer and the like. 14. A composition as claimed in claim 11 wherein amount of the alkaline component of the buffer system is 25 to 100 mM. 15. A composition as claimed in claim 1 wherein if the alkaline component is sodium acetate, it is present up to 100 mM in the solution. 16. A composition as claimed in claim 1 wherein the amount of ammonium sulfate in the buffer system is 25% w/v. 17. A kit for performing assays, comprising the composition as claimed in claim 1 to 16. 18. A kit as claimed in claim 17, further comprising excipients, preservatives, chelating agents, antioxidants such as herein described. 19. A process for preparing a stabilized composition, said process comprising the steps of contacting an enzyme or enzyme conjugate with a combination of a stabilizing amount of a sugar or combination of reducing and non-reducing sugars, melatonin and suitable buffer system. 20. A process as claimed in claim 19 wherein enzyme is selected from the group of  enzymes  such  as  penicillinase,  horseradish  peroxidase,  alkaline phosphatase, (3 galactosidase, glucose-6-phosphate dehydrogenase and malate dehydrogenase. 21. A process as claimed in claim 19 wherein the binding reagent is selected from antigen, antibody, avidin, biotin or protein A, G, L, receptors, carrier protein etc. 22. A process as claimed in claim 19 wherein the reducing sugars are selected from glucose, mannose, fructose, arabinose, xylose, ribose, maltose, lactose and galactose. 23. A process as claimed in claim 19 wherein the non-reducing sugars are selected from sucrose, trehalose, sorbose, and raffinose. 24. A process as claimed in claim 19 wherein reducing and non-reducing sugars are present in isotonic strength i.e. equal to 0.52 freezing point depression of 0.9% NaCl solution. 25. A composition as claimed in claim 19 wherein the buffer system comprises an alkaline component and ammonium sulphate. 26. A composition as claimed in claim 19 wherein the alkaline component i.e. conjugate base or salt of an acid. 27. A composition as claimed in claim 19 wherein the alkaline component is selected from any alkaline buffers such as acetate, barbital buffer, borate buffer, citrate buffer, cocodylate buffer, phosphate buffer, tris buffer and the like. 28. A composition as claimed in claim 19 wherein the amount of the alkaline component of the buffer system is 25 to 100 mM. 29. A process as claimed in claim 19 wherein if alkaline component it is sodium acetate and is present up to 100 mM in solution. 30. A process as claimed in claim 19 wherein an amount of ammonium sulfate is present upto 25% w/v in the solution. 31. A stabilized composition containing an enzyme or enzyme conjugate substantially as herein described and illustrated. 32. A process for preparing a stabilized enzyme/enzyme conjugate composition substantially as herein described and illustrated. 33. A kit substantially as herein described and illustrated.

Documents:

1190-DEL-2000-Abstract-(25-04-2008).pdf

1190-DEL-2000-Abstract-31-03-2008.pdf

1190-del-2000-abstract.pdf

1190-DEL-2000-Claims-(25-04-2008).pdf

1190-DEL-2000-Claims-31-03-2008.pdf

1190-del-2000-claims.pdf

1190-DEL-2000-Correspondence-Others-(25-04-2008).pdf

1190-DEL-2000-Correspondence-Others-31-03-2008.pdf

1190-del-2000-correspondence-others.pdf

1190-DEL-2000-Description (Complete)-(25-04-2008).pdf

1190-del-2000-description (complete).pdf

1190-DEL-2000-Description (Complete)31-03-2008.pdf

1190-DEL-2000-Form-1-(25-04-2008).pdf

1190-DEL-2000-Form-1-31-03-2008.pdf

1190-del-2000-form-1.pdf

1190-DEL-2000-Form-13-31-03-2008.pdf

1190-del-2000-form-18.pdf

1190-DEL-2000-Form-2-(25-04-2008).pdf

1190-DEL-2000-Form-2-31-03-2008.pdf

1190-del-2000-form-2.pdf

1190-del-2000-form-26.pdf

1190-DEL-2000-Form-3-31-03-2008.pdf

1190-del-2000-form-3.pdf

1190-del-2000-form-5.pdf

1190-DEL-2000-GPA-31-03-2008.pdf