Title of Invention	"A SYNERGISTIC STABILIZED COMPOSITION USEFUL FOR IMMUNOASSAY"
Abstract	Present invention relates to a storage stable composition comprising an antibody in aqueous solution at optimal dilution. The invention also provides a method for preparation of storage stable-compositions containing an antibody in aqueous solution at optimal dilution.

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FIELD OF THE INVENTION The present invention provides a storage stable composition comprising an antibody in aqueous solution at optimal dilution. The invention also provides a method for preparation of storage stable-compositions containing an antibody in aqueous solution at optimal dilution, BACKGROUND AND PRIOR ART REFERENCES Recently in the field of immuno- diagnosis, measurement of various substances utilizing an immunological reaction is widely performed. Antibodies represent a specific class of proteins generated by the immune system. These protein molecules are capable of binding or complexing with invading molecules, often termed as "antigens". Antibody molecules recognize the antigen by complexing its antigen-binding sites with areas called 'epitopes'. The epitopes fit into the antigen-binding sites of the antibody, thus enabling the antibody to bind to the antigen. Antibodies are used in immuno-assays. In immuno-assays, antibodies are widely employed for detection or determination of substances in biological samples. These assays involve the binding of an antigen with an antibody. Such binding occurs with high specificity even at low concentration. However, one major problem associated with antibodies is their stability. Antibodies are very sensitive and are very susceptible to degradation. At times, antibody-clevage products or antibody-protein compositions form aggregate during frozen storage. As a result of the freeze-thaw process also, heterogenous unstable compositions may result wherein immuno reactivity is highly diminished. Such aggregates of antibody-protein compositions as a result of storage instabilities often require additional purification steps to restore the composition to its homogeneous state. Given these problems with antibodies, it is very important to preserve antibodies in their original state for as long a period as possible. It is also known that the activity of the antibody is reduced when the level of antibody in aqueous solution is low Thus, it is difficult to store the antibody in aqueous solution for long time when the concentration of antibody is low and it is a serious problem for quality control as a reagent used for measurement. Therefore, the stabilization of antibody is strongly recommended. Several attempts have been made, at academic and other levels to study the decomposition of proteins and, in turn of antibodies and thus reduce the inactivation thereof. For example, WO 98/56418, describes a stabilized antibody formulation, wherein the buffer is about 20-30 mM acetate at about pH 5.0, the polyol (sugar) is trehalose in an amount of about 1-15% W/V, the surfactant is polysorbate in an amount of about 0.01-0.03% and wherein the formulation further comprises benzyl alcohol in an amount of about 0.5 to 1%. WO 97/04801 teaches stabilization of an antibody in lyophilized state either using sucrose or trehalose. WO 96/41164 teaches stabilization of antibody by either using sucrose or glucose or mannitol in an amount of 5-25%. Effect of combination of sugar has not been demonstrated. Journal of Immuiiological Methods 181, 37-43: 1995, describes antibody stabilization in lyophilised state by use of trehalose. EP 661060/US 5608038 describes stabilized antibody formulation wherein either 4% glucose/sucrose has been used. Effect of combination of these sugar has not been demonstrated, Each of the above attempts in the prior art are directed towards the common objective of preparing stable antibody compositions, however, the approach adopted and taught by each of them is distinct and different. In countries like India, the irregular supply of electricity adversely affects the stability of reagents, and hence, it is important to develop compositions 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 antibody compositions. OBJECTS OF THE INVENTION It is therefore an object of this invention is to provide a composition useful in immuno-assays and containing an antibody whose activity is stabilized in aqueous medium. Another object of the invention is to provide a storage stable composition, which does not reduce of interfere with immunological reactions of antibody but enhances the immuno-reactivity of antibody at stabilizing concentration. Yet another object is to provide compositions containing antibodies and having a long shelf-life. Still another object is to provide a method for preparing storage stable antibody compositions. SUMMARY OF THE INVENTION Accordingly, the invention provides a storage stable composition containing an antibody in aqueous medium at optimal dilution and a method for preparing such a composition. DETAILED DESCRIPTION OF THE INVENTION Accordingly, the invention provides a storage stable composition containing an antibody in aqueous medium at optimal dilution and suitable for use in immunoassays, said composition comprising: a) stabilizing amount of reducing and non-reducing sugars; b) melatonin; c) an antibody; and d) a buffer system. Thus, the intent of the invention is to provide a composition, which is consistent and homogeneous and contains an antibody in aqueous medium at optimal dilution. The invention aims to provide a storage stable composition containing an antibody having atleast 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-reactivity at stabilizing concentration i.e. antigen-antibody reaction. A stable composition is one wherein the antibody 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 (antibody) 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 antibody remains stable for an extended period. It is applicant's finding that an antibody when contacted with a combination of reducing and non-reducing sugars along with melatonin and appropriate buffer system stabilizes the antibody. The resultant composition is stable at temperatures lower than room temperature of 27° to 30°C and even at elevated 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. 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 such reducing sugars are fructose, manno$e, 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 prevents oxidative degradation, strengthen the hydrophobic bonds and prevents denaturation of an antibody. Invert sugar being a equimolar mixture of glucose and fructose acts as antioxidant, preventing an antibody 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 the antibody. Another important aspect is that the combination of the non-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 i.e. reducing and non-reducing 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 antibody 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 antibody/protein molecule 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 µg/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 may be a conjugate base or salt of an acid and may be selected from acetate buffer, barbital buffer, borate buffer, citrate buffer, cocodylate buffer, phosphate buffer, tris buffer and the like. The amount of the alkaline component may be about 25 to 100 mM. For example, if the alkaline component is sodium acetate, it may be present in an amount of upto 100 mM. This alkaline component is combined with ammonium sulfate because ammonium sulphate is a protein precipitant and is capable of replacing the essential structural water molecule hydrogen bonded to an antibody i.e. initiating a salting out reaction, thereby maintaining the molecular structure of the antibody aind 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 labeled 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 that may be present in the solution is upto 15%. While selecting the alkaline component, it is to be ensured that the alkaline component selected does not affect the antibody/molecule of interest in the composition.. Suitable pH ranges for preparation of storage stable composition is about 5 to 9; although the range of about 6 to 8 would be appropriate. 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. The composition may be maintained in aqueous medium at optimal dilution, meaning thereby that the antibody dilution is maintained in ready to use state. Thus, the novelty of the present invention resides in the finding that an antibody contacted with a sugar or combination of reducing and non-reducing sugars taken at isotonic strength along with melatonin and a buffer system 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 antibody is 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 antibody 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 antibody 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 antibody, the reducing and non-reducing sugars along with melatonin and appropriate buffer system stabilizes the antibody, 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 antibody. The sugars also act as cryothermostabilizers and effective antbxidants. Melatonin being a strong antioxidant prevents oxidation of the antibody at higher temperature. The buffer system retains molecular structure of the antibody 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. The antibody that may be stabilized may be an Immunoglobulin, formed by the immune system of a host in response to exposure to an antigen. As is known, antibodies bind specifically to antigens, hence, within the scope of the invention are envisaged antigen-binding protein molecules. The antibodies for use in the present invention may be monoclonal or polyclonal and can be prepared by techniques known in the art. Antibodies may include an tmrnunoglobulin or fragments thereof. The intention of the invention is to include immunoglobulins of various classes and isotypes such as IgA, IgM, IgD, IgE, IgGl, IgG2a, IgG2b, IgG3, IgG4, etc. Fragments may include Fab, F(ab)2. Generally, the antibody is stabilized at 2-8°C. In further aspect., the invention also provides a process for preparing a stabilized antibody composition, comprising the steps of contacting a stabilizing quantity of reducing and non-reducing sugars along with melatonin with an antibody solution in the presence of an appropriate buffer system. The composition prepared by this process is stable at low temperatures such as -4°C, at room temperature as well as elevated temperatures. This process is preferably effective at 2 - 8°C. Thus, the novelty of the present invention resides in the finding that a sugar or combination of sugars (reducing and non-reducing) at isotonic strength along with melatonin and suitable buffer system when contacted with an antibody greatly stabilizes the antibody, and this resultant composition is capable of being stored for a long period at higher temperature. The novelty of the present invention also resides in the finding that ammonium sulfate in the buffer system not only stabilizes the antibody but also enhances the immuno-reaction. In sum, the ingredients i.e. sugar or combination of sugars (reducing and non-reducing) along with melatonin and suitable buffer system act together and exhibit synergistic effect in combination with an antibody, which effect is surprising and unexpected. It is on account of this synergistic effect that the antibody in the composition is stabilized and the composition has a long life at higher temperature. The composition so prepared may be stored in liquid form or lyophilized form. Since, the composition contains ingredients that exhibit a synergistic effect, there is no need to add other reducing agents, excipients, buffers or preservatives. 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, activity or stability of the antibodies. The composition so prepared may be stored in liquid form or lyophilized form. 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 composition of the invention. For example, cyclodextrin or other carbohydrates can be added to the antibody composition to inhibit the rate of intermolecular aggregation during storage in liquid medium. Specific examples of such pharmaceutically acceptable excipients would include mannitol, trimethamine salts ("Tris buffer"), gelatin, human serum albumin or other polypeptides, various small peptides such as glycylglycine, and the like. 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. 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. As said earlier, 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 antibody. It may also be desirable to sterilize the antibody 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. 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 ensure long shelf-life, for instance, in containers. The stabilized composition prepared according to the invention is found to be stable at low temperature, at room temperature (20 to 35°C) or at elevated temperatures (upto 40°C) and can 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 antibody. 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 antibody at the time of use or reuse. This invention is illustrated in detail by way of the following examples, which should not be read as limitations on the inventive concept embodied herein. EXAMPLES Example 1 Carrying out of an immunological determination process (Table Removed) The test was carried out according to enzyme immunoassay test principle as a competitive inhibition by means of liquid phase assay of cortisol. 25 µl of sample and 100 ul of cortisol antibody working solution and 100 ul of cortisol horse radish peroxidase conjugate is added into 12 x 75 mm glass test tube. Composition of antibody storage solution Coritsol -antibody working dilution buffer. 10 mM sodium acetate solution wherein the required pH 7.0 is adjusted by adding 7.5% ammonium sulfate. A sugar or combination of 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 20-200 ng/ml of melatonin 0.2% gelatin, 0.1% bovine serum albumin and thimerosal. Incubation was carried out for over night at 4°C, followed by addition of 200 µl of 1:40 diluted second antibody and incubated for 2 hour at 37°C, followed by centrifugation and washing of immunoprecipitate 3-4 times with 10mM phosphate buffer saline (PBS). Where after 500µl of substrate solution were added thereto. Substrate solution: 100 µg/ml of tetramethyl benzidine (1MB) 0.003% H202 (Hydrogen Peroxide) in 100 mM Citrate acetate buffer pH 3.5 After incubation for 20 minutes at 37°C, the reaction was stopped by adding 250 µl of 4 M H2S04. 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 chat 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 eighteen months as compared to three months of desired stability at 4°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 10-100 mM sodium acetate. Example 3 Influence of Sucrose (Non-reducing sugar) (Table Removed) The above example demonstrate that the working dilution of antibody is stable for three to four weeks at 4-8°C in 10 mM phosphate buffer (PB) whereas 10 mM of acetate citrate buffer (ACS) able to stabilize up to 10 weeks, containing isotonic concentration of sucrose. This may be because of strong inhibitory and mild chelating effect of phosphate and citrate on antibody at 4-8 °C. Example 4 Influence of reducing and non-reducing sugar (Table Removed) 1.8 5% Sucrose in 2.00% Fructose 2.00% Glucose The example 4 demonstrate that the reducing sugars along with non-reducing sugar in isotonic strength in 10 mM PB is able to stabilize working dilution of antibody in aqueous solution for 12 to 18 weeks at 4-8°C .Whereas 10 mM ACB is able to stablize antibody up to 30 weeks at 4-8°C. This shows the additive effect of reducing and non-reducing sugars for stabilizing the working dilution of antibody in aqueous solution. Example 5 Influence of Ammonium sulfate (Table Removed) The above example demonstrate that addition of 10% of ammonium sulfate to the 10mM PB and lOmM ACB containing isotonic strength of reducing and non-reducing sugars able to stabilize working dilution of antibody 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 antibody in aqueous solution. This combination though retains antibody activity at 4-8°C but unable to retain at higher temperature (37aC) and above. This may be because of activation of inhibitory and chelating property of phosphate and citrate respectively on antibody at higher temperature. Example 6 pH optimization of sodium acetate and dibasic sodium phosphate by ammonium sulfate and their effect on immuno reactivity of antibody at higher temperature. (Table Removed) The above example demonstrate that an antibody retains the immuno reactivity 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 immuno reactivity of an antibody at higher temperature (37°C.). Further, addition of 20-200 µg/ml of melatonin in above sodium acetate solution, prevent the loss of immuno reactivity of an antibody for longer period (more than three months) at higher temperature (37°C.)and above. Example 7 Influence of ammonium sulfate on Immunological reaction (Table Removed) Above example demonstrates that the step wise addition of ammonium sulfate to 10 mM dibasic sodium phosphate or 10 mM sodium acetate containing isotonic strength of reducing and non-reducing sugars enhances the immunological reaction 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 stabilized composition for use in immuno-assays, said composition comprising: a) a stabilizing amount of a combination of reducing and non-reducing sugars, b) melatonin, c) an antibody, and d) a buffer system. 2. A composition as claimed in claim 1 wherein the antibody is selected from the group of immunoglobulins comprising IgA, IgM. IgD, IgE, IgG1, IgG2a, IgG2b, IgG3, IgG4, and fragments such as Fab, and F(ab)2. 3. A composition as claimed in claim 1 wherein the antibody is present in aqueous solution at optimal dilution. 4. A composition as claimed in claim 1 wherein the non-reducing sugars are present in equim01ar amount. 5. A composition as claimed in claim 1 wherein the reducing sugars are selected from the group comprising fructose, mannose, arabinose, xylose, ribose, galactose glucose, maltose and lactose. 6. A composition as claimed in claim 1 wherein the non-reducing sugars are selected from the group comprising sucrose, trehalose, sorbose and raffmose. 7. A composition as claimed in claim 1 wherein the solution is unaffected by contaminants 8. 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. 9. A composition as claimed in claim 1 wherein melatonin is obtained from natural or synthetic sources. 10. A composition as claimed in claim 1 wherein melatonin is dissolved in suitable solvents spch as ethylene glycol or dimethyl sulphoxide. 11. A composition as claimed in claim 1 wherein the amount of melatonin is present in an amount of 20 to 200µg/ml. 12. A composition as claimed in claim 1 wherein the buffer system comprises an alkaline component and ammonium sulphate. 13. A composition as claimed in claim 1 wherein the alkaline component is a conjugate base or salt of an acid. 14. A composition as claimed in claim 1 wherein the alkaline component is selected from the group comprising acetate buffer, barbital buffer, borate buffer, citrate buffer, cocodylate buffer, phosphate buffer, tris buffer and the like. 15. A composition as claimed in claim 1 wherein the amount of the alkaline component in the buffer system is 25 to 100 mM. 16. A composition as claimed in claim 1 wherein if the alkaline component is sodium acetate, it is present up to 100 mM. 17. A composition as claimed in claim 1 wherein the amount of ammonium sulfate in the buffer system is 15% w/v. 18. A composition as claimed in claim 1 wherein the composition is prepared and stored at pH of 5-9. 19. A kit for performing assays comprising a composition as claimed in claim 1 to 18. 20. A kit further comprising buffer system, excipients, preservatives, chelating agents and antioxidants such as herein described. 21. A process for preparing a stabilized composition, said process comprising the steps of contacting an antibody with a combination of a stabilizing amount of sugar or combination of reducing and non-reducing sugars, melatonin and suitable buffer system 22. A process as claimed in claim 21 wherein the antibody is selected from the group of immunoglobulins comprising IgA, IgM. IgD, IgE, IgG1, IgG2a, IgG2b, IgG3, lgG4, and fragments such as Fab, and F(ab)j. 23. A process as claimed in claim 21 wherein the non-reducing sugars are present in equimolar amount. 24. A process as claimed in claim 21 wherein the reducing sugars are selected from the group comprising glucose, mannose, fructose, arabinose, xylose, ribose, maltose, lactose and galactose. 25. A process as claimed in claim 21 wherein the non-reducing sugars are selected from the group comprising sucrose, trehalose, sorbose, and raffinose. 26. A process as claimed in claim 21 wherein the reducing and non-reducing sugars are present in isotonic strength i.e. equal to 0.52 freezing point depression of 0.9% NaCl solution. 27. A process as claimed in claim 21 wherein melatonin is obtained from natural or synthetic sources. 28. A process as claimed in claim 21 wherein melatonin is dissolved in suitable solvents like ethylene glycol or dimethyl sulphoxide. 29. A process as claimed in claim 21 wherein melatonin is present in an amount of 20 to 200µg/ml, 30. A process as claimed in claim 21 wherein the buffer system comprises an alkaline component. 31. A process as claimed in claim 21 wherein the alkaline component, is a conjugate base or salt of an acid. 32. A process as claimed in claim 21 wherein the alkaline component is selected from any buffer such as acetate buffer, barbital buffer, borate buffer, citrate buffer, cocodylate buffer, phosphate buffer, tri buffer and the like. 33. A process as claimed in claim 21 wherein the amount of the alkaline component of the buffer system is 25 to 100 mM. 34. A process as claimed in claim 21 wherein if alkaline component is sodium acetate, it is present up to 100 mM. 35. A process as claimed in claim 21 wherein an amount of ammonium sulfate is present upto 15% w/v. 36. A process as claimed in claim 21 wherein the composition is prepared and stored at a pH in the range of 5-9. 37. A storage stable composition containing an antibody in aqueous solution substantially as herein described and illustrated. 38. A process for preparing a stable antibody composition substantially as herein described and illustrated. 39. A kit substantially as herein described and illustrated.

Documents:

1191-del-2000-abstract.pdf

1191-del-2000-Assignment-(18-04-2011).pdf

1191-del-2000-claims.pdf

1191-del-2000-Correspondence Others-(18-04-2011).pdf

1191-DEL-2000-Correspondence-Others-(25-10-2010).pdf

1191-del-2000-correspondence-others.pdf

1191-del-2000-correspondence-po.pdf

1191-del-2000-description (complete).pdf

1191-del-2000-form-1.pdf

1191-del-2000-form-13.pdf

1191-DEL-2000-Form-15-(20-10-2010).pdf

1191-del-2000-form-19.pdf

1191-del-2000-form-2.pdf

1191-del-2000-form-26.pdf

1191-del-2000-form-3.pdf

1191-del-2000-form-5.pdf