METHOD FOR ISOLATING RETINAL S-ANTIGEN Russian patent published in 2007 - IPC A61K35/00 

FIELD: chemico-pharmaceutical industry.

SUBSTANCE: the present innovation deals with obtaining the solution of retinal S-antigen to be applied as a marker for predicting ophthalmological diseases. Method for obtaining retinal S-antigen out of cattle retina should be carried out due to reducing, extracting, centrifuging, depositing and applying chromatography, moreover, extraction of retinal S-antigen should be carried out at 4°C in 0.05 M tris-hydrochloric acid buffer solution, pH=7.6, containing 0.04% sodium azide, deposition should be carried out in three stages with saturated ammonium sulfate solution, pH=7.2, the first stage of which should be fulfilled due to saturating the extract with ammonium sulfate solution, pH=7.2, up to 20% by weight, the second stage - up to 50% with subsequent centrifuging the residue and dissolving it, and then again up to 50%-saturation with ammonium sulfate, the residue after centrifuging should be collected and dissolved in minimal quantity of tris-hydrochloric acid buffer solution, pH=7.6, containing 0.04% sodium azide; for isolating S-antigen from the solution obtained one should apply Sephacryl S-200 Superfine, concentration up to desired volume should be carried out according to the content of total protein being 0.3-2.0 mg/ml through membranes at the size of pores being 10 kD, and the procedure of chromatographic purification due to gel filtration technique upon Sephacryl S-200 Superfine should be fulfilled upon a 25x100 column at the rate of 1.2 ml/min in tris-hydrochloric acid buffer solution, pH=7.6. S-antigen-containing fractions should be collected and unites to carry out dialysis against 0.15 M sodium-phosphate buffer solution, pH=7.2. The innovation provides increased S-antigen output, shortens the terms of the procedure mentioned and achieves the desired purity.

EFFECT: higher efficiency.

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