Size-exclusion chromatography based on silica-diol sorbent was employed to analyze the recombinant proinsulin fusion protein obtained during the process of refolding and the following ion-exchange purification. The assay was qualified as a control method estimating its accuracy, precision, linearity, limit of detection, limits of quantitation, specificity, and robustness. The results show the reliability for the intended use.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
June 2007
One of the main stages of human recombinant insulin (HRI) production is the hormone purification by means of reversed phase high-performance liquid chromatography (RP HPLC). The optimization of this stage determines the increase of the total manufacturing yield. Therefore, the cost of the sorbent used in HPLC influences the cost of the manufacturing product, i.
View Article and Find Full Text PDFThe relationship between the structures of polymyxins and their histamine releasing action on rat mast cells was studied. Analogues of polymyxin B (PB) had different hydrophobic properties, positive charge and peptide chains (deca-, nona- and heptapeptides). The biologic activities of cyclic and decyclic heptapeptides (analogues of PB), and polymyxin M and its decyclic form were investigated.
View Article and Find Full Text PDFPhotoreceptor discs from rod outer segments of cattle retina were treated with (a) papain, (b) thermolysin or (c) trypsin, the procedures resulting in the cleavage of the rhodopsin polypeptide chain between (a) 323 and 324, 236 and 237, 241 and 242, (b) 327 and 328, 240 and 241, or (c) 339 and 340 amino acid residues, respectively. In all the cases, partially digested rhodopsins proved to be competent in generating photoelectric potential and increasing membrane conductance of the discs adsorbed onto phospholipid-impregnated collodion film. The kinetics of generation and dissipation of photopotential as well as of formation of metarhodopsin II and of the light-induced rhodopsin protonation were found to be the same in the partially digested preparations and in the intact one.
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