A novel, simple, precise, accurate stability indicating liquid chromato-graphy method was developed for the separation and simultaneous quantification of bictegravir, emtricitabine, tenofovir in bulk drug and pharmaceutical formulations. Separation was achieved on ProntoSILHypersorb ODS C18 column using mobile phase of 0.1 M sodium perchlorate, methanol in the ratio of 65:35 (v/v), pH 4.8 at a flow rate of 1.0 mL/min and UV detection was monitored at a wavelength of 258 nm. In these conditions, well resolved peaks were observed with acceptable system suitability at a retention time of 4.6 min for bictegravir, 7.0 min for emtricitabine and 10.1 min for tenofovir. Very high correlated linearity range was found to be 5-30 μg/mL for bictegravir, 20-120 μg/mL for emtricitabine and 2.5-15 μg/mL for tenofovir. The method can separate and identify the unknown degradation compounds formed during stress degradation study.
Brucine (2,3-dimethoxystrychnidin-lO-one) under acidic conditions has been reported to be an effective reagent for the spectrophotometric determination of NO3-, NO2-and Ce4+. 1.2 Subsequent investigations have shown that in combination with potassium persulphate, it can also be used for the spectrophotometric determination of halides3 and c y ~t e i n e . ~ Potassium persulphate was found to be a specific reagent for cysteine, as other thiols tested and amino acids (thioglycollic acid, S-methylcysteine, N-acetylcysteine, cystine, homocystine and glutathione) did not interfere. However, the stability of the blue species formed and the precision and accuracy of this method was not good.Sodium metaperiodate (104-) is an efficient oxidant for converting methyl-substituted o-dihydric phenols into o-qui-nones5 and is also a colour stabiliser.6 This investigation was concerned with the development of a spectrophotometric method for the routine determination of thiols and biologically active amino acids (thioglycollic acid, P-mercaptoethanol, P-mercaptopropionic acid, thiosalicylic acid, cystamine hydrochloride, 2-aminothiophenol, 4-aminothiophenol, cysteine , cystine , tryptophan, glutathione and penicillamine) using brucine -104-. The purple colour (hmax, 500-510 nm) developed was stable for 10 h and hence was suitable for routine work with good precision and accuracy.
Experimental ApparatusAbsorbance measurements were carried out with a Systronics Model 105 (MKl) spectrophotometer using 1-cm glass cells.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.