Abstract
A new simple and direct electroanalytical method was developed for the determination of azidothymidine in commercial pharmaceutical preparations. It is based on differential pulse voltammetry at silver solid amalgam electrode with polished surface (p-AgSAE) or surface modified by mercury meniscus (m-AgSAE).
The electroreduction of azidothymidine in basic media at these electrodes gives rise to one irreversible cathodic peak. Its potential in 0.05 mol L-1 borate buffer, pH 9.3 at ca. - 1050 mV is comparable to that using hanging mercury drop electrode (HMDE).
Achieved limits of quantitation are in the 10(-7) mol L-1 concentration range for both amalgam electrodes. According to the procedure based on the standard addition technique, the recoveries of known amounts of azidothymidine contained in pharmaceutical preparations available in capsules were 101.4 +/- 1.8% (m-AgSAE), 100.3 +/- 3.5% (p-AgSAE) and 102.0 +/- 1.0% (HMDE) (n = 10).