Simultaneous Spectrophotometric Determination of Nifuroxime and Furazolidone in Pharmaceutical Preparations

Abstract

Two spectrophotometric methods have been developed for the simultaneous determination of nifuroxime and furazolidone in their pharmaceutical preparations. No preliminary separation step is required in either method. The first, a modified Vierordt method, gives accurate and reproducible results for both drugs. Mean percent recoveries for nifuroxime and furazolidone were 99.50 ±1.59 and 100.20 ±1.16 (P = 0.05), respectively. This method also gives accurate and reproducible results for the determination of nifuroxime and furazolidone in their pharmaceutical preparations: Tricofuran vaginal suppositories and powder. The second method, which involves the use of the first-derivative curves, gives unreliable results; the reasons for these are discussed.

In vivo multispectral photoacoustic and photothermal flow cytometry with multicolor dyes: A potential for real‐time assessment of circulation, dye‐cell interaction, and blood volume

“…In particular, we can measure the PT signals at 532 nm (or 610 nm, 635 nm, 660 nm, and 690 nm, depending on the selected dye) and 1,064 nm and calculate the total [Hb] at 532 nm and the fraction of HbO 2 at 1,064 nm. An overdetermined Vierordt's equation system (i) at two wavelengths (142–146) is used for dyes and hemoglobin species at a nanomolar level (147): and (ii) an overdetermined Vierordt's system at four wavelengths is used to further decrease the overall error (137, 138): Here A is absorbance acquired from PA measurements in vivo or calculated from PT measurements. As the wavelengths for Vierordt's method, the maxima of functions $\varepsilon_{\rm a}^{\lambda_1} \big/ \varepsilon_{\rm b}^{\lambda_1} \sqrt{\varepsilon_{\rm a}^{\lambda_1} \varepsilon_{\rm b}^{\lambda_1}} = f\;(\lambda)$ and $\varepsilon_{\rm b}^{\lambda_1} \big/ \varepsilon_{\rm a}^{\lambda_1} \sqrt{\varepsilon_{\rm a}^{\lambda_1} \varepsilon_{\rm b}^{\lambda_1}} = f\;(\lambda)$ are used.…”