Assay of biotin in pharmaceuticals utilizing its inhibitory effect on Pd(II) catalyzed ligand substitution reaction

A spectrophotometric approach that is straightforward, efficient, highly sensitive, and precise has been devised for quantifying biotin (BTN) in both its pure state and pharmaceutical samples. Therapeutic assessment and patient bioavailability require biotin analysis in biological and pharmacological samples. Some drug detection methods require sophisticated equipment that many quality control laboratories and universities in developing nations lack. The methodology relies on the inhibitory approach of BTN on the Pd(II) promoted ligand substitution (LS) reaction involving 2,2′ bipyridine (BiPy) and hexacyanoferrate(II). The process entails replacing cyanide in [Fe(CN)₆]^4– with BiPy in ammonium dodecyl sulfate (ADS) micellar medium, triggering the development of a complex [Fe(CN)₄ BiPy]^2-. The complex demonstrates a significant level of absorption at a specific wavelength of 440 nm. The established limit of detection for BTN is 0.089 μg mL⁻¹. Experiments on recovery were conducted to confirm the precision and accuracy of BTN quantification. The suggested approach has been effectively utilized for the examination of BTN in pristine samples and various medications, demonstrating remarkable levels of precision and accuracy. The outcomes showed good agreement when compared to the findings of the official analytical method. The excipients typically employed in medicines do not exhibit any interference with the suggested methodology. This methodology effectively determines trace levels of various drugs and biological molecules that can significantly hinder the catalytic efficiency of Pd(II).

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