Label-free masterful spectrofluorimetric systems for minuscule tracking of natural antioxidant vincamine in the pharmaceutical, environmental, and biological samples: Comparative greenness, whiteness, and blueness appraisal

Abstract

In this work, we present two label-free spectrofluorimetric systems for the swift quantification of vincamine (VN) in various matrices without the need for knotty fluorescent dyes, drastic conditions, or expensive instrumentation, which are key merits of the quantifying procedures. The first method (Method I) relied on the direct mix-and-read assay for exploiting the intrinsic fluorescence of VN, adopting λ_ex/em of 272/334 nm using water as a diluting solvent. The method fitted linearity across the concentrations of 1.00 – 10.00 µg mL⁻¹. In the second method (Method II), upon turning off the photoinduced electron transfer (PET) of tertiary amine in the piperidine moiety to the indole scaffold using 0.1 M hydrochloric acid, the fluorescent signal was augmented up to 158 %. This commendable boost in the fluorescent sensitivity allowed the minute detection of VN in spiked human plasma with a standard deviation not exceeding 1.30. Using the acid-blocked PET-based probe, the fluorescent signal was linearly correlated with VN concentration across 0.25 – 6.00 µg mL⁻¹ using λ_ex/em of 277/323 nm. These streamlined procedures proficiently evaluated VN in both the sole and co-formulated capsules without any significant interference from capsule filler material or the co-formulated medication “piracetam”. In addition, the two submitted procedures were successfully executed to check VN through weight variation testing in the Brain-ox® capsules with good acceptance values. The constructed platforms ensemble estimated VN in the environmental samples (tap and river water) with acceptable percentage recoveries and standard deviations (0.95 – 1.65). The procedures' green, white, and blue fitness were appraised through a plethora of computational tools, including GAPI, AGREE, AGREEprep, the RGB 12 algorithm, and BAGI. The evaluation showed that the proposed works effectively strike a compromise between sustainability and functionality postulates. This highlighted that designed approaches are perfectly suited as ecological frameworks for minuscule assaying of VN in crucial pharmaceutical, biological, and environmental samples.