Derivative matrix-isopotential synchronous spectrofluorimetry: a solution for the direct determination of urinary δ-aminolevulinic acid

Abstract

The excitation and emission spectra formulated 3D contours, from which isopotential trajectory was selected for the direct detection of urinary δ-aminolevulinic acid, using derivative matrix isopotential synchronous fluorescence spectrometry.

Derivative Matrix-Isopotential Synchronous Spectrofluorimetry and Hantzsch Reaction: A Direct Route to Simultaneous Determination of Urinary δ-Aminolevulinic Acid and Porphobilinogen

“…Stock solutions for δ-ALA and PBG were prepared as 3 and 1 mM, respectively, in amber-colored volumetric flasks and were preserved in the refrigerator until use. Samples for both the analytes were prepared following a procedure reported previously ( Ajmal et al, 2019 ). Calibration plots were obtained by spiking different solutions with concentrations as 0–5 µM for δ-ALA and 0–15 µM for PBG.…”

“…For human bodies, their synthetic sequence leads to the production of haem. However, any abnormality in the haem biosynthetic pathway can give rise to a class of genetic disorders, known as the porphyrias ( Ajmal et al, 2019 ; Fujiwara et al, 2020 ; Jaramillo-Calle et al, 2021 ). The porphyrias are broadly categorized as either acute or non-acute.…”

“…Capitalizing on our previous knowledge regarding the porphyrins and the porphyria ( Huang et al, 2010 ; Shindi et al, 2010 ; Liu et al, 2012 ; Ajmal et al, 2019 ), we combine derivative matrix-isopotential synchronous fluorescence spectrometry (DMISFS) and the Hantzsch reaction to eliminate the long-standing problems of interference and laborious pre-analytical purifications for the simple, speedy and simultaneous determination of δ-ALA and PBG in the urine. While it is common to use the Hantzsch reaction for the fluorescent detection of δ-ALA, to our knowledge, there exists no precedent for either the detection of PBG alone or simultaneously with δ-ALA involving Hantzsch reaction or DMISFS.…”

Natural 5-Aminolevulinic Acid: Sources, Biosynthesis, Detection and Applications

“…Matrix-isopotential synchronous fluorescence spectra were recorded along a matrix-isopotential trajectory, which combines the points of equal intensity in theoretical 3D contours. Maximum sensitivity and appropriate selectivity were ensured by the study of the experimental variables in the d-ALA bands, centered at its excitation and emission maxima (392.6 and 464.5 nm) (Ajmal et al, 2019). This method was comparable to conventional high performance liquid chromatography-fluorescence, with a detection limit of 5.4 ppb and lower linear-range limit of 18 ppb.…”

“…The de novo quantification of intracellular and extracellular 5-ALA by monitoring the fluorescence of sfGFP fused to RshemA was also explored using dual promoters and dual plasmids (Tan S. I. et al, 2019). Additionally, to increase the understanding of the regulatory mechanism of 5-ALA in higher organisms, matrix isopotential synchronous fluorescence spectrometry and the first derivative technique were combined for the direct determination of δ-ALA in urine samples (Ajmal et al, 2019). The fluorescent derivatization of 5-ALA was based on the Hantzsch reaction.…”