Fluorometric apoprotein titration of urinary riboflavin

Abasic‐Site‐Containing Oligodeoxynucleotides as Aptamers for Riboflavin

“…Although the fact that only four nucleobases are available for our design scheme may necessitate some synthetic modification of the nucleobases in order to make it suitable for binding with a large number of ligands, our DNA aptamer may have some advantages, such as its easy and low‐cost synthesis and its higher chemical stability relative to typical RNA aptamers. These features of the AP‐site‐based DNA aptamer would allow various kinds of analytical applications, including the isolation of riboflavin from natural sources26 and the determination of riboflavin in aqueous samples 27–29. Moreover, our system can also be applied to the analysis of thymidine‐related SNPs, for which riboflavin functions as a thymidine‐selective fluorescence ligand and the complexation‐induced quenching of its fluorescence is utilized to detect the single‐base mutation (see the Supporting Information).…”

Capillary Microfluidics for Monitoring Medication Adherence

“…[42] Nowadays,s martphones,s imple optical components, and image processing algorithms may remedy some of these issues.I na ddition, fluorometric titration measurements that rely on fluorescence of riboflavin alone or after quenching by riboflavin-binding protein can significantly improve measurements of riboflavin in human urine samples (Figure 3f). [43,44] Riboflavin can also be converted to lumichrome,astronger fluorescent compound, by riboflavinase.…”

Fluorometric Riboflavin Titration in Plasma by Ribof lavin_-Binding Apoprotein as a Method for Vitamin B₂ Status Assessment

“…Riboflavin-binding apoprotein was isolated from egg white [6] and lyophilized. According to sodium dodecyl sulfate-polyacrylamide gel electrophoresis [9], its purity was 80%.…”

“…The urinary riboflavin excretion was determined by fluorometric riboflavin-binding apoprotein titra tion [6]. For the plasma riboflavin level determination, two quite different volumes o f plasma samples were used: ( l) a macrovolume and (2) a microvolume, de pending upon the type o f the fluorometric cuvette employed for the measurement.…”

“…Meanwhile, the riboflavin plasma level reflects the immediate dietary intake o f the vitamin [2], For its deter mination three methods may be used: the multistage physicochemical one based on the phenomenon o f riboflavin fluorescence egg white riboflavin-binding apoprotein has been proposed [6,7]. This apoprotein has a higher affinity for riboflavin (about 1.3 nM ) than for the flavin coenzymes flavin mononu cleotide and flavin adenine dinucleotide.…”