A UV-Vis Spectrophotometric Method for the Estimation of Aldehyde Groups in Periodate-Oxidized Polysaccharides Using2,4-Dinitrophenyl Hydrazine

Abstract

In this study, efforts have been made to develop a simple approach to determine aldehyde content in periodate-oxidized polysaccharides. A UV-Vis analytical technique using 2,4-dinitrophenylhydrazine (DNPH) was employed to calculate the aldehyde content. When tested against compounds like acetaldehyde and formaldehyde with known aldehyde content, the DNPH method yielded accurate results. The DNPH assay was Analysis of Aldehydes in Polysaccharides by UV-Vis 339further utilized to analyze the aldehyde generation during periodate oxidation of pectin, a naturally occurring plant polysaccharide. It was found that the DNPH assay was sensitive even at low concentrations of aldehyde and yielded accurate results. Therefore, this method could be used to control and optimize reaction parameters during the periodate oxidation of polysaccharides.

Design of a heterogeneous enzymatic catalyst on chitosan: investigation of the role of conjugation chemistry in the catalytic activity of a Laccase from Trametes versicolor

“…So, in order to maintain the enzyme at the best experimental conditions for its stability, a value of 6.5 was chosen to carry out the oxidation reaction. To confirm the formation of carbonyl groups, a visible spectrophotometric method was used, based on the formation of sparingly soluble 2,4‐dinitrophenylhydrazones by the reaction of the sample with 2,4‐dinitrophenylhydrazine (2,4‐DNPH) in acidic medium . After hydrazones formation, it is necessary to treat them with an alkaline solution (NaOH 0.5 mol L ‐1 ) in order to fulfil two different purposes: first, the formation of a strongly absorbing orange anion of quinonoid structure, and, at the same time, the rapid decomposition of the unreacted DNPH into a corresponding colorless product.…”

“…After hydrazones formation, it is necessary to treat them with an alkaline solution (NaOH 0.5 mol L ‐1 ) in order to fulfil two different purposes: first, the formation of a strongly absorbing orange anion of quinonoid structure, and, at the same time, the rapid decomposition of the unreacted DNPH into a corresponding colorless product. The decolorization of unreacted DNPH results in a low blank and, thus, allows the analytes of interest to be exclusively measured . According to the experimental section, the percentage aldehyde content from five replicates was 2.5 ± 0.1%.…”

“…The decolorization of unreacted DNPH results in a low blank and, thus, allows the analytes of interest to be exclusively measured. 15,16 According to the experimental section, the percentage aldehyde content from five replicates was 2.5 ± 0.1%. In addition, in order to confirm that periodate oxidation did not affect the catalytic activity of laccase, measurements of activity before and after oxidation were carried out.…”

Effect of bacterial nanocellulose binding on the bactericidal activity of bovine lactoferrin

“…BNC membranes were immersed in a sodium periodate aqueous solution at a molar ratio 1:1, at 50 °C under mild agitation and protected from light. Periodate decomposition and concomitantly the percentage of BNC oxidation was analysed through the measurement of the optical density (at 290 nm) using an ultra-violet visible spectrometer [ 24 ]. In the end of the reaction, the oxidised BNC samples were thoroughly washed in sterile distilled water and immediately immersed in the bLF solutions.…”

Review of Spectrophotometric Methods for Determination of Formaldehyde

“…DNPH method is also used as a standard method, but requires HPLC before UV/VIS analysis and therefore, it is more expensive. This method requires expensive equipment and long time for colour development (3 hours) [58]. This method has also interferences from ozone oxides, NO and NO2.…”