Electronic absorption spectra of ascorbic acid in water and water–dialkylsulfoxide mixtures

Abstract

A Gaussian analysis (LinkFit program) was used to deconvolute overlapping absorption bands due to neutral and anionic forms of ascorbic acid (AA). It has been shown that the neutral form of AA predominates in aqueous solutions of AA containing dialkylsulfoxides (DASO) because a hydrogen-bonded complex forms between DASO and AA molecules.

Electrochemiluminescence of Tris(2,2′-bipyridyl)ruthenium(II) with Ascorbic Acid and Dehydroascorbic Acid in Aqueous and Non-aqueous Solutions

“…DHA has no absorption peak in the investigated wavelength range, and the absorption spectrum of DHA did not change when the electrolysis potential was more positive than -0.6 V. However, absorption peaks appeared at 265 and 355 nm when the applied potential was more negative than -0.9 V. The UV absorption spectrum of HA -has been reported; excitation measurements indicated these species originated from the C=C bond and correspond to a π→π* transition. 28,29 The peaks at 265 and 355 nm under electrolysis at -1.2 V are attributed to HA -and A • -species, respectively, and are similar to those obtained in water. 28 These results indicate that the electrochemical product of reduction of DHA is A • -.…”

“…28,29 The peaks at 265 and 355 nm under electrolysis at -1.2 V are attributed to HA -and A • -species, respectively, and are similar to those obtained in water. 28 These results indicate that the electrochemical product of reduction of DHA is A • -. Part of the generated A • -was disproportionated to HA -, 23,29 which was simultaneously detected in absorption spectra.…”

Volumetric and UV absorption studies on understanding the solvation behavior of polyhydroxy solutes in l-ascorbic acid(aq) solutions at T=(288.15 to 318.15)K

“…The UV absorbance of L-ascorbic acid results in p ? p ⁄ transition due to the excitation of the C@C bond (Markarian & Sargsyan, 2011) and low intensity absorption band of C@O (keto group) leads to n ? p ⁄ transition (Williams & Fleming, 1988).…”

Studies on the Reduction of Dehydroascorbic Acid by Glutathione in the Presence of Aquahydroxocobinamide

“…Changes in UV/Vis spectra for the reactions are completely the same (Figure and Figure S1) and indicate an increase in the absorbance at 265 nm. The UV/Vis spectrum of the product coincides with that of ascorbic acid . We found that H 2 OCbl has no influence on the rate of the reaction (Figure S2), whereas (HO – )(H 2 O)Cbi(III) distinctly accelerates the generation of ascorbic acid (Figure ).…”