Photolysis of aqueous solutions of aniline-2,5-disulfonic acid: steady state and laser flash photolysis studies.

Photochem Photobiol Sci

Laboratoire de Phytochimie Moléculaire et Macromoléculaire, Umr CNRS 6505, Université Blaise Pascal, F-63177 Aubière Cedex.

Published: July 2002

The photochemical behaviour of aniline-2,5-disulfonic acid (ADSA) in aqueous solutions upon excitation at 254 nm, 310 nm and 334 nm has been studied. A specific phototransformation into o-anilinesulfonic acid (o-AS) via a desulfonation process was observed. Such a reaction was efficiently inhibited by molecular oxygen. The quantum yield was found to be 0.46 and 9.0 x 10(-3) in deoxygenated and oxygenated solutions, respectively. This inhibition was shown to result from an energy transfer process to oxygen through the formation of the lowest triplet excited state as demonstrated by a nanosecond laser flash photolysis study. The bimolecular quenching rate constant of the triplet state by oxygen is found to be 2.5 x 10(9) mol(-1) L s(-1). A mechanism taking into account the experimental results is proposed for the photochemical desulfonation of aniline-2,5-disulfonic acid.

Download full-text PDF

Source
http://dx.doi.org/10.1039/b202582eDOI Listing

Publication Analysis

Top Keywords

aniline-25-disulfonic acid
12
aqueous solutions
8
laser flash
8
flash photolysis
8
photolysis aqueous
4
solutions aniline-25-disulfonic
4
acid
4
acid steady
4
steady state
4
state laser
4

Similar Publications

This case describes a patient with pancreatic exocrine insufficiency and persistently elevated serum vitamin B12 concentrations that were not due to supplementation or associated with hepatic or hematological pathology. Laboratory investigations suggested the presence of macro-B12 as the cause of this patient's raised serum vitamin B12. Macro-B12 is often formed when vitamin B12-vitamin binding proteins (transcobalamin and haptocorrin) complex with immunoglobulins.

View Article and Find Full Text PDF

Background/aims: Certain sociodemographic groups are routinely underrepresented in clinical trials, limiting generalisability. Here, we describe the extent to which enriched enrolment approaches yielded a diverse trial population enriched for older age in a randomised controlled trial of a blood-based multi-cancer early detection test (NCT05611632).

Methods: Participants aged 50-77 years were recruited from eight Cancer Alliance regions in England.

View Article and Find Full Text PDF

Background: Diabetes mellitus is associated with morphological and functional impairment of the heart primarily due to lipid toxicity caused by increased fatty acid metabolism. Extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) have been implicated in the metabolism of fatty acids in the liver and skeletal muscles. However, their role in the heart in diabetes remains unclear.

View Article and Find Full Text PDF

tiRNA-Gln-CTG is Involved in the Regulation of Trophoblast Cell Function in Pre-eclampsia and Serves as a Potent Biomarker.

Front Biosci (Landmark Ed)

January 2025

Department of Obstetrics and Gynecology, Zhongda Hospital, School of Medicine, Southeast University, 210000 Nanjing, Jiangsu, China.

Background: Pre-eclampsia (PE) is a gestational disorder that significantly endangers maternal and fetal health. Transfer ribonucleic acid (tRNA)-derived small RNAs (tsRNAs) are important in the progression and diagnosis of various diseases. However, their role in the development of PE is unclear.

View Article and Find Full Text PDF

Hydroxyapatite Chitosan Gradient Pore Scaffold Activates Oxidative Phosphorylation Pathway to Induce Bone Formation.

Front Biosci (Landmark Ed)

January 2025

Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Fujian Medical University, Fujian Provincial Key Laboratory of Stomatology, National Regional Medical Center, Binhai Campus of The First Affiliated Hospital, 350005 Fuzhou, Fujian, China.

Background: In this study, we prepared a porous gradient scaffold with hydroxyapatite microtubules (HAMT) and chitosan (CHS) and investigated osteogenesis induced by these scaffolds.

Methods: The arrangement of wax balls in the mold can control the size and distribution of the pores of the scaffold, and form an interconnected gradient pore structure. The scaffolds were systematically evaluated and for biocompatibility, biological activity, and regulatory mechanisms.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!