The reactivity of 5-amino-2,3-dihydro-phthalazine-1,4-dione (luminol) and phthalic hydrazide with hydroxyl radicals was studied. HO*-radicals were generated by the Fenton reaction as well as by water radiolysis. Both luminol and phthalic hydrazide react with hydroxyl radicals under intense chemiluminescence (CL) emission. However, exclusively the CL arising from phthalic hydrazide oxidation can be quenched by competition (e.g. by the addition of carbohydrates), whereas luminol CL is enhanced. The reactivities of both compounds with HO*-radicals were further studied by time-resolved spectroscopy (pulse radiolysis), competition methods, NMR spectroscopy and mass spectrometry. Whereas only slight differences were detectable by pulse radiolysis, the analysis of competition kinetics in the presence of p-nitroso-dimethylaniline (NDMA) gave a two-fold-enhanced reactivity for luminol (4.8 x 10(9) l mol(-1) s(-1)) in comparison to phthalic hydrazide (2.0 x 10(9) l mol(-1) s(-1)). NMR and mass spectrometric analyses revealed significant differences in the reactivity of HO*-radicals: whereas in luminol solutions hydroxylation of the aromatic ring system predominated, hydroxylated products were not detectable upon irradiation of phthalic hydrazide. A hypothetical mechanism is proposed which may explain the observed differences.
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Int J Biol Macromol
November 2024
Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, China. Electronic address:
Stem cell-based therapies show promise for clinically addressing circumferential tracheal defects (CTD) through tissue engineering. However, creating a tissue-engineered tracheal tube possesses a healthy cartilage matrix and intact tube structure remains a challenge. A solution lies in the use of an injectable hydrogel with shape adaptability and chondrogenic capacity, serving as a practical and dependable platform for tubular tracheal cartilage regeneration.
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June 2022
School of Chemistry and Chemical and Engineering, Guangxi University for Nationalities, Key Laboratory of Chemistry and Engineering of Forest Products, State Ethnic Affairs Commission, Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Guangxi Collaborative Innovation Center for Chemistry and Engineering of Forest Products, Key Laboratory of Guangxi Colleges and Universities for Food Safety and Pharmaceutical Analytical Chemistry, Nanning 530008, China.
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View Article and Find Full Text PDFPharmazie
April 2022
Drug Discovery and Development Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada.
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View Article and Find Full Text PDFRes Pharm Sci
December 2021
Department of Medicinal Chemistry and Isfahan Pharmaceutical Sciences Research Center, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, I.R. Iran.
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View Article and Find Full Text PDFArch Pharm (Weinheim)
August 2017
Institute of Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-University, Düsseldorf, Germany.
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