A novel fluorescent pH indicator for the acidic range.

S Marchesini; S Gatt; V Agmon; M L Giudici; E Monti

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PubMed · 1417891

A novel fluorescent pH indicator for the acidic range.

S Marchesini·S Gatt·V Agmon·M L Giudici·E Monti

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Abstract

Reaction of a commercial preparation of lissamine-rhodamine B sulfonyl chloride with primary amines gives rise to two sulfonamide derivatives, of which one behaves as a pH indicator with maximal fluorescence emission in the acidic range and a pKa of about 4.6. The structure of this derivative and the mechanism of fluorescence dependence on pH, elucidated by means of NMR, is presented.

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Acids Amines Hydrogen-Ion Concentration Isomerism Magnetic Resonance Spectroscopy Molecular Structure Rhodamines Spectrometry, Fluorescence Journal Article Research Support, Non-U.S. Gov't

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S Marchesini, S Gatt, V Agmon, M L Giudici, E Monti. 1992. A novel fluorescent pH indicator for the acidic range.. https://pubmed.ncbi.nlm.nih.gov/1417891/

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