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Updated: May 12, 2026
A Technical Guide for Performing Spectroscopic Measurements on Metal-Organic Frameworks
Published on: April 28, 2023
STRUCTURE OF PORPHYRIN TPPS4 AND ITS INTERACTION WITH METAL IONS AS ELUCIDATED BY 1H NMR AND UV-VISIBLE SPECTRA
Zhiyan Song1, Adegboye O Adeyemo, Jannie Baker
1Department of Natural Sciences, Savannah State University, Savannah, GA 31404, USA.
None:
Porphyrins are a group of tetrapyrrole pigments. Physical and chemical properties of porphyrins are often related to their compositions and structures. We conducted 1H solution NMR and UV-visible spectral analysis to characterize the structural feature of a water-soluble, synthetic porphyrin i.e. tetrakis (p-sulfonatophenyl) porphyrin, TPPS4, and its interaction with different metal ions in aqueous solutions. The results indicate that tetrapyrrole and tetraphenyl rings in TPPS4 molecule form a co-planar electron conjugation system; transition-metal ions show stronger binding capacity than alkali and alkali-earth metal ions; the relative stabilities of TPPS4-metal ion complexes can be well assessed by NMR and UV-visible spectral data.
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