The binding stoichiometry and binding equilibria of human serum albumin with water-soluble four free base porphyrins and six chloroiron (+3) porphyrins have been determined in 0.1M phosphate buffer, pH 7.2, by fluorescence quenching and filtration methods. The binding stoichiometry is observed to be 1:1, porphyrin to protein. The dissociation constants, Kd, between the porphyrins and the protein are found to be 1-4 microM. A binding mechanism between the protein and the porphyrins has been presented.

The binding stoichiometry and equilibria of three polycationic water-soluble porphyrins with human serum albumin (HSA) have been determined by fluorescence quenching and filtration methods in 0.1M phosphate buffer, pH 7.2 at 25 degrees. For one porphyrin the binding equilibrium was also measured by measuring the lifetime of tryptophan and also by measuring the polarization of bound porphyrin. Energy transfer between the porphyrin and the tryptophan residue of HSA has been studied.

ChemInformVolume 19, Issue 6 Organic Dyes ChemInform Abstract: Asymmetric Porphyrins. Part 1. Synthesis, Characterization, and Physicochemical Properties of Phenyl/4-Benzyloxyphenyl 5,10,15,20-Substituted Porphyrins. N. DATTA-GUPTA, N. DATTA-GUPTA Dep. Nat. Sci., South Carolina State Coll., Orangeburg, SC 29117, USASearch for more papers by this authorD. MALAKAR, D. MALAKAR Dep. Nat. Sci., South Carolina State Coll., Orangeburg, SC 29117, USASearch for more papers by this authorL. RICE, L. RICE Dep. Nat. Sci., South Carolina State Coll., Orangeburg, SC 29117, USASearch for more papers by this authorS. RIVERS, S. RIVERS Dep. Nat. Sci., South Carolina State Coll., Orangeburg, SC 29117, USASearch for more papers by this author N. DATTA-GUPTA, N. DATTA-GUPTA Dep. Nat. Sci., South Carolina State Coll., Orangeburg, SC 29117, USASearch for more papers by this authorD. MALAKAR, D. MALAKAR Dep. Nat. Sci., South Carolina State Coll., Orangeburg, SC 29117, USASearch for more papers by this authorL. RICE, L. RICE Dep. Nat. Sci., South Carolina State Coll., Orangeburg, SC 29117, USASearch for more papers by this authorS. RIVERS, S. RIVERS Dep. Nat. Sci., South Carolina State Coll., Orangeburg, SC 29117, USASearch for more papers by this author First published: February 9, 1988 https://doi.org/10.1002/chin.198806281AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume19, Issue6February 9, 1988 RelatedInformation

Abstract Three new porphyrins with sulfur functional groups, one of which is water-soluble, have been prepared. Their UV-visible absorption, fluorescence emission, and 1H NMR spectra as well as their copper(2+) insertion kinetics, pK3 values and first and second reduction potentials determined. For the water soluble porphyrin, its binding with human serum albumin (HSA) determined.

AbstractA complete series of five phenyl/4‐benzyloxyphenyl 5,10,15,20‐substituted porphyrin has been synthesized, characterized by analysis, Rf values, and proton‐nmr spectroscopy (pmr). Their physicochemical properties, namely ir spectra, absorption spectra, emission spectra, excited state life‐times, pK3 values, reduction potentials, and kinetics of Cu(+2) insertion, have been determined. Attempts have been made to correlate these physicochemical properties with the structures of the porphyrins.

To determine the pK3 value of porphyrins, a simple spectrofluorometric titration method has been developed. The porphyrin solution is titrated with perchloric acid. After each addition of acid, the porphyrin solution is excited at one suitable wave length and the emission intensity is measured at another suitable wave length. The pK3 values of twelve porphyrins have been determined. Nitrobenzene, toluene and water have been used as solvents. The pK3 values have been compared with the literature values. Attempt has been made to correlate the Cu+2 insertion kinetics of six porphyrins and their pK3 values.

AbstractDie Tetraphenylporphyrine (IIIa)‐(IIIc) werden nach bekannten Verfahren synthetisiert und spektroskopisch analysiert.

The 1:1 adduct formation between the zinc complex of meso-tetra-4-benzyloxyphenylporphine and pyridine have been studied in benzene, chlorobenzene, bromobenzene, toluene, acetophenone, methylbenzoate, anisole and nitrobenzene using absorption spectroscopy and water-jacketed cells. The binding equilibria were measured at 20, 30 and 40°C. Keq values of binding decrease with increasing temperature. The thermodynamic parameters have been calculated. Attempts have been made to explain the thermodynamic parameters.

Six tetraphenylporphyrins have been studied for their binding with human apohemoglobin and methemoglobin. Four showed binding with apohemoglobin, in a way hemin binds, to form analogs of recondtituted hemoglobin. Five porphyrins bound with methemoglobin, perhaps, through random ionic interaction.