Fluorescence study of some structural and compositional effects on the aggregation of hydrophobized hyaluronan

• Published in: Colloid and interface science communications Vol. 51; p. 100677
• Main Authors: Velcer, Tomáš, Mravec, Filip, Venerová, Tereza, Chang, Chien-Hsiang, Pekař, Miloslav
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2022
• Subjects: Critical aggregation concentration; Degree of substitution; Fluorescence; Hydrophobically modified hyaluronan; Pyrene; Fluorescence; Pyrene; Hydrophobically modified hyaluronan; Degree of substitution; Critical aggregation concentration
• ISSN: 2215-0382; 2215-0382
• DOI: 10.1016/j.colcom.2022.100677

The aggregation behavior of four samples of hydrophobically modified hyaluronan was examined in water and in 0.15 M NaCl. The samples differed in the length of their hydrocarbon modifying chains, degree of substitution, or hyaluronan molecular weight. The critical aggregation concentration was determined by fluorescence spectroscopy using pyrene as a probe. Aggregation was observed even with hyaluronan modified by a short alkyl chain (C6). The critical aggregation concentration decreased with increasing alkyl chain length and with increasing hyaluronan molecular weight at a comparable degree of substitution. Aggregation was detected over a rather broad concentration interval, indicating a progressive formation of aggregates. Two populations of aggregates were detected for the oleyl substitution. The addition of NaCl had only minor effect on the critical aggregation concentration. [Display omitted] •Critical aggregation concentration depends on alkyl and hyaluronan lengths.•Aggregation observed even with C6-alkyl modified hyaluronan.•Aggregation detected over a broader concentration interval.•Two populations of aggregates detected for the C18-alkyl substitution.