Supramolecular Phase-Selective Gelation by Peptides Bearing Side-Chain Azobenzenes: Effect of Ultrasound and Potential for Dye Removal and Oil Spill Remediation

International Journal of Molecular Sciences

Jürgen Bachl¹  Stefan Oehm¹  Judith Mayr¹  Carlos Cativiela²  José Juan Marrero-Tellado³  David D໚z D໚z¹  John George Hardy⁴ 

[1] Institut für Organische Chemie, Universität Regensburg, Universitätsstr. 31, Regensburg 93053, Germany; E-Mails:;Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-University of Zaragoza, 50009 Zaragoza, Spain; E-Mail:;Departamento de Química Orgánica, IUBO, “Antonio González”, Universidad de La Laguna, Astrofísico Francisco Sánchez 2, 38206 La Laguna, Spain; E-Mail:Institut für Organische Chemie, Universität Regensburg, Universitätsstr. 31, Regensburg 93053, Germany;

关键词: peptide;    azobenzene;    side-chain functionalization;    organogel;    phase-selective gelation;    dye removal;    oil spill;   

DOI  :  10.3390/ijms160511766

来源: mdpi

【 摘 要 】

Phase selective gelation (PSG) of organic phases from their non-miscible mixtures with water was achieved using tetrapeptides bearing a side-chain azobenzene moiety. The presence of the chromophore allowed PSG at the same concentration as the minimum gelation concentration (MGC) necessary to obtain the gels in pure organic phases. Remarkably, the presence of the water phase during PSG did not impact the thermal, mechanical, and morphological properties of the corresponding organogels. In the case of miscible oil/water mixtures, the entire mixture was gelled, resulting in the formation of quasi-hydrogels. Importantly, PSG could be triggered at room temperature by ultrasound treatment of the mixture or by adding ultrasound-aided concentrated solution of the peptide in an oil-phase to a mixture of the same oil and water. Moreover, the PSG was not affected by the presence of salts or impurities existing in water from natural sources. The process could be scaled-up, and the oil phases (e.g., aromatic solvents, gasoline, diesel fuel) recovered almost quantitatively after a simple distillation process, which also allowed the recovery and reuse of the gelator. Finally, these peptidic gelators could be used to quantitatively remove toxic dyes from aqueous solutions.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.