Antimicrobial Activity with Enhanced Mechanical Properties in Phenylalanine-Based Chiral Coassembled Hydrogels: The Influence of Pyridine Hydrazide Derivatives

Auphedeous Y Dang-I; Tingting Huang; Nabila Mehwish; Xiao-Qiu Dou; Li Yang; Vincent Mukwaya; Chao Xing; Shuangjun Lin; Chuan-Liang Feng

doi:10.1021/acsabm.0c00075

Antimicrobial Activity with Enhanced Mechanical Properties in Phenylalanine-Based Chiral Coassembled Hydrogels: The Influence of Pyridine Hydrazide Derivatives

ACS Appl Bio Mater. 2020 Apr 20;3(4):2295-2304. doi: 10.1021/acsabm.0c00075. Epub 2020 Mar 10.

Authors

Auphedeous Y Dang-I¹, Tingting Huang², Nabila Mehwish¹, Xiao-Qiu Dou¹, Li Yang¹, Vincent Mukwaya¹, Chao Xing¹, Shuangjun Lin², Chuan-Liang Feng¹

Affiliations

¹ State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiaotong University, Dongchuan Road 800, 200240 Shanghai, China.
² School of Life Sciences and Biotechnology, Shanghai Jiaotong University, Dongchuan Road 800, 200240 Shanghai, China.

PMID: 35025281
DOI: 10.1021/acsabm.0c00075

Abstract

Hydrazide derivatives are known to display a wide range of biological properties including antimicrobial activities, hence making them desirable candidates for soft biomaterials. Herein, we report chiral supramolecular coassembled hydrogels obtained from two phenylalanine gelators (L/DPF and B2L/D) and two dicarbohydrazide molecules (pyridine-2,6-dicarbohydrazide (PDH) and (2,2'-bipyridine)-5,5'-dicarbohydrazide (BDH)) that exhibited enhanced mechanical properties, chirality modulation, and antimicrobial activity. Four lines of coassembled hydrogels were obtained (i.e., L/DPF-PDH, L/DPF-BDH, B2L/D-PDH, and B2L/D-BDH) through hydrogen bonding and π-π stacking with some level of an interpenetrating network, as revealed by the structural characterization analysis. Mechanical properties were significantly improved, especially in the case of hybrid gels involving BDH, with improved average elastic modulus (G') values of 3430 and 3167 Pa for DPF-BDH and B2D-BDH (1:3, molar concentration) over 140 and 1680 Pa for DPF and B2D gelators, respectively. This was attributed to the improved π-π stacking and interpenetrating network due to the bipyridine group and its ease to form fibrous precipitates in the process of heating and cooling to room temperature. PDH, on the other hand, was able to modulate chirality in the L/DPF gelator due to its more planar and less bulky nature and showed antimicrobial activity against Pseudomonas aeruginosa (Gram-negative). Interestingly, when PDH was coassembled with the B2L/D gelator, the hybrid gels exhibited antimicrobial activity against Staphylococcus aureus (Gram-positive) and P. aeruginosa (Gram-negative) by virtue of a synergistic effect of the gelator and the azomethine group of PHD. Hence, by moving from bipyridine (BDH) to pyridine (PDH) as a core structure in the hydrazide molecules, the resulting hybrid hydrogels exhibited desirable properties of antimicrobial activity and improved mechanical attributes.

Keywords: antimicrobial activity; chirality; coassembly; mechanical strength; supramolecular.