Composite inclusion complexes containing sodium alginate composite nanogels for pH-responsive valnemulin hydrochloride release

• Published in: Journal of molecular structure 2022-09, Vol.1263, p.133054, Article 133054
• Main Authors: Liu, Jinhuan, Ju, Mujie, Guan, Ding, Song, Wei, Algharib, Samah Attia, Luo, Wanhe
• Format: Article
• Language: English
• Subjects: Antibacterial activity; Biosafety; Staphylococcus aureus small colony variants; Therapeutic efficacy; Valnemulin hydrochloride
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2022.133054

•The composite nanogels were synthesized by complexation and crosslinking.•The composite nanogels could enhance sustained and controlled release.•This study will provide new strategy for SCVs infection treatment. To increase the sustained and controlled release of valnemulin hydrochloride to the infected site of Staphylococcus aureus small colony variants (SCVs), pH-responsive valnemulin hydrochloride-loaded sodium alginate (SA) composite nanogels were firstly explored. The valnemulin hydrochloride was incorporated into the β-Cyclodextrins (CD) to form valnemulin hydrochloride-β-CD-inclusion complexes (IC) and IC might be taken up into SA hydrogels to form valnemulin hydrochloride-loaded SA composite nanogels. The formulation screening, characteristics, in vitro release, antibacterial activity, therapeutic effect, and biosafety of the valnemulin hydrochloride composite nanogels were performed. The optimized formula was made up of 10 mg/mL (SA) and 0.5 mg/mL (Ca2+). The mean particle diameter, polydispersity index, zeta potential, encapsulation efficiency, and loading capacity of the optimized formulation were 229.4±1.5 nm, 0.34±0.03, -33.2±2.2 mv, 84.3%±4.1%, and 8.5%±1.2%, respectively. Light microscope and scanning electron microscope images revealed that a cross-linked polymeric network was successfully prepared. The fourier transform infrared and powder X-ray diffraction showed that valnemulin hydrochloride composite nanogels were successfully formulated by complexation and ionic crosslinking. The valnemulin hydrochloride composite nanogels exhibited a biphasic pattern with sustained release of 61.4%±1.8% after 48 h at pH 5.5. The valnemulin hydrochloride composite nanogels might be used as a biocompatible preparation because of their non-toxic effect on the renal and liver. This study provides promising valnemulin hydrochloride composite nanogels to improve the treatment of the SCVs infection.