Preparation and Characterization of Attractive Poly(amino acid)Hydrogels Based on 2-Ureido-4[1H]-pyrimidinone

• 作者: Zhen Shi Qi Wang Gui-Fei Li Yu-Feng Shou Hong-Jie Zong Shi-Feng Yan Kun-Xi Zhang Jing-Bo Yin
• 来源期刊: 高分子科学（英文版）
• 年，卷（期）: 2021,（3）
• 所属期刊栏目: ARTICLES
• 页码范围: 327-336
• 页数: 10页
• 语种: 英文

摘要

Self-healing hydrogels with the shear-thinning property are novel injectable materials and are superior to traditional injectable hydrogels.The self-healing hydrogels based on 2-ureido-4[1H]-pyrimidinone(UPy)have recently received extensive attention due to their dynamic reversibility of UPy dimerization.However,generally,UPy-based self-healing hydrogels exhibit poor stability,cannot degrade in vivo and can hardly be excreted from the body,which considerably limit their bio-application.Here,using poly(l-glutamic acid)(PLGA)as biodegradable matrix,branching α-hydroxy-ω-amino poly(ethylene oxide)(HAPEO)as bridging molecule to introduce UPy,and ethyl acrylate polyethylene glycol(MAPEG)to introduce double bond,the hydrogel precursors(PMHU)are prepared.A library of the self-healing hydrogels has been achieved with well self-healable and shear-thinning properties.With the increase of MAPEG grafting ratio,the storage modulus of the self-healing hydrogels decreases.The self-healing hydrogels are stable in solution only for 6 h,hard to meet the requirements of tissue regeneration.Consequently,ultraviolet(UV)photo-crosslinking is involved to obtain the dual crosslinking hydrogels with enhanced mechanical properties and stability.When MAPEG grafting ratio is 35.5％,the dual crosslinking hydrogels can maintain the shape in phosphate-buffered saline solution(PBS)for at least 8 days.Loading with adipose-derived stem cell spheroids,the self-healing hydrogels are injected and self-heal to a whole,and then they are crosslinked in situ via UV-irradiation,obtaining the dual crosslinking hydrogels/cell spheroids complex with cell viability of 86.7％±6.0％,which demonstrates excellent injectability,subcutaneous gelatinization,and biocompatibility of hydrogels as cell carriers.The novel PMHU hydrogels crosslinked by quadruple hydrogen bonding and then dual photo-crosslinking of double bond are expected to be applied for minimal invasive surgery or therapies in tissue engineering.