阮长顺，中国科学院深圳先进技术研究院研究员/博士生导师，从事生物3D打印精准组织工程的交叉科学研究。先后主持国家级课题5项（包括国家自然科学基金优秀青年项目、科技部重点研发计划课题等），省市科技项目10余项。近年来，以一作或通讯作者（含共同）发表30余篇，包括The Innovation、Adv. Funct. Mater.、Adv. Sci.、Bone Res.、Biomaterials、Bioact. Mater.、Research等；申报中国发明专利30余项，国际PCT专利6项，获发明专利授权15项，部分实现转化；入选广东省科技创新青年拨尖人才，中国科学院青年促进创新委员会会员及深圳市高层次人才等；获深圳市自然科学二等奖（2/5）；担任中国生物材料学会生物材料先进制造分会秘书长、中国康复医学会修复重建外科专业委员会再生医学转化学组常务委员、中国医药生物技术协会3D打印分会委员等；担任生物制造领域国际期刊Bio-Des. Manuf 副主编。

Topic title: A Small-Molecule Polycationic Crosslinker Boosts Alginate-based Bioinks for Extrusion Bioprinting

Abstract:

The importance of bioink suitability for extrusion bioprinting tissue-like constructs cannot be overemphasized. Owing to their excellent accessibility, alginate (Alg) -based bioinks are widely used. However, the printability accuracy and post-printing stability of current Alg-based bioinks remain challenging, especially for large-size fabrication. Herein, an improvement strategy for pre-crosslinking and post-crosslinking of methacrylated Alg (AlgMA) bioinks in extrusion bioprinting was presented via introduction of methacrylated ε-polylysine (ε-PLMA) as a small-molecule polycationic crosslinker. Due to their electrostatic interaction and covalent bonding, ε-PLMA significantly reinforced the operability and prolonged stability of AlgMA bioinks, in comparison with single-molecule Ca2+ or large-molecule methacrylated gelatin as pre-crosslinkers. Meanwhile, attributed to their regulation of a charged microenvironment (-345.25 mV to 121.55 mV) and hydrophilicity (26.64° to 52.00°), the cells in bioprinted AlgMA/PLMA constructs demonstrated improved viability and vitality. Therefore, such a strategy of introducing small-molecule cationic crosslinker ε-PLMA is a promising booster for improving Alg-based extrusion bioprinting, potential to extend its biomedical applications.