Vashahi Foad, Martinez Michael R, Dashtimoghadam Erfan, Fahimipour Farahnaz, Keith Andrew N, Bersenev Egor A, Ivanov Dimitri A, Zhulina Ekaterina B, Popryadukhin Pavel, Matyjaszewski Krzysztof, Vatankhah-Varnosfaderani Mohammad, Sheiko Sergei S
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3290, USA.
Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213, USA.
Sci Adv. 2022 Jan 21;8(3):eabm2469. doi: 10.1126/sciadv.abm2469.
Injectable hydrogels are desired in many biomedical applications due to their minimally invasive deployment to the body and their ability to introduce drugs. However, current injectables suffer from mechanical mismatch with tissue, fragility, water expulsion, and high viscosity. To address these issues, we design brush-like macromolecules that concurrently provide softness, firmness, strength, fluidity, and swellability. The synthesized linear-bottlebrush-linear (LBL) copolymers facilitate improved injectability as the compact conformation of bottlebrush blocks results in low solution viscosity, while the thermoresponsive linear blocks permit prompt gelation at 37°C. The resulting hydrogels mimic the deformation response of supersoft tissues such as adipose and brain while withstanding deformations of 700% and precluding water expulsion upon gelation. Given their low cytotoxicity and mild inflammation in vivo, the developed materials will have vital implications for reconstructive surgery, tissue engineering, and drug delivery applications.
可注射水凝胶因其对身体的微创植入以及引入药物的能力而在许多生物医学应用中备受青睐。然而，目前的可注射材料存在与组织机械性能不匹配、易碎、水分排出和高粘度等问题。为了解决这些问题，我们设计了刷状大分子，其同时具备柔软性、坚固性、强度、流动性和膨胀性。合成的线性-瓶刷-线性（LBL）共聚物有助于提高可注射性，因为瓶刷嵌段的紧密构象导致溶液粘度低，而热响应性线性嵌段允许在37°C时迅速凝胶化。所得水凝胶模拟了脂肪和大脑等超软组织的变形响应，同时能承受700%的变形，并在凝胶化时防止水分排出。鉴于其低细胞毒性和体内轻度炎症，所开发的材料将对重建手术、组织工程和药物递送应用具有重要意义。
