School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, 5000, Australia.
School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, 5000, Australia; Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, 5095, Australia.
Carbohydr Polym. 2019 Mar 1;207:143-159. doi: 10.1016/j.carbpol.2018.11.053. Epub 2018 Nov 19.
Thermoresponsive polymers have been used extensively for various applications including food additives, pharmaceutical formulations, therapeutic delivery, cosmetics and environmental remediation, to mention a few. Many thermoresponsive polymers have the ability to form physical hydrogel networks in response to temperature changes, which are particularly useful for emerging biomedical applications, including cell therapies, drug delivery systems, tissue engineering, wound healing and 3D bioprinting. In particular, the use of polysaccharides with thermoresponsive properties has been of interest due to their wide availability, versatile functionality, biodegradability, and in many cases, inherent biocompatibility. Naturally thermoresponsive polysaccharides include agarose, carrageenans and gellan gum, which exhibit upper critical solution temperatures, transitioning from a solution to a gel state upon cooling. Arguably, this limits their use in biomedical applications, particularly for cell encapsulation as they require raised temperatures to maintain a solution state that may be detrimental to living systems. Conversely, significant progress has been made over recent years to develop synthetically modified polysaccharides, which tend to exhibit lower critical solution temperatures, transitioning from a solution to a gel state upon warming. Of particular interest are thermoresponsive polysaccharides with a lower critical solution temperature in between room temperature and physiological temperature, as their solutions can conveniently be manipulated at room temperature before gelling upon warming to physiological temperature, which makes them ideal candidates for many biological applications. Therefore, this review provides an introduction to the different types of thermoresponsive polysaccharides that have been developed, their resulting hydrogels and properties, and the exciting applications that have emerged as a result of these properties.
温敏聚合物已被广泛应用于各种领域，包括食品添加剂、药物制剂、治疗药物传递、化妆品和环境修复等。许多温敏聚合物能够响应温度变化形成物理水凝胶网络，这对于新兴的生物医学应用特别有用，包括细胞治疗、药物传递系统、组织工程、伤口愈合和 3D 生物打印。特别是，具有温敏特性的多糖的使用引起了人们的兴趣，因为它们广泛存在、多功能、可生物降解，在许多情况下还具有固有生物相容性。天然温敏多糖包括琼脂糖、卡拉胶和结冷胶，它们表现出上临界溶解温度，在冷却时从溶液状态转变为凝胶状态。可以说，这限制了它们在生物医学应用中的使用，特别是在细胞包封方面，因为它们需要升高的温度来维持溶液状态，这可能对活细胞系统有害。相反，近年来在开发合成修饰的多糖方面取得了显著进展，这些多糖往往表现出较低的临界溶解温度，在升温时从溶液状态转变为凝胶状态。特别感兴趣的是具有室温到生理温度之间的较低临界溶解温度的温敏多糖，因为它们的溶液可以在室温下方便地操作，然后在升温到生理温度时凝胶化，这使它们成为许多生物应用的理想候选物。因此，本综述介绍了已开发的不同类型的温敏多糖、它们的水凝胶及其性质，以及由于这些性质而出现的令人兴奋的应用。
