Hollow microgels and their hybrids have gained much attention in modern-day research because of their fascinating properties and potential applications. This article gives classification, preparation methods, properties and applications of hollow microgels and their hybrids in modern research. Some of the hollow microgels and their hybrids respond to change in specific environmental stimuli like pH, ionic strength and temperature of the medium. They are called smart polymer hollow microgels and smart hybrid microgels, respectively. This peculiar behaviour makes them a suitable candidate for their use in drug delivery, sensing, catalysis and many other fields. This review represents the current advancement along with future perspectives and suggestions for further research in this particular area.

中文翻译：

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中空微凝胶及其杂化物：分类、合成、表征、性质和应用

空心微凝胶及其混合物因其迷人的特性和潜在的应用而在现代研究中受到广泛关注。介绍了中空微凝胶及其杂化物的分类、制备方法、性质及其在现代研究中的应用。一些中空微凝胶及其混合物对特定环境刺激的变化做出反应，如介质的 pH 值、离子强度和温度。它们分别被称为智能高分子中空微凝胶和智能杂化微凝胶。这种奇特的行为使它们成为药物输送、传感、催化和许多其他领域的合适候选者。这篇综述代表了当前的进展以及对该特定领域进一步研究的未来观点和建议。