Temperature-sensitive Hydrogel: An Effective Treatment for Nasal Drug Delivery Targeting the Brain.

The brain is highly protected by physiological barriers, in which the blood-brain barrier restricts the entry of most drugs. Intranasal drug delivery is a non-invasive way of drug delivery, which can cross the blood-brain barrier and achieve direct and efficient targeted delivery to the brain. Therefore, it has great po-tential in application to the treatment of brain diseases. Temperature-sensitive hydrogels undergo a solution-gel transition with temperature change, and the gel form has good mucosal adsorption properties in the nasal cavity, which is commonly used for targeted delivery of drugs for brain diseases. In this article, by introducing the transport mechanism of brain targeting after nasal administration, combined with the prescription design and basic performance study of temperature-sensitive nasal hydrogel, we summarized the research on the role that temperature-sensitive hydrogel plays brain targeting after via nasal administration, aiming to provide a reference for the development of therapeutic drugs for cerebral diseases and their clinical application. A graph-ical summary is shown in Fig. (1).