Advanced regenerative biomaterials for ischaemic stroke: a comprehensive therapeutic strategy

Ischaemic stroke is a major global public health problem, accounting for 62.4% of all strokes, with far-reaching consequences in terms of health burden in all regions. Nonetheless, a therapeutic window that is excessively narrow, coupled with restricted therapy modalities, has hindered the majority of patients from receiving effective treatment. With the rapid advancement of biomaterials technology, stroke treatment is being propelled towards a regenerative medicine era characterized by the tripartite collaboration of "materials, drugs, and cells". This review systematically reviews the cutting-edge advancements of hydrogels, nanoparticles, and hybrid systems in stroke repair. Hydrogels, with their injectable and self-healing properties, precisely fit the stroke cavity, creating a microenvironment for sustained release and cellular infiltration. Nanoparticles, engineered for size and surface functionality, traverse the blood-brain barrier to achieve multi-targeted synchronous regulation. Hybrid composites of hydrogels and nanoparticles integrate the strengths of both, offering mechanical support, biodegradability, and spatiotemporally controlled drug release. Crucially, biomaterials serve as intelligent delivery vehicles for stem cells, exosomes, and genes, significantly enhancing their retention rate, differentiation efficiency, and paracrine function in the ischaemic lesion, thereby remodelling the neurovascular unit. These advancements have great promise for improving therapeutic outcomes for stroke patients.