Delivery of liquid metal particles and tanshinone IIA into the pericardial cavity for myocardial infarction treatment†

Owing to their inherent flexibility and excellent biocompatibility, liquid metals (LMs) have been explored at the frontiers of clinical therapy. Herein, a LM and tanshinone IIA (TA) drugs were dispersed into sodium alginate (SA) solution by ultrasonication to prepare SA/LM/TA, which is an injectable biomaterial for stable drug release and intrapericardial injection for the treatment of myocardial infarction (MI). The SA/LM/TA has a low viscosity and can be injected smoothly using a syringe. In rat models of MI, we demonstrated that SA/LM/TA injection in the pericardial cavity is a biosafe and effective method to deliver a carrier containing LM particles and TA drugs for MI treatment. After injection, the drug release is slow and stable in the pericardial cavity, increasing the cardiac retention of drugs. After surgery and treatment for 7 days, the cardiac function of rats improved compared with the control group and the TA direct injection group. The intrapericardial injection of SA/LM/TA improves cardiac functions and mitigates cardiac remodeling post myocardial infarction of rats. Overall, the present study establishes a therapeutic strategy for treatment of myocardial infarction by intrapericardial injection of SA/LM/TA and expands the application categories of LM biomaterials in disease treatments.