An injectable carrier for spatiotemporal and sequential release of therapeutic substances to treat myocardial infarction.

Myocardial infarction (MI) has become the primary cause of cardiovascular mortality, while the current treatment methods in clinical all have their shortcomings. Injectable biomaterials have emerged as a promising solution for cardiac tissue repair after MI. In this study, we designed a smart multifunctional carrier that could meet the treatment needs of different MI pathological processes by programmatically releasing different therapeutic substances. The carrier could respond to inflammatory microenvironment in the early stage of MI with rapid release of curcumin (Cur), and then sustained release recombinant humanized collagen type III (rhCol III) to treat MI. The rapid release of Cur reduced inflammation and apoptosis in the early stages, while the sustained release of rhCol III promoted angiogenesis and cardiac repair in the later stages. In vitro and in vivo results suggested that the multifunctional carrier could effectively improve cardiac function, promote the repair of infarcted tissue, and inhibit ventricular remodeling by reducing cell apoptosis and inflammation, and promoting angiogenesis in the different pathological processes of MI. Therefore, this programmed-release carrier provides a promising protocol for MI therapy.

Graphene Oxide-Template Gold Nanosheets as Highly Efficient Near-Infrared Hyperthermia Agents for Cancer Therapy.

INTRODUCTION: Near-infrared (NIR) hyperthermia agents are promising in cancer photothermal therapy due to their deeper penetration ability and less side effects. Spherical gold nanoshell and graphene-based nanomaterials are two major NIR hyperthermia agents that have been reported for photothermal therapy of cancer. Herein, we constructed a two-dimensional graphene oxide-template gold nanosheet (GO@SiO2@AuNS) hybrid that could destruct cancer cells with efficient photothermal effect. METHODS: Graphene oxide was coated with a layer of mesoporous silica, which provided binding sites for gold seeds. Then, seed-growth method was utilized to grow a layer of gold nanosheet to form the GO@SiO2@AuNS hybrid, which possessed great biocompatibility and high photothermal conversion efficiency. RESULTS: With the irradiation of NIR laser (808 nm) with low power density (0.3 W/cm2), GO@SiO2@AuNS hybrid showed a photothermal conversion efficiency of 30%, leading to a temperature increase of 16.4 °C in water. Colorectal cancer cells (KM12C) were killed with the treatment of GO@SiO2@AuNS hybrid under NIR irradiation. CONCLUSION: The GO@SiO2@AuNS hybrid may expand the library of the 2D nanostructures based on gold for cancer photothermal therapy.