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International audience; In this study, we report on the fabrication of photo/thermo dual stimulus-responsive liquid marbles (LMs) that can be disrupted by light irradiation and/or heating. To stabilize the LMs, we synthesized micrometer-sized stearic acid (SA) particles coated with overlayers of polypyrrole (PPy) by aqueous chemical oxidative seeded dispersion polymerization. The SA/PPy core–shell particles could adsorb at the air–water interface to stabilize LMs by rolling water droplets on the particle powder bed. The presence of SA, known as a phase-change material, which undergoes a transition from solid to liquid by heating, and PPy, which can transduce light to heat, gives rise to the photo and thermo dual stimulus-responsive characters of the LMs. The disruption of the LMs could be induced in a cascade manner: light irradiation on the LM induced a temperature increase, followed by melting of the SA component on the LM surface, leading to its disruption and release of the inner water. The disruption time is linked to the PPy loading and light irradiation power, and it can be tuned from quasi-instantaneous to a few tens of seconds. The melting of SA due to a light-induced phase change from the solid to liquid state is a new mechanism to trigger the disruption of LMs. We finally demonstrated two applications of the LMs as a light-responsive microreactor and a sensor.

To improve the degradability and operability of conventional bone graft materials, we fabricated a water-oil emulsion based on α-tricalcium phosphate (α-TCP) bone paste. Simvastatin, a lipophilic hyperlipidemia treatment agent, reportedly enhances the expression of bone morphogenetic protein-2 and subsequent bone formation. Accordingly, we assessed the bone forming effects of α-TCP bone-paste containing simvastatin in rat cranial bone defects. Bone paste exhibited porous structure and generation of hydroxyapatite after solidification. X-ray image analysis and histological examination were carried out after implantation of bone paste into rat skull defect. The results showed that new bone was formed after implantation of bone paste containing simvastatin. In particular, bone volume in the 0.1 mg simvastatin group was significantly promoted when compared to controls (no implantation). No bone paste residue was observed in the bone defect at 4 weeks after surgery. Therefore, α-TCP bone paste containing simvastatin is degradable and beneficial for bone tissue engineering.