Cheng Guo Li

A Minimally Invasive Blood-Extraction System: Elastic Self-Recovery Actuator Integrated with an Ultrahigh- Aspect-Ratio Microneedle

A minimally invasive blood-extraction system is fabricated by the integration of an elastic self-recovery actuator and an ultrahigh-aspect-ratio microneedle. The simple elastic self-recovery actuator converts finger force to elastic energy to provide power for blood extraction and transport without requiring an external source of power. This device has potential utility in the biomedical field within the framework of complete micro-electromechanical systems.

Innovative polymeric system (IPS) for solvent-free lipophilic drug transdermal delivery via dissolving microneedles

Lipophilic drugs are potential drug candidates during drug development. However, due to the need for hazardous organic solvents for their solubilization, these drugs often fail to reach the pharmaceutical market, and in doing so highlight the importance of solvent free systems. Although transdermal drug delivery systems (TDDSs) are considered prospective safe drug delivery routes, a system involving lipophilic drugs in solvent free or powder form has not yet been described. Here, we report, for the first time, a novel approach for the delivery of every kind of lipophilic drug in powder form based on an innovative polymeric system (IPS). The phase transition of powder form of lipophilic drugs due to interior chemical bonds between drugs and biodegradable polymers and formation of nano-sized colloidal structures allowed the fabrication of dissolving microneedles (DMNs) to generate a powerful TDDS. We showed that IPS based DMN with powder capsaicin enhances the therapeutic effect for treatment of the rheumatic arthritis in a DBA/1 mouse model compared to a solvent-based system, indicating the promising potential of this new solvent-free platform for lipophilic drug delivery.

Anti-obesity effect of a novel caffeine-loaded dissolving microneedle patch in high-fat diet-induced obese C57BL/6J mice

Abstract Natural products such as caffeine have been found to be effective in reducing body weight through lipolysis. Here, we report the successful loading of caffeine onto dissolving microneedle following inhibition of its crystal growth by hyaluronic acid (HA), the matrix material of the dissolving microneedle (DMN). Further, the anti‐obesity activity of caffeine was evaluated in high‐fat diet‐induced obese C57BL/6J mice. After 6 weeks of caffeine loaded dissolving microneedle patch (CMP) administration, lipolysis improved significantly as shown by leptin and adiponectin activity, which resulted in considerable weight loss of about 12.8 ± 0.75% in high‐fat diet‐induced obese mice. Comparison of the levels of triglyceride, total cholesterol, high‐density lipoprotein (HDL)‐cholesterol, and low‐density lipoprotein (LDL)‐cholesterol after CMP administration with the initial levels in obese mice indicated significant anti‐obesity activity of CMP. These findings suggested that a novel CMP with an increased amount of caffeine loaded onto DMN has therapeutic activity against obesity. Graphical abstract Figure. No Caption available.