Promotion of Hair Regrowth by Transdermal Dissolvable Microneedles Loaded with Rapamycin and Epigallocatechin Gallate Nanoparticles.

Interest in transdermal delivery methods for stimulating hair regrowth has been increasing recently. The microneedle approach can break the barrier of the stratum corneum through puncture ability and improve drug delivery efficiency. Herein, we report a dissolvable microneedle device for the co-delivery of rapamycin and epigallocatechin gallate nanoparticles that can significantly promote hair regeneration. Compared with the mice without any treatment, our strategy can facilitate hair growth within 7 days. Higher hair shaft growth rate and hair follicle density with inconspicuous inflammation were exhibited in C57BL/6 mice, elucidating its potential for clinical application.

Recent advancements in noninvasive glucose monitoring and closed-loop management systems for diabetes.

Diabetes can cause many complications, and has become one of the most common diseases that may lead to death. Currently, the number of diabetics continues to increase year by year. Thus, it is very important and highly desirable to monitor, control and cure diabetes. However, such management usually require long-term blood glucose monitoring and regular medication to reduce the risk of many complications. In order to provide patients with more effective and more convenient treatments, a portable, miniaturized, intelligent, painless and automatic closed-loop system is highly required and many related research studies have recently been reported. It is the right time and important to provide a summary in this field. Here, this review covers important parts of a closed-loop management system for diabetes, including the principle of electrochemical sensing of glucose, recent progress of noninvasive glucose monitoring technology, and its applications in wearable glucose sensors. Moreover, the latest advancements in an insulin delivery system and a diabetic closed-loop management system are also presented in detail. Finally, challenges and perspectives for an artificial pancreas are also presented. We believe that with the innovative glucose monitoring technology and the optimization of the drug delivery system, the closed-loop management system for diabetes will make much progress in the near future.

Crosstalk-Free, Stretching-Insensitive Sensor Based on Arch-Bridge Architecture for Tactile Mapping with Parallel Addressing Strategy toward Million-Scale-Pixels Processing.

In the field of biomimetic electronics, flexible sensors with both high resolution and large size are attracting a lot of attention. However, attempts to increase the number of sensor pixels have been thwarted by the need for complex inner circuits and the resulting interferences with the output. Technological challenges, such as real-time spatiotemporal mapping and long-time reliability, must be resolved for large-scale sensor matrices. This paper reports a simple and robust sensor with an arch-bridge architecture (ABA) to address these challenges. The device, which consists of an anti-icing all-transparent material system, is fabricated by immobilizing ABA ionic arrays on predefined grooves on the substrate. It systematically integrates ABA structure-designing, resistance-position-sensing, and parallel-addressing logic, allowing for an improvement of three orders of magnitude in the scanning speed (million-scale pixels) without logical "diagnose confusion." In addition, it can withstand 100 000 stretching cycles without functional failure. It is also resistant to interferences from stretching. humidity, wet surfaces, and power lines. The proposed strategy is envisaged to serve as a general solution for high-density, large-area tactile sensors in various applications.

Improved Therapeutic Efficiency against Obesity through Transdermal Drug Delivery Using Microneedle Arrays.

In this paper, we prepared patches that were composed of a degradable microneedle (MN) array with a soft backing provided for the skin tissue. We then performed a transdermal delivery of anti-obesity drugs to evaluate the effectiveness of ß3 adrenergic receptor CL316243 in obesity treatment in overweight mice induced by a high-fat diet. Eighty male National Institutes of Health (NIH) mice were randomly divided into four obese groups or the control group. The obesity groups were given a high-fat diet for 15-18 weeks to establish an obese model. Afterward, the obese groups were divided into the following four groups: the control group, the unloaded MN group, the CL-316243 MN group, and the injection group. For the injection group, the group of mice was injected subcutaneously with CL316243 (1 mg/(kg·day)) for 15 days. Furthermore, the CL-316243 MN group was given a lower dose (0.1 mg/(kg·day)) for 15 days. After weighing the mice, we used Western blotting to detect the expression of uncoupling protein 1 (UCP1) in the adipose tissue around the mouse viscera. The results stated that the weight of the CL-316243 MN group and the injection group dropped, and the UCP1 protein expression of brown adipose tissue (BAT) significantly increased. The results demonstrated the ß3 adrenergic receptor agonist CL316243 could be carried into the body through MN, and the dose applied was considerably smaller than the injection dose. The reason for this may arise from the CL-316243 being delivered by MN arrays to subcutaneous adipose tissue more efficiently, with an even distribution, compared to that of the injection dose. This technique provides a new and feasible way to treat obesity more effectively.