As the number of people with diabetes continues to increase, the use of high-performing blood glucose testing devices for blood glucose management is critical. Therefore, a flexible micronedle sensor (MNs sensor) based on flexible micronedle array structure (MNs array) is proposed in this study, inspired by the ultra-fast water absorption characteristics of straw, which can be used to quickly, conveniently and noninvasculatively detect glucose concentration in human interstitium fluid (ISF). The MNs sensor is the composite of flexible MNs array and highly sensitive detection electrode. The MNs sensor has excellent mechanical properties, the maximum pressure is 69.2 N (4 times the average), the compressive strength is 88.13 MPa (1.88 times the average), and the fracture compression ratio is 194.7 %(3.36 times the average). These properties enable MN sensors to penetrate the stratum corneum in complete form while extracting ISF quickly and consistently. Meanwhile, the MN sensor has the highly sensitivity (1826.75nA mM −1 cm −2 , 4.72 times the average value). It has a wider detection range (1 mM-30 mM) and faster detection (30 s) than existing MN glucose detectors. In addition, the MN sensor has excellent anti-interference performance and can accurately detect glucose concentration in the case of multiple disturbances. This work lays a foundation for the development of a new painless, real-time monitoring and high accuracy blood glucose detection system.
Shulin Shen,Aiqun Wan,Yan Wang,Linxiao Liu,Yao Yao,Jiaqi Weng,Tong Zhu,Qingliang Yang,Qinying Yan
Transdermal drug delivery systems for rheumatoid arthritis (RA) have garnered substantial attention due to their great potential to overcome limitations observed in conventional oral or injection strategies, including limited selectivity and adverse effects on extra-articular tissues. Microneedles (MNs) appear to be highly desirable carriers for transdermal drug delivery of RA. However, microneedles typically are unable to keep up with the flexibility of joints, which decreases the effectiveness of administration. In this study, we developed a flexible microneedles (FMNs) delivery system. And gelatin was employed for the fabrication of flexible backings for microneedles owing to its excellent ductility and biocompatibility . We achieved synergistic photothermal-chemotherapy of RA by incorporating the chemical drug Tacrolimus (TAC) and the photothermal agent gold nanorods (AuNRs) into dissolving microneedles. Results showed a high mechanical strength of the proposed FMNs. In the animal model of adjuvant-induced arthritis (AA), it is indicated that the prepared FMNs inhibited the expression of related inflammatory cytokines such as IL-1ß and TNF-α while enhancing bone repair and other related factors. Thus, the combination therapy of FMNs-mediated hyperthermia and chemotherapy can serve as a novel and synergistic treatment option for RA.