Diabetes patients cannot complete effective blood glucose regulation due to their impaired pancreatic function. At present, subcutaneous insulin injection is the only treatment for patients with type 1 and severe type 2 diabetes. However, long-term subcutaneous injection will cause patients with intense physical pain and lasting psychological burden. In addition, subcutaneous injection will lead to hypoglycemia risk to a large extent because of the uncontrollable release of insulin. In this work, we developed a glucosesensitive microneedle patch based on phenylboronic acid (PBA)modified chitosan (CS) particles and poly(vinyl alcohol) (PVA)/ poly(vinylpyrrolidone) (PVP) hydrogel for the efficient delivery of insulin. Meanwhile, through the double glucose-sensitive response process of CS-PBA particle and external hydrogel, the sudden release of insulin was well restrained, and a more persistent blood glucose control was achieved. Finally, the painless, minimally invasive, and efficient treatment effect of the glucose-sensitive microneedle patch indicated its great advantages as a new generation of injection therapy.

As a common oxidizer, ammonium perchlorate (AP) is an important component in composite solid propellants (CSPs). Ferrocene (Fc)‐based compounds are often selected as burning rate catalysts (BRCs) to catalyze AP decomposition owing to their excellent catalytic behavior. However, one of the drawbacks of Fc‐based BRCs is migration in CSPs. In this study, five Fc‐terminated dendrimers are designed and synthesized to improve the anti‐migration properties, and their chemical structures are confirmed systemically by the related spectra characterization techniques. Moreover, the redox performance, catalytic effect on AP decomposition, combustion performance, and mechanical properties in CSPs are also studied. The shapes of the prepared propellant samples are observed via scanning electron microscopy. The obtained Fc‐based BRCs have good redox performance, a positive effect on promoting AP decomposition, excellent combustion catalytic performance, and good mechanical properties. Meanwhile, they have a higher anti‐migration ability than catocene (Cat) and Fc. This study demonstrates that Fc‐terminated dendrimers have great potential to be applied as anti‐migration BRCs in CSPs.

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