The nontargeted distribution and uncontrolled in vivo release of drugs impede their efficacy in the treatment of rheumatoid arthritis (RA). Delivering drugs to arthritic joints and releasing drugs on demand are a feasible solution to achieve the effective treatment of RA. In this paper, we report a facile method to assemble dual-stimuli responsive polymeric micelles from polyethylene glycol–phenylboric acid–triglycerol monostearate (PEG–PBA–TGMS, PPT) conjugates with the aim of delivering dexamethasone (Dex) to arthritic joints and controlling the release of Dex by inflammatory stimuli. We show that the release of Dex from the PPT micelles is accelerated in response to acidic pH and overexpressed matrix metalloproteinases. In an adjuvant-induced arthritis model, the PPT micelles preferentially accumulate in arthritic joints and show an excellent therapeutic efficacy after being intravenously administrated. Our results highlight the potential of the dual stimuli-responsive micelles as a promising therapeutic option for the effective treatment of inflammatory diseases.
Flame-retarded epoxy thermosets are highly desirable for electronics-related basic materials in the new-generation information applications. Herein, a DOPO-anchored benzothiadiazole flame retardant, namely DOPO-BTD , is designed and synthesized for P/N/S synergistic flame-retarded epoxy thermosets. DOPO-BTD possesses good thermal stability and excellent compatibility with the epoxy matrix. As reflected by UL 94 test, the DOPO-BTD coated EP passes the V0 rating and achieves a higher LOI value of 34.6% at ultralow P content of 0.39 wt%. The investigation of the DOPO-BTD -triggered P/N/S synergistic flame-retarded effect by thermal images further validated the flame retarded efficacy and dramatic inhibition of the flame. Meanwhile, the incorporation of 4.8 wt% DOPO-BTD into the epoxy matrix, the PHRR, THR, SPR, TSP, and COP are significantly decreased by 37.97%, 27.44%, 25.49%, 19.83%, and 31.70%, respectively. Additionally, the fire growth index (FGI) is sharply dropped 26.06%. Moreover, the TGIR and TGMS results convince the flame-retarded mechanism of DOPO-BTD through the combination of the gas-phase and condensed-phase pathways. The P/N/S synergistic DOPO-BTD can serve as a promising flame retardant for efficiently fabricating the flame-retarded epoxy thermosets, and this study sheds light on the development of multiple elements synergistic flame-retardants for functional polymers with great application potential.
危险品化学品经营许可证（带存储）