Wei Sun

Achieving persistent room-temperature phosphorescence (p-RTP), particularly those of tunable full-colors, from pure organic amorphous polymers is attractive but challenging. Particularly, those with tunable multicolor p-RTP in response to excitation wavelength and time are highly important but both fundamentally and technically underexplored. Here, a facile and general strategy toward color-tunable p-RTP from blue to orange-red based on amidation grafting of luminophores onto sodium alginate (SA) chains, resulting in amorphous polymers with distinct p-RTP and even impressively excitation-dependent and time-dependent afterglows is reported. p-RTP is associated with the unique semi-rigidified SA chains, effective hydrogen bonding network, and oxygen barrier properties of SA, whereas excitation-dependent and time-dependent afterglows should stem from the formation of diversified p-RTP emissive species with comparable but different lifetimes. These results outline a rational strategy toward amorphous smart luminophores with colorful, excitation-dependent, and time-dependent p-RTP, excellent solution processability, and film-forming ability for versatile applications.

Cancer metastasis is a serious concern and a major reason for treatment failure. Herein, we have reported the development of an effective and safe nanotherapeutic strategy that can eradicate primary tumors, inhibit metastasizing to lung, and control the metastasis and growth of distant tumors. Briefly, ferrimagnetic vortex-domain iron oxide nanoring (FVIO)-mediated mild magnetic hyperthermia caused calreticulin (CRT) expression on the 4T1 breast cancer cells. The CRT expression transmitted an “eat-me” signal and promoted phagocytic uptake of cancer cells by the immune system to induce an efficient immunogenic cell death, further leading to the macrophage polarization. This mild thermotherapy promoted 88% increase of CD8+ cytotoxic T lymphocyte infiltration in distant tumors and triggered immunotherapy by effectively sensitizing tumors to the PD-L1 checkpoint blockade. The percentage of CD8+ cytotoxic T lymphocytes can be further increased from 55.4% to 64.5% after combining with PD-L1 blockade. Moreover, the combination treatment also inhibited the immunosuppressive response of the tumor, evidenced by significant down-regulation of myeloid-derived suppressor cells (MDSCs). Our results revealed that the FVIO-mediated mild magnetic hyperthermia can activate the host immune systems and efficiently cooperate with PD-L1 blockade to inhibit the potential metastatic spreading as well as the growth of distant tumors.

This review focuses on the attachment of polymer brushes to polymeric biomaterial substrates by chemical surface modification methods for biomedical applications. In the first part of this paper, a general introduction to the synthesis of polymer brushes is given. Thereafter, a comprehensive overview of recent work on the chemical surface modification of polymeric biomaterials, with a focus on "grafting-to," "grafting-from," and "grafting-through" strategies, is provided. Finally, some representative cutting-edge biomedical applications of modified polymeric biomaterials, mainly including antifouling materials and biocompatible materials, are highlighted. On the basis of this literature study, a perspective on future trends in this field is provided.

Purpose: Osteosarcoma is the most common primary bone cancer and is notorious for pulmonary metastasis, representing a major threat to pediatric patients. An effective drug targeting osteosarcoma and its lung metastasis is urgently needed. Design: In this study, a sarcoma-targeting peptide-decorated disulfide-crosslinked polypeptide nanogel (STP-NG) was exploited for enhanced intracellular delivery of shikonin (SHK), an extract of a medicinal herb, to inhibit osteosarcoma progression with minimal systemic toxicity. Results: The targeted, loaded nanogel, STP-NG/SHK, killed osteosarcoma cells by inducing RIP1and RIP3-dependent necroptosis in vitro. Necroptosis is a novel cell death form that could be well adapted as an efficient antitumor strategy, the main obstacle of which is its high toxicity. After intravenous injection, STP-NG/SHK efficiently suppressed tumor growth and reduced pulmonary metastasis, offering greater tumor necrosis and higher RIP1 and RIP3 upregulation compared to free SHK or untargeted NG/SHK in vivo. Additionally, the treatment with NG/SHK or STP-NG/SHK showed minimal toxicity to normal organs, suggesting low systemic toxicity compared to free SHK. Conclusion: The STP-guided intracellular drug delivery system using the necroptosis mechanism showed profound anti-osteosarcoma activity, especially eliminated lung metastasis in vivo. This drug formulation may have great potential for treatment of osteosarcoma.