Editorial: Biodegradable polymers for biomedical applications - Volume IV

Biodegradable polymers have revolutionized the biomedical landscape, evolving from bioinert structural supports into highly dynamic, responsive, and functionalized biomaterials. Volume IV of the Research Topic Biodegradable Polymers for Biomedical Applications compiles ten exemplary contributions-comprising five original research articles and five comprehensive reviews-that collectively highlight the cutting-edge innovations in this field. These works, which have already garnered significant academic attention, explore the intricate synthesis, characterization, and clinical translation of polymeric systems designed to address unmet needs in tissue regeneration, targeted pharmacokinetics, and implantable medical devices.A prominent theme in this volume is the engineering of microenvironments to guide cellular behavior and tissue repair. For delicate tissues like the cornea, Pi et al. developed a multifunctional hydrogel utilizing dynamic cross-linking between quaternary ammonium chitosan (QCS) and tannic acid (TA). This system not only provides robust adhesion to wet mucosal surfaces but also actively scavenges reactive oxygen species (ROS), shifting the wound microenvironment from a fibrotic to a regenerative state and preserving optical transparency (Pi et al., 2026).In the realm of cutaneous wound healing, Wei et al. demonstrated the profound efficacy of a thermosensitive polyethylene glycol-polyester (PLGA-PEG-PLGA) hydrogel. By serving as a sustained-release depot for mesenchymal stem cell-derived exosomes, this platform synergistically promotes angiogenesis, accelerates myofibroblast differentiation, and modulates inflammatory responses, overcoming the rapid clearance that typically plagues topical biologic delivery (Wei et al., 2025).Addressing musculoskeletal and neural challenges, Wang et al. comprehensively reviewed the utilization of hyaluronic acid hydrogels in meniscus repair, emphasizing their biomimetic viscoelasticity, ability to facilitate cell migration, and chondro-protective properties via CD44 receptor interaction (Wang et al., 2025). Concurrently, Feng et al. introduced a novel polylactic acid (PLA) and silk fibroin (SF) composite electrospun fiber membrane. The precise nanopore structure and fiber alignment of this scaffold provided essential contact guidance and structural support, significantly enhancing the growth behavior of peripheral nerve cells for bridging severe nerve defects (Feng et al., 2025).The volume also underscores the transformative role of biodegradable polymers in modern pharmacokinetics. In oncology, Ma et al. tackled the poor water solubility of the natural antineoplastic compound -oryzanol by encapsulating it within PLGA nanoparticles. These nanocarriers effectively leveraged their uniform spherical morphology (approximately 241 nm) to enhance cellular internalization, successfully amplifying apoptotic cascades against breast cancer cells while minimizing systemic off-target toxicity (Ma et al., 2025).For clinical pain management, Guo et al. reviewed the paradigm shift toward natural polymerssuch as chitosan and alginate-for delivering local anesthetics. These biodegradable matrices mitigate the burst-release toxicity of traditional liposomal carriers, extending the duration of analgesia via targeted, mucoadhesive zero-order release profiles (Guo et al., 2026).Metabolic and degenerative diseases were similarly addressed. Ghazwani et al. evaluated the potential of natural polymers in shielding insulin from enzymatic degradation in the gastrointestinal tract, facilitating both sustained and non-invasive delivery modalities crucial for improving patient compliance in diabetes management (Ghazwani et al., 2025). In the context of knee osteoarthritis, Zhang et al. summarized how polymeric intra-articular delivery systems (utilizing PLA, PLGA, and PEG) ensure high localized drug concentrations, effectively halting cartilage loss and subduing synovial inflammation while circumventing systemic side effects (Zhang et al., 2025).Beyond drug delivery and soft hydrogels, structural implants are undergoing significant biochemical refinement. Hu et al. presented a groundbreaking approach to urological implants with a novel gradient-degradable ureteral stent. Constructed from copolymers of trimethylene carbonate (TMC) and glycolic acid (GA) using a multilayer impregnation technique, this stent degrades progressively via enzymatic erosion (Hu et al., 2026). This gradient architecture successfully maintains luminal patency and physiological urinary pH, preventing the catastrophic obstructive fragmentation typical of bulk-degrading synthetic stents (Hu et al., 2026).Finally, Li et al. reviewed the critical physiological barrier of avascularity in subcutaneous transplantation-a preferred, minimally invasive site for engineered tissues and islet cell grafts. Their analysis highlighted how polymer-based delivery of angiogenic factors (such as basic fibroblast growth factor) can pre-vascularize the subcutaneous niche, dramatically improving the survival, engraftment, and endocrine function of subsequent cellular transplants (Li et al., 2025).The diverse methodologies and clinical targets of the ten papers featured in this volume are summarized below, illustrating the breadth of current biodegradable polymer research (Table 1). Volume IV of this Research Topic provides a comprehensive cross-section of the state-of-the-art in biodegradable biomaterials. By seamlessly integrating the mechanical predictability of synthetic polymers with the intrinsic bioactivity of natural alternatives, the researchers in this collection are paving the way for the next generation of precision therapeutics and regenerative implants. The continued convergence of material science, nanotechnology, and stem cell biology will undoubtedly transition these experimental paradigms into standard clinical care.