Spinal cord injury (SCI) is a debilitating condition that can result in significant functional impairment and loss of quality of life. There is a growing interest in developing new therapies for SCI, and hydrogel-based multimodal therapeutic strategies have emerged as a promising approach. They offer several advantages for SCI repair, including biocompatibility, tunable mechanical properties, low immunogenicity, and the ability to deliver therapeutic agents. This article provides an overview of the recent advances in hydrogel-based therapy strategies for SCI repair, particularly within the past three years. We summarize the SCI hydrogels with varied characteristics such as phase-change hydrogels, self-healing hydrogel, oriented fibers hydrogel, and self-assembled microspheres hydrogel, as well as different functional hydrogels such as conductive hydrogels, stimuli-responsive hydrogels, adhesive hydrogel, antioxidant hydrogel, sustained-release hydrogel, etc. The composition, preparation, and therapeutic effect of these hydrogels are briefly discussed and comprehensively evaluated. In the end, the future development of hydrogels in SCI repair is prospected to inspire more researchers to invest in this promising field.

Ionic liquids (ILs) play a crucial role in the design of novel materials. The ionic nature of ILs provides numerous advantages in drug delivery, acting as a green solvent or active ingredient to enhance the solubility, permeability, and binding efficiency of drugs. They could also function as a structuring agent in the development of nano/micro particles for drug delivery, including micelles, vesicles, gels, emulsion, and more. This review summarize the ILs and IL-based gel structures with their advanced drug delivery applications. The first part of review focuses on the role of ILs in drug formulation and the applications of ILs in drug delivery. The second part of review offers a comprehensive overview of recent drug delivery applications of IL-based gel. It aims to offer new perspectives and attract more attention to open up new avenues in the biomedical applications of ILs and IL-based gels.

To design and evaluate a matrix metalloproteinase 9 (MMP-9)-responsive hydrogel for vital pulp therapy.
A peptide linker with optimized sensitivity toward MMP-9 was crosslinked with 4-arm poly (ethylene glycol)-norbornene (PEG-NB) by thiol-norbornene photo-polymerization. This resulted in the formation of a hydrogel network in which the peptide IDR-1002 was incorporated. Hydrogel characterization and gelation kinetics were examined with Fourier-transform infrared spectroscopy, scanning electron microscopy, rheological testing, and swelling evaluation. Hydrogel degradation was examined through multiple exposure to pre-activated MMP-9, to simulate flare-ups of dental pulp inflammation. The IDR-1002 released from degraded hydrogels was measured with high-performance liquid chromatography. Effect of IDR-1002 released from hydrogels on one-week-old multispecies oral biofilms was evaluated using confocal laser scanning microscopy.
MMP-9-responsive, injectable, and photo-crosslinkable hydrogels were successfully synthesized. When hydrogel degradation and release of IDR-1002 were examined with exposure to pre-activated MMP-9, IDR-1002 release was significantly correlated with elevated levels of MMP-9 (p < 0.05). The effectiveness of IDR-1002 in killing bacteria in multispecies oral biofilms was significantly enhanced when the hydrogels were immersed in 10 nM or 20 nM pre-activated MMP-9, compared to immersion in phosphate-buffered saline (p < 0.05).
The MMP-9-responsive hydrogel is a promising candidate for on-demand delivery of bioactive agent in vital pulp therapy.
MMP-9 is one of the most important diagnostic and prognostic biomarkers for pulpitis. An MMP-9-responsive hydrogel has potential to be used as an in-situ on-demand release system for the diagnosis and treatment of dental pulp inflammation.

Nanotechnology-enabled pesticide delivery systems have been widely studied and show great prospects in modern agriculture. Nanodelivery systems not only achieve the controlled release of agrochemicals but also possess many unique characteristics. This study presents the development of a pH-responsive pesticide nanoformulation utilizing hollow mesoporous silica nanoparticles (HMSNs) as a nanocarrier. The nanocarrier was loaded with the photosensitive pesticide prochloraz (Pro) and then combined with ZnO quantum dots (ZnO QDs) through electrostatic interactions. ZnO QDs serve as both the pH-responsive gatekeeper and the enhancer of the pesticide. The results demonstrate that the prepared nanopesticide exhibits high loading efficiency (24.96%) for Pro. Compared with Pro technical, the degradation rate of Pro loaded in HMSNs@Pro@ZnO QDs was reduced by 26.4% after 24 h ultraviolet (UV) exposure, indicating clearly improved photostability. In a weak acidic environment (pH 5.0), the accumulated release of the nanopesticide after 48 h was 2.67-fold higher than that in a neutral environment. This indicates the excellent pH-responsive characteristic of the nanopesticide. The tracking experiments revealed that HMSNs can be absorbed by rice leaves and subsequently transported to other tissues, indicating their potential for effective systemic distribution and targeted delivery. Furthermore, the bioactivity assays confirmed the fungicidal efficacy of the nanopesticide against rice blast disease. Therefore, the constructed nanopesticide holds great prospect in nanoenabled agriculture, offering a novel strategy to enhance pesticide utilization.

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Cancer has remained one of the leading causes of death worldwide, with a lack of effective treatment. The intrinsic shortcomings of conventional therapeutics regarding tumor specificity and non-specific toxicity prompt us to look for alternative therapeutics to mitigate these limitations. In this regard, we developed multifunctional bimetallic (FeCo) bi-MIL-88B-FC MOFs modified with folic acid-conjugated chitosan (FC) as drug delivery systems (DDS) for targeted delivery of 5-Fluorouracil (5-FU). The bi-MIL-88B nanocarriers were characterized through various techniques, including powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray, thermogravimetric analysis, and Fourier transform infrared spectroscopy. Interestingly, 5-FU@bi-MIL-88B-FC showed slower release of 5-FU due to a gated effect phenomenon endowed by FC surface coating compared to un-modified 5-FU@bi-MIL-88B. The pH-responsive drug release was observed, with 58% of the loaded 5-FU released in cancer cells mimicking pH (5.2) compared to only 24.9% released under physiological pH (5.4). The in vitro cytotoxicity and cellular internalization experiments revealed the superiority of 5-FU@bi-MIL-88B-FC as a highly potent targeted DDS against folate receptor (FR) positive SW480 cancer cells. Moreover, due to the presence of Fe and Co in the structure, bi-MIL-88B exhibited peroxidase-like activity for chemodynamic therapy. Based on the results, 5-FU@bi-MIL-88B-FC could serve as promising candidate for smart DDS by sustained drug release and selective targeting.

The complexity of the tumor microenvironment (TME) severely hinders the therapeutic effects of various cancer treatment modalities. The TME differs from normal tissues owing to the presence of hypoxia, low pH, and immune-suppressive characteristics. Modulation of the TME to reverse tumor growth equilibrium is considered an effective way to treat tumors. Recently, polymeric nanomedicines have been widely used in cancer therapy, because their synthesis can be controlled and they are highly modifiable, and have demonstrated great potential to remodel the TME. In this review, we outline the application of various stimuli responsive polymeric nanomedicines to modulate the TME, aiming to provide insights for the design of the next generation of polymeric nanomedicines and promote the development of polymeric nanomedicines for cancer therapy.

The chemotherapeutic drug of doxorubicin (DOX) has witnessed widespread applications for treating various cancers. DOX-treated dying cells bear cellular modifications which allow enhanced presentation of tumor antigen and neighboring dendritic cell activation. Furthermore, DOX also facilitate the immune-mediated clearance of tumor cells. However, disadvantages such as severe off-target toxicity, and prominent hydrophobicity have resulted in unsatisfactory clinical therapeutic outcomes. The effective delivery of DOX drug molecules is still challenging despite the rapid advances in nanotechnology and biomaterials. Huge progress has been witnessed in DOX nanoprodrugs owing to their brilliant benefits such as tumor stimuli-responsive drug release capacity, high drug loading efficiency and so on. This review summarized recent progresses of DOX prodrug-based nanomedicines to provide deep insights into future development and inspire researchers to explore DOX nanoprodrugs with real clinical applications.

Glutathione (GSH) consumption-enhanced cancer therapies represent important potential cancer treatment strategies. Herein, we developed a new multifunctional diselenide-crosslinked hydrogel with glutathione peroxidase (GPx)-like catalytic activity for GSH depletion-enhanced glucose oxidase (GOx)-mediated tumor starvation and hypoxia-activated chemotherapy. By increasing acid and H2O2 during GOx-induced tumor starvation, the degradation of the multiresponsive scaffold could be promoted, which led to accelerated release of the loaded drugs. Meanwhile, the overproduced H2O2 led to accelerated intracellular GSH consumption under the cascade catalysis of small molecular selenides released from the degraded hydrogel, further enhancing the curative effect of in situ H2O2 and subsequent multimodal cancer treatment. Following the GOx-induced amplification of hypoxia, tirapazamine (TPZ) was transformed into the highly toxic benzotriazinyl radical (BTZ·), exhibiting enhanced antitumor activity. This GSH depletion-augmented cancer treatment strategy effectively boosted GOx-mediated tumor starvation and activated the hypoxia drug, leading to significantly enhanced local anticancer efficacy. STATEMENT OF SIGNIFICANCE: There has been a growing interest in depleting intracellular GSH as a potential strategy for improving ROS-based cancer therapy. Herein, a bioresponsive diselenide-functionalized dextran-based hydrogel with GPx-like catalytic activity was developed for GSH consumption-enhanced local starvation- and hypoxia-activated melanoma therapy. Results showed that the overproduced H2O2 led to accelerated intracellular GSH consumption under the cascade catalysis of small molecular selenides released from the degraded hydrogel, further enhancing the curative effect of in situ H2O2 and subsequent multimodal cancer treatment.

Sustainable and precise fortification practices are necessary to ensure food security for the increasing human population. Precision agriculture aims to minimize the use of fertilizers and pesticides by developing smart materials for real-life agricultural practices. Here, we show that biomimetic mineralization can be efficiently employed to encapsulate and controllably release plant biostimulants (MiZax-3) to improve the quality and yield of capsicum (Capsicum annum) crops in field experiments. ZIF-8 encapsulation of MiZax-3 (MiZIFs) could significantly enhance its stability up to around 679 times (6p value = 0.0072) at field conditions. Our results demonstrate that the coordinating Zn ions and the MiZax-3 play a vital role in improving Zn content in the produced fruits by 2-fold, which is the first report of this nature on Zn content in fruits. We envision this platform as a starting point to investigate other biocompatible coordination-based platforms for micronutrient delivery in precision agriculture.