Yunnan Baiyao-loaded multifunctional microneedle patches for rapid hemostasis and cutaneous wound healing

Research Progress on Antibacterial Applications of Bioactive Materials in Wound Infections: Design, Challenges, and Prospects

Bacterial wound infections pose a significant threat to global health, exacerbated by the increase in multidrug-resistant bacteria (MDRB) and the formation of elastic biofilms. This review explores the transformative potential of bioactive materials in addressing these challenges, focusing on their design, mechanisms of action, and therapeutic effects. In vivo, bioactive materials are designed to respond to unique bacterial microenvironment (BME), utilizing enzyme activity, controlled gas release, surface functionalization, and immune regulation to combat infections. In vitro, this review provides a comprehensive overview of the latest advances in the rational design of these materials, emphasizing the synergistic integration of structural modifications (such as size and morphology) with external physical stimuli (such as light, sound, electricity, magnetism, and force) to enhance antibacterial performance. Finally, the outstanding challenges and prospects in this rapidly evolving field are discussed.

Formulation, development and in vivo characterization of selegiline hydrochloride nanostructured lipid nanocarrier loaded microneedle array patch for depression

Depression is a common mental condition causing depressed mood and loss of pleasure. The primary treatment approach for the management of depression consists of the use of selegiline (MAO-B) inhibitor compound. The present work aimed to develop and optimize selegiline-loaded nanostructured lipid carriers for transdermal application, utilizing a 23 full factorial design approach. The optimized nanostructured lipid carriers formulation (Batch B7) demonstrated a particle size of 158.71 ± 0.56 nm, a narrow size distribution (0.266 ± 0.006), high entrapment efficiency (59.60 ± 0.34 %), and a zeta potential of -23.2 ± 2.21 mV. Furthermore, x-ray diffraction and differential scanning calorimetry studies revealed the amorphous transformation of selegiline within the nanostructured lipid carrier. Transmission Electron Microscopy study has shown that nanostructured lipid carrier particles had a spherical shape with a smooth surface. These optimized nanostructured lipid carriers were then incorporated into a microneedle array patch for transdermal delivery. The selegiline-loaded nanostructured lipid carrier microneedle array patch exhibited no skin irritation in a rabbit model. It enhanced drug diffusion ex vivo (1.13-fold compared to pure selegiline-loaded microneedle array patch) with 90 % drug release in 12 h. The pharmacokinetic study demonstrated a steady and controlled release profile with a half-life of 29.9 ± 0.14 h and AUC0-t (26.57 ± 0.51 μg/ml*h) of selegiline loaded nanostructured lipid carrier microneedle array patch. On the contrary, a pure selegiline-loaded microneedle array patch showed a short half-life of 6.5 ± 0.26 h and AUC0-t (20.90 ± 0.31 μg/ml*h). The sustained release profile and prolonged half-life in plasma and the brain suggest improved therapeutic efficacy. Histopathology analysis revealed no significant toxicity to vital organs. Thus, a selegiline nanostructured lipid carrier-loaded microneedle array patch can increase brain bioavailability compared to a pure selegiline-loaded microneedle array patch for managing depression.

Application trends of hydrogen-generating nanomaterials for the treatment of ROS-related diseases

Reactive oxygen species (ROS) play essential roles in both physiological and pathological processes. Under physiological conditions, appropriate amounts of ROS play an important role in signaling and regulation in cells. However, too much ROS can lead to many health problems, including inflammation, cancer, delayed wound healing, neurodegenerative diseases (such as Parkinson's disease and Alzheimer's disease), and autoimmune diseases, and oxidative stress from excess ROS is also one of the most critical factors in the pathogenesis of cardiovascular and metabolic diseases such as atherosclerosis. Hydrogen gas effectively removes ROS from the body due to its good antioxidant properties, and hydrogen therapy has become a promising gas therapy strategy due to its inherent safety and stability. The combination of nanomaterials can achieve targeted delivery and effective accumulation of hydrogen, and has some ameliorating effects on diseases. Herein, we summarize the use of hydrogen-producing nanomaterials for the treatment of ROS-related diseases and talk about the prospects for the treatment of other ROS-induced disease models, such as acute kidney injury.

A dissolving microneedle patch loaded with plumbagin/hydroxypropyl-β-cyclodextrin inclusion complex for infected wound healing

Treating infected wounds is facing a serious challenge due to the rapid spread of antibiotic resistance worldwide. In the search for novel antimicrobial drugs, natural products often serve as a crucial resource. Plumbagin (PLB) is the most important natural active ingredient in the root of Plumbago zeylanica L. known for its excellent antibacterial ability. However, the application of PLB is limited because of its poor water solubility, instability, and tendency to sublimate. In this study, we propose a solution by designing a hyaluronic acid (HA)/polyvinylpyrrolidone (PVP) dissolving microneedle patch loaded with PLB/hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex. PLB was encapsulated into the cavity of HP-β-CD to improve its solubility and stability using the neutralization agitation method. The formation of the inclusion complex significantly increased the water solubility of PLB to 1350 ± 6.8 μg/mL, which is 17 times higher than its original value of 79.3 ± 1.7 μg/mL. The encapsulation efficiency was found to be 94.82 ± 3.34 %. In vitro drug release studies, PLB microneedles loaded with PLB/HP-β-CD inclusion complex rapidly released into PBS within 15 min. Furthermore, the PLB microneedles exhibited strong antibacterial activity against Staphylococcus aureus (S. aureus) both in vivo and in vitro. They also remarkably accelerated the healing of infected wounds in mice by enhancing collagen deposition and re-epithelialization, reducing inflammation, and stimulating angiogenesis. Overall, this multifunctional microneedle patch shows promising potential for clinical applications in the healing of infected wounds.

Hispidulin-rich fraction of Clerodendrum fragrans Wild. (Sesewanua) dissolving microneedle as antithrombosis candidate: A proof of concept study

Existing conventional antithrombosis drugs have caused many side effects, opening up opportunities for the development of new thrombotic drugs. There is potential to use the hispidulin-rich fraction of sesewanua (HRFS) as a new antithrombotic. The oral route limitation of hispidulin, as a low water solubility and non-polar compound, can be addressed. This study explores the potential of HRFS in the form of dissolving microneedles (DMN). The formula was created using polymers such as polyvinyl alcohol (PVA), polyvinyl pyrrolidone K-30 (PVP), and non-ionic surfactant. Ex vivo permeation studies found that 184.95 µg/cm2 of hispidulin was released 60 h after the best formulation. After 14 days of applying HRFS-DMN, the anticoagulant and antioxidant activity in male albino rats showed higher Activated Partial Thromboplastin Time (aPTT) and Prothrombin Time (PT) values and lower Inter Cellular Adhesion Molecule-1 (ICAM-1) values. No statistically significant differences were found between the effects of two and four HRFS-DMN and the injection of heparin at a dosage of 200 IU per kilogram. However, notable distinctions were observed when comparing HRFS-DMN to negative controls, oral and quercetin as positive controls at anti-ICAM activity. The findings confirmed the feasibility of HRFS-DMN for thrombosis and its effectiveness in delivering Hispidulin (HIS) into the bloodstream. This DMN is non-irritating, safe, and painless, showing promising outcomes in enhancing the efficacy of thrombosis treatment via the transdermal route.

Smart drug delivery and responsive microneedles for wound healing

Wound healing is an ongoing concern for the medical community. The limitations of traditional dressings are being addressed by materials and manufacturing technology. Microneedles (MNs) are a novel type of drug delivery system that has been widely used in cancer therapy, dermatological treatment, and insulin and vaccine delivery. MNs locally penetrate necrotic tissue, eschar, biofilm and epidermis into deep tissues, avoiding the possibility of drug dilution and degradation and greatly improving administration efficiency with less pain. MNs represent a new direction for wound treatment and transdermal delivery. In this study, we summarise the skin wound healing process and the mechanical stimulation of MNs in the context of the wound healing process. We also introduce the structural design and manufacture of MNs. Subsequently, MNs are categorised according to the loaded drugs, where the design of the MNs according to the traumatic biological/biochemical microenvironment (pH, glucose, and bacteria) and the physical microenvironment (temperature, light, and ultrasound) is emphasised. Finally, the advantages of MNs are compared with traditional drug delivery systems and their prospects are discussed.

Composite microneedles loaded with Astragalus membranaceus polysaccharide nanoparticles promote wound healing by curbing the ROS/NF-κB pathway to regulate macrophage polarization

The healing of chronic diabetic wounds remains a formidable challenge in modern times. In this study, a novel traditional Chinese medicine microneedle patch was designed based on the physiological characteristics of wounds, with properties including hemostasis, anti-inflammatory, antioxidant, antimicrobial, and induction of angiogenesis. Initially, white peony polysaccharide (BSP) with hemostatic properties and carboxymethyl chitosan (CMCS) with antimicrobial capabilities were used as materials for microneedle fabrication. To endow it with antimicrobial, procoagulant, and adhesive properties. Among them, loaded with ROS-sensitive nanoparticles of Astragalus polysaccharides (APS) based on effective components baicalein (Bai) and berberine (Ber) from Scutellaria baicalensis (SB) and Coptis chinensis (CC) drugs (APB@Ber). Together, they are constructed into multifunctional traditional Chinese medicine composite microneedles (C/B@APB@Ber). Bai and Ber synergistically exert anti-inflammatory and antimicrobial effects. Microneedle patches loaded with BSP and APS exhibited significant effects on cell proliferation and angiogenesis induction. The combination of composite polysaccharides enabled the microneedles to adhere stably to wounds and provide sufficient strength to penetrate the biofilm and induce dispersion. The combination of composite polysaccharides enabled the microneedles to adhere stably to wounds and provide sufficient strength to penetrate the biofilm and induce dispersion. Therefore, traditional Chinese medicine multifunctional microneedle patches offer potential medical value in promoting the healing of diabetic wounds.

Visualizing the transdermal delivery of berberine loaded within chitosan microneedles using mass spectrometry imaging

Berberine (BR), an alkaloid isolated from the Chinese traditional medicine Coptidis rhizoma, exhibits therapeutic effects on several diseases including bacterial infections, diabetes, and hyperlipidemia, but the oral availability is poor. In this work, we prepared the chitosan microneedle array-loaded BR (BR-CS MNAs) to transdermally deliver BR, and the spatial distribution of BR in heterogeneous skin tissues was analyzed and imaged by matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI). Some endogenous phospholipids with specific spatial distribution were used to differentiate the epidermis and dermis regions of the skin. The results showed that BR was effectively delivered and could permeate to both epidermis and dermis regions of the skin. This demonstrated the feasibility of MALDI-MSI to evaluate the transdermal delivery efficiency of microneedle arrays and suggested BR could be transdermally delivered by CS MNAs.

Microneedle patches incorporating zinc-doped mesoporous silica nanoparticles loaded with betamethasone dipropionate for psoriasis treatment

Treating psoriasis presents a major clinical challenge because of the limitations associated with traditional topical glucocorticoid therapy. This study introduced a drug delivery system utilizing zinc-doped mesoporous silica nanoparticle (Zn-MSN) and microneedle (MN), designed to enhance drug utilization for prolonged anti-inflammatory and anti-itch effects. The MN system facilitated the transdermal delivery of betamethasone dipropionate (BD), allowing its slow release. The BD@Zn-MSN-MN system promoted the polarization of macrophages towards the anti-inflammatory M2 phenotype, achieving superior anti-inflammatory effects compared to the clinically used BD cream. Additionally, this study demonstrated that BD@Zn-MSN-MN could further alleviate itching in psoriasis-afflicted mice by decreasing the excitability of the transient receptor potential vanilloid V1 (TRPV1) ion channel positive neurons and reducing the release of calcitonin gene-related peptide (CGRP) in the dorsal root ganglion (DRG). These findings offer new insights and effective therapeutic options for the future design of transdermal drug delivery for psoriasis.

Living photosynthetic microneedle patches for in situ oxygenation and postsurgical melanoma therapy

Surgical excision remains the principal treatment for melanoma, while tumor recurrence and delayed wound healing often occur due to the residual tumor cells and hypoxic microenvironment in the postoperative skin wounds. Herein, we present a living photosynthetic microneedle (MN) patch (namely MA/CM@MN) loaded with microalgae (MA) and cuttlefish melanin (CM) for postsurgical melanoma therapy and skin wound healing. Benefiting from the oxygenic photosynthesis of the alive MA in the MN base, the MA/CM@MN can generate oxygen under light exposure, thus facilitating skin cell proliferation and protecting cells against hypoxia-induced cell death. In addition, with CM nanoparticles embedded in the MN tips, the MA/CM@MN can be effectively heated up under near-infrared (NIR) irradiation, contributing to a strong tumor killing efficacy on melanoma cells in vitro. Further experiments demonstrate that the NIR-irradiated MA/CM@MN effectively prevents local tumor recurrence and simultaneously promotes the healing of tumor-induced wounds after incomplete tumor resection in melanoma-bearing mice, probably because the MA/CM@MN can inhibit tumor cell proliferation, stimulate tumor cell apoptosis, and mitigate tissue hypoxia in light. These results indicate that the living photosynthetic MN patch offers an effective therapeutic strategy for postoperative cancer therapy and wound healing applications.

A separable double-layer self-pumping dressing containing astragaloside for promoting wound healing

Some skin wounds often have many exudate. Ordinary single layer electrospunning nanofiber wound dressings often don't have enough capacity to absorb them. Therefore, a separable double layer electrospunning nanofiber dressing was developed in this work. The dressing had a separable feature that allowed the upper layer to be separated and removed after it had absorbed a significant amount of wound exudate. This dressing consisted of an upper layer of super hydrophilic sodium polyacrylate nanofibers and a bottom layer of 3D-structure coaxial nanofibers with encapsulated Astragaloside (AS). The results showed that nanofibers had better morphology. The water absorption rate, water vapor transmission rate and free radical scavenging rate of the double-layer dressings were 1461.71 ± 39.72 %, 1193.63 ± 134 g·m-2·day-1, and 63.35 ± 3.65 %, respectively. The double-layer nanofiber dressing achieved 65.69 ± 2.62 % and 75.10 ± 6.26 % inhibition against Staphylococcus aureus and Escherichia coli, respectively. The double-layer dressing had proliferative, migratory, and adhesive effects on L929 fibroblasts. And the double-layer dressing resulted in a 96.78 ± 1.0 % wound healing rate in rats after giving a 14 days treatment. Therefore, the 3D-structure separable double-layer wound dressing designed and prepared in this study was effective in promoting wound healing.

Multifunctional Microneedle Patch with Diphlorethohydroxycarmalol for Potential Wound Dressing

BACKGROUND

Treatment of skin wounds with diverse pathological characteristics presents significant challenges due to the limited specific and efficacy of current wound healing approaches. Microneedle (MN) patches incorporating bioactive and stimulus materials have emerged as a promising strategy to overcome these limitations and integrating bioactive materials with anti-bacterial and anti-inflammatory properties for advanced wound dressing.

METHODS

We isolated diphlorethohydroxycarmalol (DPHC) from Ishige okamurae and assessed its anti-inflammatory and anti-bacterial effects on macrophages and its antibacterial activity against Cutibacterium acnes. Subsequently, we fabricated polylactic acid (PLA) MN patches containing DPHC at various concentrations (0-0.3%) (PDPHC MN patches) and evaluated their mechanical properties and biological effects using in vitro and in vivo models.

RESUTLS

Our findings demonstrated that DPHC effectively inhibited nitric oxide production in macrophages and exhibited rapid bactericidal activity against C. acnes. The PDPHC MN patches displayed potent antibacterial effects without cytotoxicity. Moreover, in 2,4-Dinitrochlorobenzene-stimulated mouse model, the PDPHC MN patches significantly suppressed inflammatory response and cutaneous lichenification.

CONCLUSION

The results suggest that the PDPHC MN patches holds promise as a multifunctional wound dressing for skin tissue engineering, offering antibacterial properties and anti-inflammatory properties to promote wound healing process.

Microneedle transdermal drug delivery as a candidate for the treatment of gouty arthritis: Material structure, design strategies and prospects

Gouty arthritis (GA) is caused by monosodium urate (MSU) crystals deposition. GA is difficult to cure because of its complex disease mechanism and the tendency to reoccur. GA patients require long-term uric acid-lowering and anti-inflammatory treatments. In the past ten years, as a painless, convenient and well-tolerated new drug transdermal delivery method, microneedles (MNs) administration has been continuously developed, which can realize various drug release modes to deal with various complex diseases. Compared with the traditional administration methods (oral and injection), MNs are more conducive to the long-term independent treatment of GA patients because of their safe, efficient and controllable drug delivery ability. In this review, the pathological mechanism of GA and common therapeutic drugs for GA are summarized. After that, MNs drug delivery mechanisms were summarized: dissolution release mechanism, swelling release mechanism and channel-assisted release mechanism. According to drug delivery patterns of MNs, the mechanisms and applications of rapid-release MNs, long-acting MNs, intelligent-release MNs and multiple-release MNs were reviewed. Additionally, existing problems and future trends of MNs in the treatment of GA were also discussed. STATEMENT OF SIGNIFICANCE: Gout is an arthritis caused by metabolic disease "hyperuricemia". Epidemiological studies show that the number of gouty patients is increasing rapidly worldwide. Due to the complex disease mechanism and recurrent nature of gout, gouty patients require long-term therapy. However, traditional drug delivery modes (oral and injectable) have poor adherence, low drug utilization, and lack of local localized targeting. They may lead to adverse effects such as rashes and gastrointestinal reactions. As a painless, convenient and well-tolerated new drug transdermal delivery method, microneedles have been continuously developed, which can realize various drug release modes to deal with gouty arthritis. In this review, the material structure, design strategy and future outlook of microneedles for treating gouty arthritis will be reviewed.

Polysaccharide hydrogels for skin wound healing

Advances in the development and utilization of polysaccharide materials are highly promising, offering prominent applications in the field of tissue engineering for addressing diverse clinical needs, including wound healing, bone regeneration, cartilage repair, and treatment of conditions such as arthritis. Novel polysaccharide materials are popular owing to their inherent stability, biocompatibility, and repeatability. This review presents an overview of the biomedical applications of natural polysaccharide hydrogels and their derivatives. Herein, we discuss the latest advancements in the fabrication, physicochemical properties, and biomedical applications of polysaccharide-based hydrogels, including chitosan, hyaluronic acid, alginate, and cellulose. Various processing techniques applicable to polysaccharide materials are explored, such as the transformation of polysaccharide hydrogels into electrospun nanofibers, microneedles, microspheres, and nanogels. Furthermore, the use of polysaccharide hydrogels in the context of wound-healing applications, including hemostatic effects, antimicrobial activities, anti-inflammatory properties, and promotion of angiogenesis, is presented. Finally, we address the challenges encountered in the development of polysaccharide hydrogels and outline the potential prospects in this evolving field.

Dencichine/palygorskite nanocomposite incorporated chitosan/polyvinylpyrrolidone film for accelerating wound hemostasis

The development of efficient, safe, environmentally friendly, and user-friendly hemostatic dressings remains a great challenge for researchers. A variety of clay minerals and plant extracts have garnered considerable attention due to their outstanding hemostatic efficacy and favorable biosafety. In this study, a facile solution casting strategy was employed to prepare nanocomposite films by incorporating natural nanorod-like palygorskite (Pal) and herb-derived hemostat dencichine (DC) based on chitosan and polyvinylpyrrolidone. The dynamic blood clotting index demonstrated that the nanocomposite film with a DC addition of 1.0 wt% exhibited significantly superior hemostatic properties compared to both pure DC powder or commercial hemostatic agent Yunnan Baiyao. This improvement was primarily attributed to proper blood affinity, increased porosity, enhanced adhesion of platelets and erythrocytes, as well as the accelerated activation of coagulation factors and platelets. Under the synergistic effect of Pal and DC, the nanocomposite film displayed suitable tensile strength (20.58 MPa) and elongation at break (47.29 %), which may be due to the strong intermolecular hydrogen bonding and electrostatic interaction between Pal/DC and macropolymers. Notably, the nanocomposite film exhibited remarkable antibacterial effectiveness and desirable cytocompatibility, as well as the capability of promoting wound healing in vitro. Taken together, the nanocomposite film synergized with Pal and DC is expected to be an efficacious and suitable wound dressing.

A flexible and dissolving traditional Chinese medicine microneedle patch for sleep-aid intervention

About a quarter of the world's population suffers from insomnia, and the number of the insomniacs is gradually increasing. However, the current drug therapy and non-drug therapy sleep-aid methods have certain limitations. In general, the sleep-aid effect of drug therapy is better than that of Non-drug therapy, but western medicine may lead to some side effects and drug abuse. Although the side effects of Chinese Herbal Medicine (CHM) are relatively small, making the herbal decoction is complex and time-consuming. Therefore, exploring a novel sleep-aid method is very significant. In this paper, a flexible and dissolving Traditional Chinese Medicine (TCM) microneedle patch is proposed for sleep-aid intervention. The TCM microneedle patch is a micrometer-scale intrusive object, and the herbal extracts are carried by the patch. The materials, design method, and fabrication process of the microneedle patch have been described in detail. Besides, the mechanical characteristics of the microneedle patch, sleep-aid effect evaluation method, and experimental scheme have been presented. Three microneedle tips with radii of 5 μm, 15 μm, and 22 μm are selected for simulation analysis. Abaqus simulation results indicate that the smaller the radius of the microneedle tip, the smaller the piercing force. Considering that the microneedle should easily penetrate the skin without buckling, that is, the piercing force should be larger than the buckling force, thus 15 μm, instead of 5 μm or 22 μm, is more suitable to be adopted as the radius of the microneedle tip. For the microneedle with the radius of 15 μm, the piercing force is 0.033 N, and the difference between the piercing force and buckling force is 0.036 N. Experimental results demonstrate that the fracture force of the microneedle is about 0.29 N, which is far larger than the piercing force and buckling force. The single-lead EEG signals of the frontal lobe are used to evaluate the sleep-aid effect of the TCM microneedle patch. After sleep-aid intervention on the Anmian and Yintang acupoints using the patches, for most subjects, the ratios of the low-frequency brain wave energies to the high-frequency brain wave energies are increased obviously, indicating that the proposed sleep-aid method is effective.

Targeting Diverse Wounds and Scars: Recent Innovative Bio-design of Microneedle Patch for Comprehensive Management

Wounds and the subsequent formation of scars constitute a unified and complex phased process. Effective treatment is crucial; however, the diverse therapeutic approaches for different wounds and scars, as well as varying treatment needs at different stages, present significant challenges in selecting appropriate interventions. Microneedle patch (MNP), as a novel minimally invasive transdermal drug delivery system, has the potential for integrated and programmed treatment of various diseases and has shown promising applications in different types of wounds and scars. In this comprehensive review, the latest applications and biotechnological innovations of MNPs in these fields are thoroughly explored, summarizing their powerful abilities to accelerate healing, inhibit scar formation, and manage related symptoms. Moreover, potential applications in various scenarios are discussed. Additionally, the side effects, manufacturing processes, and material selection to explore the clinical translational potential are investigated. This groundwork can provide a theoretical basis and serve as a catalyst for future innovations in the pursuit of favorable therapeutic options for skin tissue regeneration.

Application of hydrogel microneedles in the oral cavity

Microneedles are a transdermal drug delivery system in which the needle punctures the epithelium to deliver the drug directly to deep tissues, thus avoiding the influence of the first-pass effect of the gastrointestinal tract and minimizing the likelihood of pain induction. Hydrogel microneedles are microneedles prepared from hydrogels that have good biocompatibility, controllable mechanical properties, and controllable drug release and can be modified to achieve environmental control of drug release in vivo. The large epithelial tissue in the oral cavity is an ideal site for drug delivery via microneedles. Hydrogel microneedles can overcome mucosal hindrances to delivering drugs to deep tissues; this prevents humidity and a highly dynamic environment in the oral cavity from influencing the efficacy of the drugs and enables them to obtain better therapeutic effects. This article analyzes the materials and advantages of common hydrogel microneedles and reviews the application of hydrogel microneedles in the oral cavity.

Preparation and Application of Hemostatic Hydrogels

Hemorrhage remains a critical challenge in various medical settings, necessitating the development of advanced hemostatic materials. Hemostatic hydrogels have emerged as promising solutions to address uncontrolled bleeding due to their unique properties, including biocompatibility, tunable physical characteristics, and exceptional hemostatic capabilities. In this review, a comprehensive overview of the preparation and biomedical applications of hemostatic hydrogels is provided. Particularly, hemostatic hydrogels with various materials and forms are introduced. Additionally, the applications of hemostatic hydrogels in trauma management, surgical procedures, wound care, etc. are summarized. Finally, the limitations and future prospects of hemostatic hydrogels are discussed and evaluated. This review aims to highlight the biomedical applications of hydrogels in hemorrhage management and offer insights into the development of clinically relevant hemostatic materials.

Applications and prospects of microneedles in tumor drug delivery

As drug delivery devices, microneedles are used widely in the local administration of various drugs. Such drug-loaded microneedles are minimally invasive, almost painless, and have high drug delivery efficiency. In recent decades, with advancements in microneedle technology, an increasing number of adaptive, engineered, and intelligent microneedles have been designed to meet increasing clinical needs. This article summarizes the types, preparation materials, and preparation methods of microneedles, as well as the latest research progress in the application of microneedles in tumor drug delivery. This article also discusses the current challenges and improvement strategies in the use of microneedles for tumor drug delivery.

Exploration of the anti-inflammatory, analgesic, and wound healing activities of Bletilla Striata polysaccharide

Bletilla Striata (BS) Polysaccharide (BSP) is one of the main components of the traditional Chinese medicinal plant Bletilla striata Rchb. F. BSP has been widely used in antimicrobial and hemostasis treatments in clinics. Despite its use in skin disease treatment and cosmetology, the effects of BSP on wound healing remain unclear. Here we investigated the anti-inflammatory, antioxidant, and analgesic effects of BSP and explored its impact on morphological changes and inflammatory mediators during wound healing. A carrageenan-induced mouse paw edema model was established to evaluate the anti-inflammatory effect of BSP. Antioxidant indicators, including NO, SOD, and MDA, were measured in the blood and liver. The increased pain threshold induced by BSP was also determined using the hot plate test. A mouse excisional wound model was applied to evaluate the wound healing rate, and HE staining and Masson staining were used to detect tissue structure changes. In addition, ELISA was employed to detect the expression of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β in serum. BSP significantly decreased the concentration of NO and MDA in serum and liver while increasing SOD activity. It exhibited a notable improvement in mouse paw edema induced by carrageenan. BSP dose-dependently delayed the appearance of licking behavior in mice, indicating its analgesic effect. Compared to the control group, the wound healing rate was significantly improved in the BSP treatment group. HE and Masson staining results showed that the BSP and 'Jingwanhong' ointment groups had slightly milder inflammatory responses and significantly promoted more new granulation tissue formation. The levels of serum inflammatory mediators TNF-α, IL-1β, and IL-6 were reduced to varying degrees. The results demonstrated that BSP possesses anti-inflammatory, antioxidant, analgesic, and wound healing properties, and it may promote wound healing through inhibition of inflammatory cytokine synthesis and release.

Exploration of the Delivery of Oncolytic Newcastle Disease Virus by Gelatin Methacryloyl Microneedles

Oncolytic Newcastle disease virus is a new type of cancer immunotherapy drug. This paper proposes a scheme for delivering oncolytic viruses using hydrogel microneedles. Gelatin methacryloyl (GelMA) was synthesized by chemical grafting, and GelMA microneedles encapsulating oncolytic Newcastle disease virus (NDV) were prepared by micro-molding and photocrosslinking. The release and expression of NDV were tested by immunofluorescence and hemagglutination experiments. The experiments proved that GelMA was successfully synthesized and had hydrogel characteristics. NDV was evenly dispersed in the allantoic fluid without agglomeration, showing a characteristic virus morphology. NDV particle size was 257.4 ± 1.4 nm, zeta potential was -13.8 ± 0.5 mV, virus titer TCID50 was 107.5/mL, and PFU was 2 × 107/mL, which had a selective killing effect on human liver cancer cells in a dose and time-dependent manner. The NDV@GelMA microneedles were arranged in an orderly cone array, with uniform height and complete needle shape. The distribution of virus-like particles was observed on the surface. GelMA microneedles could successfully penetrate 5% agarose gel and nude mouse skin. Optimal preparation conditions were freeze-drying. We successfully prepared GelMA hydrogel microneedles containing NDV, which could effectively encapsulate NDV but did not detect the release of NDV.

Novel microneedle platforms for the treatment of wounds by drug delivery: A review

The management and treatment of wounds are complex and pose a substantial financial burden to the patient. However, the complex environment of wounds leads to inadequate drug absorption to achieve the desired therapeutic effect. As a novel technological platform, microneedles are widely used in drug delivery because of their multiple drug loading, multistage drug release, and multiple designs of topology. This study systematically summarizes and analyzes the manufacturing methods and limitations of different microneedles, as well as the latest research advances in pain management, drug delivery, and healing promotion, and presents the challenges and opportunities for clinical applications. On this basis, the development of microneedles in external wound repair and management is envisioned, and it is hoped that this study can provide guidelines for the design of microneedle systems in different application contexts, including the selection of materials, preparation methods, and structural design, to achieve better healing and regeneration results.

Dual properties of pharmacological activities and preparation excipient: Bletilla striata polysaccharides

Bletilla striata has been used for thousands of years and shows the functions of stopping bleeding, reducing swelling, and promoting healing in traditional applications. For Bletilla striata, Bletilla striata polysaccharides (BSP) is the main active ingredient, exhibiting biological functions of anti-inflammatory, anti-oxidant, anti-fibrotic, immune modulation, anti-glycation, and so on. In addition, BSP has exhibited the characteristics of excipient such as bio-adhesion, bio-degradability, and bio-safety and has been prepared into a series of preparations such as nanoparticles, microspheres, microneedles, hydrogels, etc. BSP, as both a drug and an excipient, has already aroused more and more attention. In this review, publications in recent years related to the extraction and identification, biological activities, and excipient application of BSP are reviewed. Specifically, we focused on the advances in the application of BSP as a formulation excipient. We hold opinion that BSP not only needed more researches in the mechanisms, but also the development into hydrogels, nano-formulations, tissue engineering, and so on. And we believe that this paper provides a beneficial reference for further BSP innovation and in-depth research and promotes the use of these natural products in pharmaceutical applications.

Carbonized Platycladus orientalis Derived Carbon Dots Accelerate Hemostasis through Activation of Platelets and Coagulation Pathways

Achieving rapid and effective hemostasis remains a multidisciplinary challenge. Here, distinctive functional carbon dots derived from carbonized Platycladus orientalis (CPO-CDs) are developed using one-step hydrothermal method. The negatively charged surface of CPO-CDs retains partial functional groups from CPO precursor, exhibiting excellent water solubility and high biocompatibility. Both rat liver injury model and tail amputation model have confirmed the rapid and effective hemostatic performance of CPO-CDs on exogenous hemorrhage. Further, on endogenous blood-heat hemorrhage syndrome rat model, CPO-CDs could inhibit hemorrhage and alleviate inflammation response. Interestingly, the excellent hemostasis performance of CPO-CDs is ascribed to activate exogenous coagulation pathway and common coagulation pathway. More importantly, metabolomics of rat plasma suggests that the hemostasis effect of CPO-CDs is closely related to platelet functions. Therefore, the designed in vitro experiments are performed and it is discovered that CPO-CDs significantly promote platelets adhesion, activation, and aggregation. Further, the underlying mechanism investigation suggests that Src/Syk signal pathway plays a key role in platelets activation triggered by CPO-CDs. Overall, CPO-CDs with rapid and excellent hemostatic performance are discovered for the first time, which could be an excellent candidate for the treatment of hemorrhagic diseases.

Metallic elements combine with herbal compounds upload in microneedles to promote wound healing: a review

Wound healing is a dynamic and complex restorative process, and traditional dressings reduce their therapeutic effectiveness due to the accumulation of drugs in the cuticle. As a novel drug delivery system, microneedles (MNs) can overcome the defect and deliver drugs to the deeper layers of the skin. As the core of the microneedle system, loaded drugs exert a significant influence on the therapeutic efficacy of MNs. Metallic elements and herbal compounds have been widely used in wound treatment for their ability to accelerate the healing process. Metallic elements primarily serve as antimicrobial agents and facilitate the enhancement of cell proliferation. Whereas various herbal compounds act on different targets in the inflammatory, proliferative, and remodeling phases of wound healing. The interaction between the two drugs forms nanoparticles (NPs) and metal-organic frameworks (MOFs), reducing the toxicity of the metallic elements and increasing the therapeutic effect. This article summarizes recent trends in the development of MNs made of metallic elements and herbal compounds for wound healing, describes their advantages in wound treatment, and provides a reference for the development of future MNs.