Electrospinning: An emerging technology to construct polymer-based nanofibrous scaffolds for diabetic wound healing

A chronic wound in diabetic patients is a major public health concern withsocioeconomic and clinical manifestations.The underlying medical condition of diabeticpatients deteriorates the wound through physiological,metabolic,molecular,and cellularpathologies.Consequently,a wound enters a vicious pathological inflammatory cycle.Many therapeutic approaches are in practice to manage diabetic wounds hence ensuringthe regeneration process.Polymer-based biomaterials have come up with hightherapeutic promises.Many efforts have been devoted,over the years,to build aneffective wound healing material using polymers.The electrospinning technique,although not new,has turned out to be one of the most effective strategies in buildingwound healing biomaterials due to the special structural advantages of electrospunnanofibers over the other formulations.In this review,careful integration of allelectrospinning approaches has been presented which will not only give an insight intothe current updates but also be helpful in the development of new therapeutic materialconsidering pathophysiological conditions of a diabetic wound.     

All-in-One: Multifunctional Hydrogel Accelerates Oxidative Diabetic Wound Healing through Timed-Release of Exosome and Fibroblast Growth Factor

The treatment of diabetic wounds remains a major challenge in clinical practice, with chronic wounds characterized by multiple drug-resistant bacterial infections, angiopathy, and oxidative damage to the microenvironment. Herein, a novel in situ injectable HA@MnO₂/FGF-2/Exos hydrogel is introduced for improving diabetic wound healing. Through a simple local injection, this hydrogel is able to form a protective barrier covering the wound, providing rapid hemostasis and long-term antibacterial protection. The MnO₂/ε-PL nanosheet is able to catalyze the excess H₂O₂ produced in the wound, converting it to O₂, thus not only eliminating the harmful effects of H₂O₂ but also providing O₂ for wound healing. Moreover, the release of M2-derived Exosomes (M2 Exos) and FGF-2 growth factor stimulates angiogenesis and epithelization, respectively. These in vivo and in vitro results demonstrate accelerated healing of diabetic wounds with the use of the HA@MnO₂/FGF-2/Exos hydrogel, presenting a viable strategy for chronic diabetic wound repair.     

Poly (ɛ‐caprolactone)–chitosan–poly (vinyl alcohol) nanofibrous scaffolds for skin excisional and burn wounds in a canine model

Poly (ɛ‐caprolactone)–chitosan–poly (vinyl alcohol) (PCL: Cs: PVA) nanofibrous blend scaffolds were known as useful materials for skin wound healing and would help the healing process about 50% faster at the final time point. From the previous studies by the authors, PCL: Cs: PVA (in 2: 1: 1.5 mass ratio) nanofibres showed high efficacy in healing on rat models. In this study, the scaffolds were examined in burn and excision wounds healing on dogs as bigger models. The scaffolds were applied on dorsum skin wounds (n  = 5) then macroscopic and microscopic investigations were carried out to measure the wounds areas and to track healing rate, respectively. Macroscopic results showed good aspect healing effect of scaffolds compared with control wounds especially after 21 days post‐operating for both cutting and burn wounds. Pathological studies showed that the healing rates of the wounds covered with PCL: Cs: PVA nanofibrous scaffolds were much rapid compared to untreated wounds in control group. The immunogenicity of the scaffolds in canine model was also investigated. The findings showed that nanofibrous blend scaffolds was not immunogenic in humoural immune responses. All these results indicated that PCL: Cs: PVA nanofibrous web could be considered as promising materials for wounds healings.Inspec keywords: nanofibres, nanomedicine, biomedical materials, polymer fibres, polymer blends, skin, woundsOther keywords: poly(ε‐caprolactone)‐chitosan‐poly (vinyl alcohol) nanofibrous blend scaffolds, skin excisional wounds, burn wounds, canine model, skin wound healing, dorsum skin wounds, macroscopic investigations, microscopic investigations, healing rate, cutting wounds, pathological study, humoural immune responses, nanofibrous web, immunogenicity, time 21 day     

On-Demand Removable Self-Healing and pH-Responsive Europium-Releasing Adhesive Dressing Enables Inflammatory Microenvironment Modulation and Angiogenesis for Diabetic Wound Healing

Current diabetic wound treatments remain unsatisfactory due to the lack of a comprehensive strategy that can integrate strong applicability (tissue adhesiveness, shape adaptability, fast self-healability, and facile dressing change) with the initiation and smooth connection of the cascade wound healing processes. Herein, benefiting from the multifaceted bonding ability of tannic acid to metal ions and various polymers, a family of tannin–europium coordination complex crosslinked citrate-based mussel-inspired bioadhesives (TE-CMBAs) are specially developed for diabetic wound healing. TE-CMBAs can gel instantly (< 60 s), possess favorable shape-adaptability, considerable mechanical strengths, high elasticity, considerable wet tissue adhesiveness (≈40 kPa), favorable photothermal antimicrobial activity, excellent anti-oxidant activity, biocompatibility, and angiogenetic property. The reversible hydrogen bond crosslinking and sensitive metal–phenolic coordination also confers TE-CMBAs with self-healability, pH-responsive europium ion and TA releasing properties and on-demand removability upon mixing with borax solution, enabling convenient painless dressing change and the smooth connection of inflammatory microenvironment modulation, angiogenesis promotion, and effective extracellular matrix production leveraging the acidic pH condition of diabetic wounds. This adhesive dressing provides a comprehensive regenerative strategy for diabetic wound management and can be extended to other complicated tissue healing scenarios.     

Zwitterionic 3D-Printed Non-Immunogenic Stealth Microrobots

Microrobots offer transformative solutions for non-invasive medical interventions due to their small size and untethered operation inside the human body. However, they must face the immune system as a natural protection mechanism against foreign threats. Here, non-immunogenic stealth zwitterionic microrobots that avoid recognition from immune cells are introduced. Fully zwitterionic photoresists are developed for two-photon polymerization 3D microprinting of hydrogel microrobots with ample functionalization: tunable mechanical properties, anti-biofouling and non-immunogenic properties, functionalization for magnetic actuation, encapsulation of biomolecules, and surface functionalization for drug delivery. Stealth microrobots avoid detection by macrophage cells of the innate immune system after exhaustive inspection ( > 90 hours), which has not been achieved in any microrobotic platform to date. These versatile zwitterionic materials eliminate a major roadblock in the development of biocompatible microrobots, and will serve as a toolbox of non-immunogenic materials for medical microrobot and other device technologies for bioengineering and biomedical applications.     

High‐Resolution SPECT Imaging of Stimuli‐Responsive Soft Microrobots

Untethered small‐scale robots have great potential for biomedical applications. However, critical barriers to effective translation of these miniaturized machines into clinical practice exist. High resolution tracking and imaging in vivo is one of the barriers that limit the use of micro‐ and nanorobots in clinical applications. Here, the inclusion of radioactive compounds in soft thermoresponsive magnetic microrobots is investigated to enable their single‐photon emission computed tomography imaging. Four microrobotic platforms differing in hydrogel structure and four ^99mTc[Tc]‐based radioactive compounds are investigated in order to achieve optimal contrast agent retention and optimal imaging. Single microrobot imaging of structures as low as 100 µm in diameter, as well as tracking of shape switching from tubular to planar configurations by inclusion of ^99mTc[Tc] colloid in the hydrogel structure, is reported.     

Small extracellular vesicles secreted by urine-derived stem cells enhanced wound healing in aged mice by ameliorating cellular senescence

Regeneration of chronic skin wounds in tissue is still a key challenge in regenerative medicine because of the accumulation of senescent cells and increasing secretion of s¨enescence-associated secretory phenotype(SASP)in the wound site.Recently,some studies have reported that small extracellular vesicles(sEVs)derived from stem cells can alleviate cellular senescence with very low risk of tumorigenesis and immune responses.As our previous studies have shown that urine-derived stem cells(USCs)can be obtained easily and noninvasively and sEVs derived from USCs(USC-sEVs)have capabilities of regenerating tissue injuries,using USC-sEVs to enhance chronic skin wound healing in aged tissue might be a feasible and efficient strategy.Therefore,in this study,the USC-sEVs were collected and firstly loaded in a human acellular amniotic membrane(HAAM)for controlled releasing and locating the USC-sEVs in the wound site before they were implanted into a chronic skin wound in aged mice.In vivo results showed that the USC-sEVs in HAAM could effectively accelerate the wound healing by ameliorating cellular senescence and reducing the secretion of SASP in the aged skin wounds.To elucidate the mechanism,USC-sEVs were used to in vitro culture human dermal fibroblasts(HDFs)and results showed that USC-sEVs could rejuvenate senescent fibroblasts by reversing the aging phenotypes of senescent HDFs and efficiently reducing the secretion of SASP after they activated the Sirt1 pathway.Therefore,USC-sEVs are efficient for enhancing wound healing in aged mice by ameliorating cellular senescence.     

Effect of novel blend nanofibrous scaffolds on diabetic wounds healing

Chitosan‐poly (vinyl alcohol) (Cs: PVA) (2:3) and poly (caprolactone)‐chitosan‐poly (vinyl alcohol) (PCL: Cs: PVA) (2:1:1.5) nanofibrous blend scaffolds were fabricated using the electrospinning technique in the authors’ previous studies. The results of the previous studies confirmed the high biological properties of the scaffolds and their ability in healing of burn and excision wounds on rat model. In the present study, the biological scaffolds were applied on diabetic dorsum skin wounds and diabetic foot wound on rat models (n = 16). Macroscopic and microscopic investigations were carried out using digital images and haematoxylin and eosin (H&E) staining respectively, to measure the wound areas and to track wound healing rate. It was found that at all time points the areas of wounds treated with nanofibrous scaffolds were smaller compared with the controls. Pathological results showed much better healing efficacy for the test samples compared with the control ones. Pathological investigations proved the presence of more pronounced granulation tissues in the scaffold‐treated wounds compared with the control ones. At 20 days post excision, the scaffold‐treated groups achieved complete repair. The results indicated that Cs: PVA and PCL: Cs: PVA nanofibrous webs could be considered to be promising materials for burn, excision and diabetic wounds healing.Inspec keywords: wounds, diseases, biomedical materials, polymer blends, nanofibres, polymer fibres, nanomedicine, nanofabrication, electrospinning, skin, cellular biophysics, caesium, medical image processing, patient treatmentOther keywords: chitosan‐poly (vinyl alcohol), poly (caprolactone)‐chitosan‐poly (vinyl alcohol), nanofibrous blend scaffolds, electrospinning, biological properties, rat model, diabetic dorsum skin wound healing, diabetic foot wounds, rat models, digital imaging, H&amp;E staining, pathology, granulation tissues, PCL‐Cs‐PVA nanofibrous webs, excision wound healings, burn wound healings     

A Multidrug Delivery Microrobot for the Synergistic Treatment of Cancer

Multidrug combination therapy provides an effective strategy for malignant tumor treatment. This paper presents the development of a biodegradable microrobot for on-demand multidrug delivery. By combining magnetic targeting transportation with tumor therapy, it is hypothesized that loading multiple drugs on different regions of a single magnetic microrobot can enhance a synergistic effect for cancer treatment. The synergistic effect of using two drugs together is greater than that of using each drug separately. Here, a 3D-printed microrobot inspired by the fish structure with three hydrogel components: skeleton, head, and body structures is demonstrated. Made of iron oxide (Fe₃O₄) nanoparticles embedded in poly(ethylene glycol) diacrylate (PEGDA), the skeleton can respond to magnetic fields for microrobot actuation and drug-targeted delivery. The drug storage structures, head, and body, made by biodegradable gelatin methacryloyl (GelMA) exhibit enzyme-responsive cargo release. The multidrug delivery microrobots carrying acetylsalicylic acid (ASA) and doxorubicin (DOX) in drug storage structures, respectively, exhibit the excellent synergistic effects of ASA and DOX by accelerating HeLa cell apoptosis and inhibiting HeLa cell metastasis. In vivo studies indicate that the microrobots improve the efficiency of tumor inhibition and induce a response to anti-angiogenesis. The versatile multidrug delivery microrobot conceptualized here provides a way for developing effective combination therapy for cancer.     

Magnetically Powered Immunogenic Macrophage Microrobots for Targeted Multimodal Cancer Therapy (Small 42/2023)

Motile microrobots open a new realm for disease treatment. However, the concerns of possible immune elimination, targeted capability and limited therapeutic avenue of microrobots constrain its practical biomedical applications. Herein, a biogenic macrophage-based microrobot loaded with magnetic nanoparticles and bioengineered bacterial outer membrane vesicles (OMVs), capable of magnetic propulsion, tumor targeting, and multimodal cancer therapy is reported. Such cell robots preserve intrinsic properties of macrophages for tumor suppression and targeting, and bioengineered OMVs for antitumor immune regulation and fused anticancer peptides. Cell robots display efficient magnetic propulsion and directional migration in the confined space. In vivo tests show that cell robots can accumulate at the tumor site upon magnetic manipulation, coupling with tumor tropism of macrophages to greatly improve the efficacy of its multimodal therapy, including tumor inhibition of macrophages, immune stimulation, and antitumor peptides of OMVs. This technology offers an attractive avenue to design intelligent medical microrobots with remote manipulation and multifunctional therapy capabilities for practical precision treatment.     

Assessment of reinforced poly(ethylene glycol) chitosan hydrogels as dressings in a mouse skin wound defect model

Wound dressings of chitosan are biocompatible, biodegradable, antibacterial and hemostatic biomaterials. However, applications for chitosan are limited due to its poor mechanical properties. Here, we conducted an in vivo mouse angiogenesis study on reinforced poly(ethylene glycol) (PEG)-chitosan (RPC) hydrogels. RPC hydrogels were formed by cross-linking chitosan with PEGs of different molecular weights at various PEG to chitosan ratios in our previous paper. These dressings can keep the wound moist, had good gas exchange capacity, and was capable of absorbing or removing the wound exudate. We examined the ability of these RPC hydrogels and neat chitosan to heal small cuts and full-thickness skin defects on the backs of male Balb/c mice. Histological examination revealed that chitosan suppressed the infiltration of inflammatory cells and accelerated fibroblast proliferation, while PEG enhanced epithelial migration. The RPC hydrogels promoted wound healing in the small cuts and full layer wounds. The optimal RPC hydrogel had a swelling ratio of 100% and a water vapor transmission rate (WVTR) of about 2000 g/m²/day. In addition, they possess good mechanical property and appropriate degradation rates. Thus, the optimal RPC hydrogel formulation functioned effectively as a wound dressing and promoted wound healing.     

Advanced nanofibrous textile-based dressing material for treating chronic wounds

In the present work, an electrospun nanofibrous textile composed of polyurethane (PU), sodium bicarbonate (\(\hbox {NaHCO}_{3}\)) and pantothenic acid (PA) is developed for treating chronic wounds. Wounds are a common health problem and in particular, the chronic wounds such as vascular ulcers, diabetic ulcers and pressure ulcers cause a large number of morbidity and mortality. The main problems of the chronic wounds are prolonged inflammation phase and presence of acidic environment. These events deactivate the operation of growth factors and also the progression of natural healing mechanism. Hence, various types of advanced textile-based dressings are developed to address the clinical complications associated with chronic wound management. The prepared electrospun scaffolds were characterized to study their physicochemical and haemocompatible properties. The scanning electron microscopy micrographs depicted continuous, smooth-interconnected nanofibrous morphology of PU–NaHCO\(_{3}\)–PA scaffolds. The Fourier transform infrared spectroscopy spectra indicated the addition of NaHCO\(_{3}\) and PA-based hydrophilic chemical groups, which significantly enhanced the wettability of the composites. Further, the PU–NaHCO\(_{3}\)–PA composite membrane inferred to have a highly porous structure with the mean porosity of 79.4 ± 4.8%, which may provide a conducive environment for adherence and proliferation of skin cells. The composite scaffold also offers a highly haemocompatible surface by delaying coagulation of blood through contact activation pathways and by limiting red blood cells damage. Therefore, the excellent physicochemical properties, blood compatibility and the delivery of PA are anticipated to speed up the impaired healing process of chronic wounds.     

Development of nanotechnology for advancement and application in wound healing: a review

Wound healing is a series of different dynamic and complex phenomena. Many studies have been carried out based on the type and severity of wounds. However, to recover wounds faster there are no suitable drugs available, which are highly stable, less expensive as well as has no side effects. Nanomaterials have been proven to be the most promising agent for faster wound healing among all the other wound healing materials. This review briefly discusses the recent developments of wound healing by nanotechnology, their applicability and advantages. Nanomaterials have unique physicochemical, optical, and biological properties. Some of them can be directly applied for wound healing or some of them can be incorporated into scaffolds to create hydrogel matrix or nanocomposites, which promote wound healing through their antimicrobial, as well as selective anti‐ and pro‐inflammatory, and proangiogenic properties. Owing to their high surface area to volume ratio, nanomaterials have not only been used for drug delivery vectors but also can affect wound healing by influencing collagen deposition and realignment and provide approaches for skin tissue regeneration.Inspec keywords: skin, wounds, cellular biophysics, drug delivery systems, tissue engineering, hydrogels, nanocomposites, proteins, nanomedicineOther keywords: wound healing materials, nanomaterials, nanotechnology, proangiogenic properties, proinflammatory properties, collagen deposition, drug delivery vectors, skin tissue regeneration     

Rise of cyborg microrobot: different story for different configuration

By integrating organic parts achieved through evolution and inorganic parts developed by human civilisation, the cyborg microrobot is rising by taking advantage of the high flexibility, outstanding energy efficiency, extremely exquisite structure in the natural components and the fine upgradability, nice controllability in the artefact parts. Compared to the purely synthetic microrobots, the cyborg microrobots, due to the exceptional biocompatibility and biodegradability, have already been utilised in in situ diagnosis, precise therapy and other biomedical applications. In this review, through a thorough summary of recent advances of cyborg microrobots, the authors categorise the cyborg microrobots into four major classes according to the configuration between biomaterials and artefact materials, i.e. microrobots integrated inside living cell, microrobots modified with biological debris, microrobots integrated with single cell and microrobots incorporated with multiple cells. Cyborg microrobots with the four types of configurations are introduced and summarised with the combination approaches, actuation mechanisms, applications and challenges one by one. Moreover, they conduct a comparison among the four different cyborg microrobots to guide the actuation force promotion, locomotion control refinement and future applications. Finally, conclusions and future outlook of the development and potential applications of the cyborg microrobots are discussed.Inspec keywords: medical robotics, cellular biophysics, mobile robots, molecular biophysics, polymers, microrobotsOther keywords: locomotion control refinement, actuation force promotion, combination approaches, biological debris, living cell, artefact materials, biomaterials, biomedical applications, biodegradability, exceptional biocompatibility, natural components, energy efficiency, human civilisation, purely synthetic microrobots, cyborg microrobot     

Evaluation of the wound healing efficacy of chemical and phytogenic silver nanoparticles

Wound healing requires a series of cellular events and a cascade of co‐ordinated and systemic biochemical events. Silver nanoparticles possess many beneficial properties for wound management including antibacterial, anti‐inflammatory and pro‐healing properties. In this study, the authors investigated the wound healing properties of Cinnamomum verum extract mediated nanosilver (CENS) particles in comparison with 1% povidone iodine, citrate mediate NS and CE treatments. The topical application of CENS showed good antibacterial activity and accelerated wound healing with complete epithelialisation and normal re‐growth of hair in all three models of study: namely, excision, incision and dead space models in rats compared with all other treatments. CENS was also found to promote collagen synthesis, stabilise wound besides countering oxidative stress and stimulating cellular proliferation CENS could be a novel therapeutic agent for wound management.Inspec keywords: silver, nanoparticles, nanomedicine, wounds, antibacterial activity, biomedical materials, biochemistry, cellular biophysics, proteinsOther keywords: wound healing efficacy, chemical nanoparticles, phytogenic silver nanoparticles, cellular events, systemic biochemical events, wound management, antibacterial properties, anti‐inflammatory properties, pro‐healing properties, Cinnamomum verum extract mediated nanosilver particles, CENS, complete epithelialisation, normal hair regrowth, excision model, incision model, dead space model, rats, collagen synthesis, oxidative stress, cellular proliferation, therapeutic agent, Ag     

Bioinspired Soft Microrobots with Precise Magneto-Collective Control for Microvascular Thrombolysis

New-era soft microrobots for biomedical applications need to mimic the essential structures and collective functions of creatures from nature. Biocompatible interfaces, intelligent functionalities, and precise locomotion control in a collective manner are the key parameters to design soft microrobots for the complex bio-environment. In this work, a biomimetic magnetic microrobot (BMM) inspired by magnetotactic bacteria (MTB) with speedy motion response and accurate positioning is developed for targeted thrombolysis. Similar to the magnetosome structure in MTB, the BMM is composed of aligned iron oxide nanoparticle (MNP) chains embedded in a non-swelling microgel shell. Linear chains in BMMs are achieved due to the interparticle dipolar interactions of MNPs under a static magnetic field. Simulation results show that, the degree and speed of assembly is proportional to the field strength. The BMM achieves the maximum speed of 161.7 µm s⁻¹ and accurate positioning control under a rotating magnetic field with less than 4% deviation. Importantly, the locomotion analyses of BMMs demonstrate the frequency-dependent synchronization under 8 Hz and asynchronization at higher frequencies due to the increased drag torque. The BMMs can deliver and release thrombolytic drugs via magneto-collective control, which is promising for ultra-minimal invasive thrombolysis.     

Nanozyme-Based Supramolecular Self-Assembly As an Artificial Host Defense System For Treatment of Bacterial Infections

The proper functioning of host defense system (HDS) is the key to combating bacterial infection in biological organisms. However, the delicate HDS may be dysfunctional or dysregulated, resulting in persistent infection, tissue damage, or delayed wound healing. Herein, a powerful artificial “host defense system” (aHDS) is designed and constructed for treatment of bacterial infections. First, the aHDS can quickly trap the bacteria by electrostatic interactions. Next, the system can be stimulated to produce large amounts of cytotoxic reactive oxygen species (ROS) and exert strong antibacterial effects, which can further regulate the immune microenvironment, leading to macrophage polarization from M0 to pro-inflammatory phenotype (M1) for synergistic bacteria killing. At the later stages, the system can exhibit excellent antioxidant enzyme-like activities to reprogram the M1 macrophage to anti-inflammatory phenotype (M2) for accelerating wound healing. This powerful aHDS can effectively combat the bacteria and avoid excessive inflammatory responses for the treatment of bacteria-infected wounds.     

Local Immunomodulation Using an Adhesive Hydrogel Loaded with miRNA‐Laden Nanoparticles Promotes Wound Healing

Chronic wounds are characterized by impaired healing and uncontrolled inflammation, which compromise the protective role of the immune system and may lead to bacterial infection. Upregulation of miR‐223 microRNAs (miRNAs) shows driving of the polarization of macrophages toward the anti‐inflammatory (M2) phenotype, which could aid in the acceleration of wound healing. However, local‐targeted delivery of microRNAs is still challenging, due to their low stability. Here, adhesive hydrogels containing miR‐223 5p mimic (miR‐223*) loaded hyaluronic acid nanoparticles are developed to control tissue macrophages polarization during wound healing processes. In vitro upregulation of miR‐223* in J774A.1 macrophages demonstrates increased expression of the anti‐inflammatory gene Arg‐1 and a decrease in proinflammatory markers, including TNF‐α, IL‐1β, and IL‐6. The therapeutic potential of miR‐223* loaded adhesive hydrogels is also evaluated in vivo. The adhesive hydrogels could adhere to and cover the wounds during the healing process in an acute excisional wound model. Histological evaluation and quantitative polymerase chain reaction (qPCR) analysis show that local delivery of miR‐223* efficiently promotes the formation of uniform vascularized skin at the wound site, which is mainly due to the polarization of macrophages to the M2 phenotype. Overall, this study demonstrates the potential of nanoparticle‐laden hydrogels conveying miRNA‐223* to accelerate wound healing.     

Magnetically Driven Undulatory Microswimmers Integrating Multiple Rigid Segments

Mimicking biological locomotion strategies offers important possibilities and motivations for robot design and control methods. Among bioinspired microrobots, flexible microrobots exhibit remarkable efficiency and agility. These microrobots traditionally rely on soft material components to achieve undulatory propulsion, which may encounter challenges in design and manufacture including the complex fabrication processes and the interfacing of rigid and soft components. Herein, a bioinspired magnetically driven microswimmer that mimics the undulatory propulsive mechanism is proposed. The designed microswimmer consists of four rigid segments, and each segment is connected to the succeeding segment by joints. The microswimmer is fabricated integrally by 3D laser lithography without further assembly, thereby simplifying microrobot fabrication while enhancing structural integrity. Experimental results show that the microswimmer can successfully swim forward along guided directions via undulatory locomotion in the low Reynolds number (Re) regime. This work demonstrates for the first time that the flexible characteristic of microswimmers can be emulated by 3D structures with multiple rigid segments, which broadens possibilities in microrobot design. The proposed magnetically driven microswimmer can potentially be used in biomedical applications, such as medical diagnosis and treatment in precision medicine.     

Preparation,characterization, and in vivo evaluation of nano formulations of ferulic acid in diabetic wound healing

Diabetes mellitus is most common disorder characterize by hyperglycemia. Chronic hyperglycemia may lead to over production of free radicals thereby results in oxidative stress which impaired healing of wounds. Ferulic acid (FA) has been shown to have antidiabetic and antioxidant properties. The aim of the present study was to develop Ferulic acid nanoparticles and to study its hypoglycemic and wound healing activities. Ferulic acid-poly(lactic-co-glycolic acid) (FA-PLGA) nanoparticles were prepared by nano precipitation method. The prepared FA-PLGA nanoparticles had an average size of 240?nm. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) analysis showed the prepared FA-PLGA nanoparticles were spherical in shape. Drug encapsulation assay showed that 88.49% FA was encapsulated in PLGA. Carbopol 980 was used to formulate FA-PLGA nanoparticles loaded hydrogel. FA-loaded polymeric nanoparticles dispersion (oral administration) and FA-loaded polymeric nanoparticles based hydrogel (topical administration) treated wounds were found to epithelize faster as compared with diabetic wound control group. The hydroxyproline content increased significantly when compared with diabetic wound control. Therefore, the results indicate that FA significantly promotes wound healing in diabetic rats.