Preparation and Characterization of Chitosan/β-Glycerophosphate Thermal-Sensitive Hydrogel Reinforced by Graphene Oxide

Production and performance evaluation of chitosan/collagen/honey nanofibrous membranes for wound dressing applications

Persistent bacterial infections are the leading risk factor that complicates the healing of chronic wounds. In this work, we formulate mixtures of polyvinyl alcohol (P), chitosan (CH), collagen (C), and honey (H) to produce nanofibrous membranes with healing properties. The honey effect at concentrations of 0 % (PCH and PCHC), 5 % (PCHC-5H), 10 % (PCHC-10H), and 15 % (PCHC-15H) on the physicochemical, antibacterial, and biological properties of the developed nanofibers was investigated. Morphological analysis by SEM demonstrated that PCH and PCHC nanofibers had a uniform and homogeneous distribution on their surfaces. However, the increase in honey content increased the fiber diameter (118.11-420.10) and drastically reduced the porosity of the membranes (15.79-92.62 nm). The addition of honey reduces the water vapor transmission rate (WVTR) and the adsorption properties of the membranes. Mechanical tests revealed that nanofibers were more flexible and elastic when honey was added, specifically the PCHC-15H nanofibers with the lowest modulus of elasticity (15 MPa) and the highest elongation at break (220 %). Also, honey significantly improved the antibacterial efficiency of the nanofibers, mainly PCHC-15H nanofibers, which presented the best bacterial reduction rates against Staphylococcus aureus (59.84 %), Pseudomonas aeruginosa (47.27 %), Escherichia coli (65.07 %), and Listeria monocytogenes (49.58 %). In vitro tests with cell cultures suggest that nanofibers were not cytotoxic and exhibited excellent biocompatibility with human fibroblasts (HFb) and keratinocytes (HaCaT), since all treatments showed higher or similar cell viability as opposed to the cell control. Based on the findings, PVA-chitosan-collagen-honey nanofibrous membranes have promise as an antibacterial dressing substitute.

Current trend on preparation, characterization and biomedical applications of natural polysaccharide-based nanomaterial reinforcement hydrogels: A review

The tunable properties of hydrogels have led to their widespread use in various biomedical applications such as wound treatment, drug delivery, contact lenses, tissue engineering and 3D bioprinting. Among these applications, natural polysaccharide-based hydrogels, which are fabricated from materials like agarose, alginate, chitosan, hyaluronic acid, cellulose, pectin and chondroitin sulfate, stand out as preferred choices due to their biocompatibility and advantageous fabrication characteristics. Despite the inherent biocompatibility, polysaccharide-based hydrogels on their own tend to be weak in physiochemical and mechanical properties. Therefore, further reinforcement in the hydrogel is necessary to enhance its suitability for specific applications, ensuring optimal performance in diverse settings. Integrating nanomaterials into hydrogels has proven effective in improving the overall network and performance of the hydrogel. This approach also addresses the limitations associated with pure hydrogels. Next, an overview of recent trends in the fabrication and applications of hydrogels was presented. The characterization of hydrogels was further discussed, focusing specifically on the reinforcement achieved with various hydrogel materials used so far. Finally, a few challenges associated with hydrogels by using polysaccharide-based nanomaterial were also presented.

Co-encapsulation of Shirazi thyme (Zataria multiflora) essential oil and nisin using caffeic acid grafted chitosan nanogel and the effect of this nanogel as a bio-preservative in Iranian white cheese

The current study aims to co-encapsulate Shirazi thyme (Zataria multiflora) essential oil (ZEO) and nisin into chitosan nanogel as an antimicrobial and antioxidant agent to enhance the shelf-life of cheese. Chitosan-caffeic acid (CS-CA) nanogel was produced to co-encapsulate Zataria multiflora essential oil and nisin. This nanogel was characterized by dynamic light scattering (DLS), Fourier Transform Infrared (FTIR) spectroscopic analysis, X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM) images. The effect of free (TFZN) and encapsulated ZEO-nisin in chitosan nanogel (TCZN) on the chemical and microbiological properties of Iranian white cheese was assessed. The particle size, polydispersity index value (PDI), zeta potential, antioxidant activity, and encapsulation efficiency of the optimal chitosan-ZEO-nisin nanogel were 421.6 nm, 0.343, 34.0 mV, 71.06%-82.69%, and 41.3 ± 0.5%, 0.79 ± 0.06 mg/mL. respectively. FTIR and XRD approved ZEO and nisin entrapment within chitosan nanogel. The chitosan nanogel showed a highly porous surface with an irregular shape. The bioactive compounds of ZEO and nisin decreased the pH changes in cheese. On the 60th day of storage, the acidity of treated samples was significantly lower than that of control. Although the lowest anisidine index value was observed in samples treated with sodium nitrate (NaNO3) (TS), there was no significant difference between this sample and TCZN. The lowest microbial population was observed in TCZN and TS. After 60 days of ripening, Coliforms were not detected in the culture medium of TCZN and TS. The results can contribute to the development of a natural preservative with the potential for application in the dairy industry.

Amorphous magnesium phosphate-graphene oxide nano particles laden 3D-printed chitosan scaffolds with enhanced osteogenic potential and antibacterial properties

The utilization of 3D printing technology for the fabrication of graft substitutes in bone repair holds immense promise. However, meeting the requirements for printability, bioactivity, mechanical strength, and biological properties of 3D printed structures concurrently poses a significant challenge. In this study, we introduce a novel approach by incorporating amorphous magnesium phosphate-graphene oxide (AMP-GO) into a thermo-crosslinkable chitosan/β glycerol phosphate (CS/GP) ink. We fabricated thermo-crosslinkable CS inks containing varying concentrations (10 %, 20 %, or 30 % weight) of AMP-GO. The 3D printed scaffolds incorporating 20 % AMP-GO exhibited significantly improved mechanical properties, with compressive strengths of 4.5 ± 0.06 MPa compared to 0.5 ± 0.03 MPa for CS printed scaffolds. Moreover, the CS/AMP-GO inks demonstrated enhanced antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria, attributed to the release of magnesium cations and the performance of GO. Additionally, CS/20AMP-GO ink facilitated increased adhesion, viability, proliferation, and osteogenic differentiation of mesenchymal stem cells (MSCs), as evidenced by the upregulation of ALP, COL1, and Runx2 expression, which were elevated 9.8, 6.5, and >22 times, respectively, compared to pure CS scaffolds. Considering its exceptional in vivo osteogenic potential, we anticipate that the CS/20AMP-GO ink holds great potential for 3D printing of bone grafts.

Au nanozyme-based multifunctional hydrogel for inflammation visible monitoring and treatment

Chronic inflammation can delay wound healing, eventually leading to tissue necrosis and even cancer. Developing real-time intelligent inflammation monitoring and treatment to achieve effective wound management is important to promote wound healing. In this study, a smart multifunctional hydrogel (Hydrogel@Au NCs&DG) was proposed to monitor and treat the wound inflammation. It was prepared by mixing 3-carboxy-phenylboronic acid modified chitosan (CS-cPBA), β-glycerophosphate (β-GP), albumin-protected gold nanoclusters (BSA-Au NCs), and dipotassium glycyrrhizinate (DG) about 10 s. In this hydrogel, CS-cPBA and β-GP are crosslinked together by boric acid ester bond and hydrogen bond to form the main hydrogel network, endowing the hydrogel with self-healing and injectable properties to adapt irregular wounds. Importantly, the as-prepared hydrogel with good biocompatibility and excellent adhesion property could directly determine the H2O2 to monitor the wound microenvironment by visible fluorescence change of BSA-Au NCs and then guide the frequency of dressing change to eliminate inflammation. The results demonstrated that the as-prepared smart hydrogel could be expected to serve as an intelligent wound dressing to promote inflammation-infected wound healing.

A dihydromyricetin-loaded phellinus igniarius polysaccharide/l-arginine modified chitosan-based hydrogel for promoting wound recovery in diabetic mice via JNK and TGF-β/Smad signaling pathway

The wound of diabetes has long-term excessive inflammation leading to wound fibrosis and scar formation. In the process of diabetic wound healing, good wound dressing is required for intervention. In this study, we designed a dihydromyricetin-loaded hydrogel (PCD) based on phellinus igniarius polysaccharide and l-arginine modified chitosan as an alternative material to promote diabetes wound healing. PCD had a uniform porous structure, good thermal stability, excellent mechanical properties, high water absorption, excellent antioxidant and anti-inflammatory activities and good biocompatibility and biodegradability. In addition, in the full-thickness skin trauma model of diabetes, PCD significantly inhibited the JNK signaling pathway to reduce inflammatory response, and significantly down-regulated the expression of TGF-β1, Smad2, Smad3 and Smad4 to directly inhibit the TGF-β/Smad signaling pathway to accelerate wound healing and slow down scar formation in diabetes mice. Therefore, PCD has a broad application prospect in promoting diabetes wound healing.

Bilayer wound dressing composed of asymmetric polycaprolactone membrane and chitosan-carrageenan hydrogel incorporating storax balsam

A comprehensive approach is needed to develop multifunctional wound dressing that is simple yet efficient. In this work, Liquidambar orientalis Mill. storax loaded hydroxyethyl chitosan (HECS)-carrageenan (kC) based hydrogel (HECS-kC) and polydopamine coated asymmetric polycaprolactone membrane (PCL-DOP) were used to develop a multifunctional and modular bilayer wound dressing. Asymmetric PCL-DOP membrane was prepared by non-solvent induced phase separation (NIPS) followed by polydopamine coating and demonstrated an excellent barrier against bacteria while allowing permeability for 5.45 ppm dissolved‑oxygen and 2130 g/m2 water vapor transmission in 24 h in addition to 805 kPa tensile strength. Storax loaded HECS-kC hydrogel, on the other hand, demonstrated a pH-responsive degradation and swelling to provide necessary conditions to facilitate wound healing. The hydrogels showed stretchability above 140 %, mild adhesive strength on sheep skin and PCL-DOP membrane, while the storax incorporation enhanced antibacterial and antioxidant activity. Furthermore, rat full-thickness skin defect model showed that the developed bilayer wound dressing could significantly facilitate wound healing compared to Tegaderm™ and control groups. This study shows that the bilayered wound dressing has the potential to be used as a simple and effective wound care system.

β-Tricalcium Phosphate-Loaded Chitosan-Based Thermosensitive Hydrogel for Periodontal Regeneration

The current treatment for periodontitis is aimed at resolving gingival inflammation, whilst complete periodontal tissue regeneration is not predictable, and it represents a therapeutic challenge. Injectable biomaterials hold tremendous potential in dental tissue regeneration. This study aimed to investigate the ability of an injectable thermosensitive β-tricalcium phosphate (β-TCP) and chitosan-based hydrogel to carry cells and promote periodontal tissue regeneration. In this study, different concentrations of β-TCP-loaded chitosan hydrogels were prepared (0%, 2%, 4%, or 6% β-TCP, 10% β-glycerol phosphate, and 1.5% chitosan). The characteristics of the hydrogels were tested using rheology, a scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), degradation, and biological analyses. The new biomaterial showed a sol-gel transformation ability at body temperature and exhibited excellent chemical and physical characteristics, whilst the existence of β-TCP enhanced the structure and the properties of the hydrogels. The SEM confirmed the three-dimensional networks of the hydrogels, and the typical rheological properties of strong gel were observed. The EDX and XRD validated the successful incorporation of β-TCP, and similar patterns between different groups were found in terms of the FTIR spectra. The stable structure of the hydrogels under 100 °C was confirmed via DSC. Biological tests such as Alamar Blue assay and Live/Dead staining confirmed the remarkable biocompatibility of the hydrogels with pre-osteoblast MC3T3-E1 and human gingival fibroblast (HGF) cells for 14 days, and the results were validated with confocal imaging. This preliminary study shows great promise for the application of the β-TCP-loaded thermosensitive chitosan hydrogels as a scaffold in periodontal bone and soft tissue repair.

Injectable hydrogel for sustained delivery of progranulin derivative Atsttrin in treating diabetic fracture healing

Hydrogels with long-term storage stability, controllable sustained-release properties, and biocompatibility have been garnering attention as carriers for drug/growth factor delivery in tissue engineering applications. Chitosan (CS)/Graphene Oxide (GO)/Hydroxyethyl cellulose (HEC)/β-glycerol phosphate (β-GP) hydrogel is capable of forming a 3D gel network at physiological temperature (37 °C), rendering it an excellent candidate for use as an injectable biomaterial. This work focused on an injectable thermo-responsive CS/GO/HEC/β-GP hydrogel, which was designed to deliver Atsttrin, an engineered derivative of a known chondrogenic and anti-inflammatory growth factor-like molecule progranulin. The combination of the CS/GO/HEC/β-GP hydrogel and Atsttrin provides a unique biochemical and biomechanical environment to enhance fracture healing. CS/GO/HEC/β-GP hydrogels with increased amounts of GO exhibited rapid sol-gel transition, higher viscosity, and sustained release of Atsttrin. In addition, these hydrogels exhibited a porous interconnected structure. The combination of Atsttrin and hydrogel successfully promoted chondrogenesis and osteogenesis of bone marrow mesenchymal stem cells (bmMSCs) in vitro. Furthermore, the work also presented in vivo evidence that injection of Atsttrin-loaded CS/GO/HEC/β-GP hydrogel stimulated diabetic fracture healing by simultaneously inhibiting inflammatory and stimulating cartilage regeneration and endochondral bone formation signaling pathways. Collectively, the developed injectable thermo-responsive CS/GO/HEC/βG-P hydrogel yielded to be minimally invasive, as well as capable of prolonged and sustained delivery of Atsttrin, for therapeutic application in impaired fracture healing, particularly diabetic fracture healing.

Enhanced Osteogenesis Potential of MG-63 Cells through Sustained Delivery of VEGF via Liposomal Hydrogel

The challenges of using VEGF to promote osteoblastic differentiation include a short half-life and a narrow therapeutic window. A carrier system combining hydrogel and liposomes may improve the therapeutic efficacy of VEGF for bone regeneration. This study aimed to investigate the effects of delivery of VEGF via liposomal hydrogel on the osteogenesis of MG-63 cells. Liposomal hydrogel scaffold was fabricated and then characterized in terms of the morphological and chemical properties using FESEM and FTIR. In 2.5D analysis, the MG-63 cells were cultured on liposomal hydrogel + VEGF as the test group. The osteogenic effects of VEGF were compared with the control groups, i.e., hydrogel without liposomes + VEGF, osteogenic medium (OM) supplemented with a bolus of VEGF, and OM without VEGF. Cell morphology, viability, and differentiation and mineralization potential were investigated using FESEM, MTT assay, ALP activity, and Alizarin red staining. The characterization of scaffold showed no significant differences in the morphological and chemical properties between hydrogel with and without liposomes (p > 0.05). The final 2.5D culture demonstrated that cell proliferation, differentiation, and mineralization were significantly enhanced in the liposomal hydrogel + VEGF group compared with the control groups (p < 0.05). In conclusion, liposomal hydrogel can be used to deliver VEGF in a sustained manner in order to enhance the osteogenesis of MG-63 cells.

Application of polyvinyl alcohol/chitosan copolymer hydrogels in biomedicine: A review

Hydrogels is a hydrophilic, cross-linked polymer of three-dimensional network structures. The application of hydrogels prepared from a single polymer in the biomedical field has many drawbacks. The functional blend of polyvinyl alcohol and chitosan allows hydrogels to have better and more desirable properties than those produced from a single polymer, which is a good biomaterial for development and design. In this paper, we have reviewed the progress in the application of polyvinyl alcohol/chitosan composite hydrogels in various medical fields, the different cross-linking agents and cross-linking methods, and the research progress in the optimization of composite hydrogels for their subsequent wide range of biomedical applications.

Injectable Thermoresponsive Hydrogels for Cancer Therapy: Challenges and Prospects

The enervating side effects of chemotherapeutic drugs have necessitated the use of targeted drug delivery in cancer therapy. To that end, thermoresponsive hydrogels have been employed to improve the accumulation and maintenance of drug release at the tumour site. Despite their efficiency, very few thermoresponsive hydrogel-based drugs have undergone clinical trials, and even fewer have received FDA approval for cancer treatment. This review discusses the challenges of designing thermoresponsive hydrogels for cancer treatment and offers suggestions for these challenges as available in the literature. Furthermore, the argument for drug accumulation is challenged by the revelation of structural and functional barriers in tumours that may not support targeted drug release from hydrogels. Other highlights involve the demanding preparation process of thermoresponsive hydrogels, which often involves poor drug loading and difficulties in controlling the lower critical solution temperature and gelation kinetics. Additionally, the shortcomings in the administration process of thermosensitive hydrogels are examined, and special insight into the injectable thermosensitive hydrogels that reached clinical trials for cancer treatment is provided.

Pharmacokinetic Evaluation of Thermosensitive Sustained Release Formulations Developed for Subcutaneous Delivery of Protein Therapeutics

Injectable, thermosensitive hydrogels, constructed from cross-linked polymers, can offset the limitations of other sustained release delivery systems, overcome constrains of available therapies, and improve patient compliance to chronic therapy. The goal of this project was to identify and evaluate such sustained release, in situ formulations that can help achieve prolonged exposure of protein therapeutics with a short systemic half-life. Natural polymers were used to develop injectable, thermosensitive in situ hydrogels and single-chain variable fragment (scFv) of trastuzumab was used as the model protein with a short half-life. The three polymer combinations tested were: (1) Chitosan and β-glycerophosphate, (2) Chitosan, β-glycerophosphate, and Hyaluronic Acid, and (3) Hyaluronic Acid and Dextran. In vitro drug release experiments were conducted, using different combinations of various polymer concentrations and different drug loading amounts, to identify optimal combinations with prolonged and controlled drug release while exhibiting minimal burst release effect. Select formulations were injected subcutaneously in normal mice to evaluate the pharmacokinetics of scFv for 14 days and identify drug release kinetics in vivo. A two-compartment PK model was also established to quantitatively characterize the release kinetics and disposition of scFv following in vivo administration of the hydrogels. The scFv was undetectable in plasma after 4 and 24 hours following intravenous and subcutaneous administration, respectively. However, all three hydrogel systems were found to provide controlled release of scFv in vivo and maintain detectable concentrations of scFv for at least 14 days. The results suggested that subcutaneous injection of thermosensitive in situ hydrogels may be used to achieve sustained exposure of protein therapeutics which have a very short half-life and thus require frequent administration.

Injectable hybrid hydrogels physically crosslinked based on carrageenan and green graphene for tissue repair

Injectable and biocompatible novel hybrid hydrogels based on physically crosslinked natural biopolymers and green graphene for potential use in tissue engineering are reported. Kappa and iota carrageenan, locust bean gum and gelatin are used as biopolymeric matrix. The effect of green graphene content on the swelling behavior, mechanical properties and biocompatibility of the hybrid hydrogels is investigated. The hybrid hydrogels present a porous network with three-dimensionally interconnected microstructures, with lower pore size than that of the hydrogel without graphene. The addition of graphene into the biopolymeric network improves the stability and the mechanical properties of the hydrogels in phosphate buffer saline solution at 37 °C without noticeable change in the injectability. The mechanical properties of the hybrid hydrogels were enhanced by varying the dosage of graphene between 0.025 and 0.075 w/v%. In this range, the hybrid hydrogels preserve their integrity during mechanical test and recover the initial shape after removing the applied stress. Meanwhile, hybrid hydrogels with graphene content of up to 0.05 w/v% exhibit good biocompatibility for 3T3-L1 fibroblasts; the cells proliferate inside the gel structure and show higher spreading after 48 h. These injectable hybrid hydrogels with graphene have promising future as materials for tissue repair.

Graphene Oxide-Carbamoylated Chitosan Hydrogels with Tunable Mechanical Properties for Biological Applications

Chitosan (CH)-based hydrogels have been extensively researched in numerous biological applications, including drug delivery, biosensing, wound healing, and tissue engineering, to name a few. Previously, modified CH hydrogels by carbamoylation, using potassium cyanate (KCNO) as the cross-linker, have shown improvement in viscoelastic properties and biocompatibility. In this study, graphene oxide (GO) nanofillers are added to carbamoylated CH to form a nanocomposite hydrogel and study the influence of CH molecular weight (M_w) and GO loading concentrations on hydrogel properties. The physical properties (swelling, degradation, and porous structure) of the hydrogels can be tuned as required for cell attachment and spreading by varying both the GO concentration and the M_w of CH. Rheological characterization showed an improvement in the mechanical properties (storage modulus, yield stress, and viscosity) of the synthesized CH-GO hydrogels with an increase in the M_w of CH and the GO concentration. Human retinal pigmented epithelial-1 (RPE-1) cells seeded onto the prepared hydrogel scaffolds showed good cell viability, adhesion, and cell spreading, confirming their cytocompatibility, with dependence on both M_w of CH and GO loading.

Graphene Oxide/Chitosan Injectable Composite Hydrogel for Controlled Release of Doxorubicin: An Approach for Enhanced Intratumoral Delivery

Intratumoral (IT) injection of chemotherapeutics into needle-accessible solid tumors can directly localize the anticancer drug in the tumor site, thus increasing its local bioavailability and reducing its undesirable effects compared to systemic administration. In this study, graphene oxide (GO)-based chitosan/β-glycerophosphate (CS/GP) thermosensitive injectable composite hydrogels (CH) were prepared and optimized for the localized controlled delivery of doxorubicin (DOX). A quality-by-design (QbD) approach was used to study the individual and combined effects of several formulation variables to produce optimal DOX-loaded GO/CS/GP CH with predetermined characteristics, including gelation time, injectability, porosity, and swelling capacity. The surface morphology of the optimal formulation (DOX/opt CH), chemical interaction between its ingredients and in vitro release of DOX in comparison to GO-free CS/GP CH were investigated. Cell viability and cellular uptake after treatment with DOX/opt CH were studied on MCF 7, MDB-MB-231 and FaDu cell lines. The statistical analysis of the measured responses revealed significant effects of the concentration of GO, the concentration of CS, and the CS:GP ratio on the physicochemical characteristics of the prepared GO/CS/GP CH. The optimization process showed that DOX-loaded GO/CS/GP CH prepared using 0.1% GO and 1.7% CS at a CS: GO ratio of 3:1 (v/v) had the highest desirability value. DOX/opt CH showed a porous microstructure and chemical compatibility between its ingredients. The incorporation of GO resulted in an increase in the ability of the CH matrices to control DOX release in vitro. Finally, cellular characterization showed a time-dependent increase in cytotoxicity and cellular uptake of DOX after treatment with DOX/opt CH. The proposed DOX/opt CH might be considered a promising injectable platform to control the release and increase the local bioavailability of chemotherapeutics in the treatment of solid tumors.

MicroRNA-29b/graphene oxide–polyethyleneglycol–polyethylenimine complex incorporated within chitosan hydrogel promotes osteogenesis

MicroRNAs (miRNAs) play a pivotal role in regulating a number of physiologic and pathologic processes including bone marrow mesenchymal stem cell (BMSC) osteogenic differentiation, making them a candidate used to promote osteogenesis. However, due to intrinsic structure and characteristics, “naked” miRNAs are unstable in serum and could not pass across the cellular membrane. Nano delivery systems seem to be a solution to these issues. Recently, graphene oxide (GO)-based nanomaterials are considered to be promising for gene delivery due to their unique physiochemical characteristics such as high surface area, biocompatibility, and easy modification. In this work, a GO-based nanocomplex functionalized by polyethyleneglycol (PEG) and polyethylenimine (PEI) was prepared for loading and delivering miR-29b, which participates in multiple steps of bone formation. The nanocomplex revealed good biocompatibility, miRNA loading capacity, and transfection efficiency. The miR-29b/GO-PEG-PEI nanocomplex was capsulated into chitosan (CS) hydrogel for osteogenesis. In vitro and in vivo evaluation indicated that miR-29b/GO-PEG-PEI@CS composite hydrogel was able to promote BMSC osteogenic differentiation and bone regeneration. All these results indicate that PEG/PEI functionalized GO could serve as a promising candidate for miRNA cellular delivery, and the miR-29b/GO-PEG-PEI@CS hydrogel has the potential for repairing bone defects in vivo.

Application of Graphene Oxide-Based Hydrogels in Bone Tissue Engineering

As an important derivative of graphene-based materials, graphene oxide (GO) not only plays an important role not only in optoelectronics and sensing but also in biology due to its unique mechanical, electronic, and optical properties. This article reviews the application of GO-based hydrogels in bone tissue engineering. Whether it is a hydrogel synthesized with natural polymer compounds, synthetic polymer chemicals, bioceramics, bioactive factors, or other materials, the addition of GO can significantly improve various properties of the hydrogel. We also introduce some high-performance GO-based hydrogels in this paper, proposing some insights into materials that may be applied to bone tissue engineering in the future.

Analysis of clinical trials on biomaterial and therapeutic applications of chitosan: A review

Chitosan is a modified natural carbohydrate polymer derived from chitin that occurs in many natural sources. It has a diverse range of applications in medical and pharmaceutical sciences. Its primary and permitted use is biomaterial in medical devices. Chitosan and its derivatives also find utility in pharmaceuticals as an excipient, drug carrier, or therapeutic agent. The USFDA has approved chitosan usage as a biomaterial but not for pharmaceutical use, primarily because of the concerns over its source, purity, and immunogenicity. A large number of clinical studies are underway on chitosan-based materials/ products because of their diverse applications. Herein, we analyze clinical studies to understand their clinical usage portfolio. Our analysis shows that >100 clinical studies are underway to investigate the safety/efficacy of chitosan or its biomaterials/ nanoparticles, comprising ~95% interventional and ~ 5% observational studies. The regulatory considerations that limit the use of chitosan in pharmaceuticals are also deliberated. TEASER: Clinical Trials of Chitosan.

Evaluation of graphene-derived bone scaffold exposure to the calvarial bone_in-vitro and in-vivo studies

Graphene is a novel material which has recently been gaining great interest in the biomedical fields. Our previous study observed that graphene-derived particles help induce bone formation in a murine calvarial model. Here, we further developed a blended graphene-contained polycaprolactone (PCL/G) filament for application in a 3D-printed bone scaffold. Since implants are expected to be for long-term usage, in vitro cell culture and in vivo scaffold implants were evaluated in a critical-size bone defect calvarial model for over 60 weeks. Graphene greatly improved the mechanical strength by 30.2% compared to pure PCL. The fabricated PCL/G scaffolds also showed fine cell viability. In animal model, an abnormal electroencephalogram power spectrum and early signs of aging, such as hair graying and hair loss, were found in the group with a PCL/G scaffold compared to pure PCL scaffold. Neither of the abnormal symptoms caused death of all animals in both groups. The long-term use of graphene-derived biomaterials for in-vivo implants seems to be safe. But the comprehensive biosafety still needs further evaluation.

Injectable nanocomposite hydrogels as an emerging platform for biomedical applications: A review

Hydrogels have attracted much attention for biomedical and pharmaceutical applications due to the similarity of their biomimetic structure to the extracellular matrix of natural living tissues, tunable soft porous microarchitecture, superb biomechanical properties, proper biocompatibility, etc. Injectable hydrogels are an exciting type of hydrogels that can be easily injected into the target sites using needles or catheters in a minimally invasive manner. The more comfortable use, less pain, faster recovery period, lower costs, and fewer side effects make injectable hydrogels more attractive to both patients and clinicians in comparison to non-injectable hydrogels. However, it is difficult to achieve an ideal injectable hydrogel using just a single material (i.e., polymer). This challenge can be overcome by incorporating nanofillers into the polymeric matrix to engineer injectable nanocomposite hydrogels with combined or synergistic properties gained from the constituents. This work aims to critically review injectable nanocomposite hydrogels, their preparation methods, properties, functionalities, and versatile biomedical and pharmaceutical applications such as tissue engineering, drug delivery, and cancer labeling and therapy. The most common natural and synthetic polymers as matrices together with the most popular nanomaterials as reinforcements, including nanoceramics, carbon-based nanostructures, metallic nanomaterials, and various nanosized polymeric materials, are highlighted in this review.

Evaluation of an Injectable Hydrogel Based on Hyaluronic Acid-chitosan/β-glycerophosphate-loaded Mesenchymal Stem Cells in Enhancing the Therapeutic Efficacy of Myocardial Infarction

Myocardial infarction (MI), which is due to cardiac dysfunction, results in morbidity and mortality. Moreover, the cellular activity of transplanted mesenchymal stem cells (MSCs)generally limits their therapeutic efficacy in the treatment of MI. Here, inject able hyaluronic acid-chitosan/β-glycerophosphate (HA-CS/β-GP) hydrogel-loaded MSCs were prepared, after which their effects on the treatment of MI were investigated. The synthesized HA-CS/β-GP hydrogels exhibited swelling ratio (SR), an in vitro degradation value, and a gelatin time of 82.19 ± 4.1, 88.18% ± 2.4%, and 9 s, respectively. Further, rheological studies revealed that the elastic modulus of the HA-CS/β-GP hydrogels was ≥230 Pa, exhibiting large elastic to viscous modulus ratio, which indicated their mechanical strength. Furthermore, the in vitro 3T3 cell and MSC culture studies confirmed the good biocompatibility of the HA-CS and HA-CS/β-GP hydrogels. The implantation of the synthesized hydrogels in the mouse MI model considerably improved the therapeutic effect of the MSCs (enhanced cardiac function, reduced cardiomyocyte apoptosis, and increased vascularization) for the first time. The innovative synergistic strategy of combining injectable HA-CS and HA-CS/β-GP hydro gels with MSCs might be suitable for the effective treatment of cardiac morbidity due to MIs. This article is protected by copyright. All rights reserved.

Evaluation of Inflammatory Response Due to Use of Controlled Release Drug Delivery System of Chitosan Hydrogel Loaded with Buprenorphine and Ketorolac in Rat with Experimental Proximal Tibial Epiphysis Defect

Aims:A controlled release drug delivery system loaded with buprenorphine and ketorolac was synthesized and used in the experimental model of bone defect and while evaluating the inflammatory response, the repair process in the defects was investigated.Materials and methods:To determine the effectiveness of the synthesized the mentioned systems, 5 groups were defined; the control group, the chitosan hydrogel receiving group (chitosan group), the ketorolac-loaded chitosan hydrogel group (ketorolac group), the buprenorphine-loaded chitosan hydrogel receiving group (buprenorphine group), and the chitosan hydrogel-loading group loaded with a combination of ketorolac and buprenorphine (ketorolac-buprenorphine group).Results:The results showed that the population of leukocytes (tWBC) and neutrophils on different days of the study in the control group compared to other groups had a significant increase (P < 0.05) while on day 7 of the study in the ketorolac group these parameters decreased significantly compared to other groups (P < 0.05). While examining the histological changes in the experimental defect created in the proximal tibia of rats at different times, some inflammatory indices such as total and differential leukocyte population, plasma concentrations of TNF-α and IL-6 were compared in different groups (P < 0.05). The various evaluated data showed that among the different groups, in the control and ketorolac-buprenorphine groups, there was the lowest and highest control of inflammatory response and bone repair, respectively.Conclusion:In the ketorolac group due to the impact of ketorolac on leukocyte populations the best bone healing can be expected among the different treatment groups.

Fabrication of Injectable Chitosan-Chondroitin Sulfate Hydrogel Embedding Kartogenin-Loaded Microspheres as an Ultrasound-Triggered Drug Delivery System for Cartilage Tissue Engineering

Ultrasound-responsive microspheres (MPs) derived from natural polysaccharides and injectable hydrogels have been widely investigated as a biocompatible, biodegradable, and controllable drug delivery system and cell scaffolds for tissue engineering. In this study, kartogenin (KGN) loaded poly (lactide-co-glycolic acid) (PLGA) MPs (MPs@KGN) were fabricated by premix membrane emulsification (PME) method which were sonicated by an ultrasound transducer. Furthermore, carboxymethyl chitosan-oxidized chondroitin sulfate (CMC-OCS) hydrogel were prepared via the Schiff’ base reaction-embedded MPs to produce a CMC-OCS/MPs scaffold. In the current work, morphology, mechanical property, porosity determination, swelling property, in vitro degradation, KGN release from scaffolds, cytotoxicity, and cell bioactivity were investigated. The results showed that MPs presented an obvious collapse after ultrasound treatment. The embedded PLGA MPs could enhance the compressive elastic modulus of soft CMC-OCS hydrogel. The cumulative release KGN from MPs exhibited a slow rate which would display an appropriate collapse after ultrasound, allowing KGN to maintain a continuous concentration for at least 28 days. Moreover, the composite CMC-OCS@MPs scaffolds exhibited faster gelation, lower swelling ratio, and lower in vitro degradation. CCK-8 and LIVE/DEAD staining showed these scaffolds did not influence rabbit bone marrow mesenchymal stem cells (rBMMSCs) proliferation. Then these scaffolds were cultured with rBMMSCs for 2 weeks, and the immunofluorescent staining of collagen II (COL-2) showed that CMC-OCS hydrogel embedded with MPs@KGN (CMC-OCS@MPs@KGN) with ultrasound had the ability to increase the COL-2 synthesis. Overall, due to the improved mechanical property and the ability of sustained KGN release, this injectable hydrogel with ultrasound-responsive property is a promising system for cartilage tissue engineering.

Influence of Charge and Heat on the Mechanical Properties of Scaffolds from Ionic Complexation of Chitosan and Carboxymethyl Cellulose

As one of the most abundant, multifunctional biological polymers, polysaccharides are considered promising materials to prepare tissue engineering scaffolds. When properly designed, wetted porous scaffolds can have biomechanics similar to living tissue and provide suitable fluid transport, both of which are key features for in vitro and in vivo tissue growth. They can further mimic the components and function of glycosaminoglycans found in the extracellular matrix of tissues. In this study, we investigate scaffolds formed by charge complexation between anionic carboxymethyl cellulose and cationic protonated chitosan under well-controlled conditions. Freeze-drying and dehydrothermal heat treatment were then used to obtain porous materials with exceptional, unprecendent mechanical properties and dimensional long-term stability in cell growth media. We investigated how complexation conditions, charge ratio, and heat treatment significantly influence the resulting fluid uptake and biomechanics. Surprisingly, materials with high compressive strength, high elastic modulus, and significant shape recovery are obtained under certain conditions. We address this mostly to a balanced charge ratio and the formation of covalent amide bonds between the polymers without the use of additional cross-linkers. The scaffolds promoted clustered cell adhesion and showed no cytotoxic effects as assessed by cell viability assay and live/dead staining with human adipose tissue-derived mesenchymal stem cells. We suggest that similar scaffolds or biomaterials comprising other polysaccharides have a large potential for cartilage tissue engineering and that elucidating the reason for the observed peculiar biomechanics can stimulate further research.

Thermosensitive Chitosan-β-Glycerophosphate Hydrogels as Targeted Drug Delivery Systems: An Overview on Preparation and Their Applications

Today, with the advances in technology and science, more advanced drug delivery formulations are required. One of these new systems is an intelligent hydrogel. These systems are affected by the environment or conditions that become a gel, stay in the circumstance for a certain period, and slowly release the drug. As an advantage, only a lower dose of the drug is required, and it provides less toxicity and minor damage to other tissues. Hydrogels are of different types, including temperature-sensitive, pH-sensitive, ion change-sensitive, and magnetic field-sensitive. In this study, we investigated a kind of temperature-sensitive smart hydrogel, which has a liquid form at room temperature and becomes gel with increasing temperature. Chitosan-β-glycerophosphate hydrogels have been researched and used in many studies. This study investigates the various factors that influence the gelation mechanism, such as gel formation rates, temperature, pH, time, and gel specificity. Hydrogels are used in many drug delivery systems and diseases, including nasal drug delivery, vaginal drug delivery, wound healing, peritoneal adhesion, ophthalmic drug delivery, tissue engineering, and peptide and protein delivery. Overall, the chitosan-β-glycerophosphate hydrogel is a suitable drug carrier for a wide range of drugs. It shows little toxicity to the body, is biodegradable, and is compatible with other organs. This system can be used in different conditions and different medication ways, such as oral, nasal, and injection.

Intra-Articular Dual Drug Delivery for Synergistic Rheumatoid Arthritis Treatment

Systemic rheumatoid arthritis (RA) regimens fail to attain effective drug level at the affected joints and are associated with serious side effects. Herein, an attempt made to improve therapeutic outcomes of both leflunomide (LEF) which is a disease modifying antirheumatic and dexamethasone (Dex) through local delivery of combination therapy by intra-articular route. LEF and Dex were encapsulated in nanostructured lipid carriers (NLCs) and PLGA nanoparticles (NPs), respectively. Both nanocarriers were loaded into chitosan/β glycerophosphate (CS/βGP) thermo-sensitive hydrogels and injected intra-articularly in adjuvant induced RA rat model. Particle size of LEF NLCs and selected Dex NPs formulations were 200 and 119 nm, respectively. Dex NPs and LEF NLCs showed a sustained release profile for up to 58 and 17 days, respectively. After 14 days of treatment remarkable joint healing was observed for groups treated with Dex NPs in combination with either free LEF or LEF NLCs in CS/βGP hydrogel. Joint diameter measurements, TNF α levels and histopathological examination of dissected joints showed comparable values to the negative control group. This might be attributed to the synergistic effect of drug combination besides the ability of nanocarriers loaded hydrogel to prolong joint residence time and enhance joint healing potential.

Extrusion-Printing of Multi-Channeled Two-Component Hydrogel Constructs from Gelatinous Peptides and Anhydride-Containing Oligomers

The performance of artificial nerve guidance conduits (NGC) in peripheral nerve regeneration can be improved by providing structures with multiple small channels instead of a single wide lumen. 3D-printing is a strategy to access such multi-channeled structures in a defined and reproducible way. This study explores extrusion-based 3D-printing of two-component hydrogels from a single cartridge printhead into multi-channeled structures under aseptic conditions. The gels are based on a platform of synthetic, anhydride-containing oligomers for cross-linking of gelatinous peptides. Stable constructs with continuous small channels and a variety of footprints and sizes were successfully generated from formulations containing either an organic or inorganic gelation base. The adjustability of the system was investigated by varying the cross-linking oligomer and substituting the gelation bases controlling the cross-linking kinetics. Formulations with organic N-methyl-piperidin-3-ol and inorganic K₂HPO₄ yielded hydrogels with comparable properties after manual processing and extrusion-based 3D-printing. The slower reaction kinetics of formulations with K₂HPO₄ can be beneficial for extending the time frame for printing. The two-component hydrogels displayed both slow hydrolytic and activity-dependent enzymatic degradability. Together with satisfying in vitro cell proliferation data, these results indicate the suitability of our cross-linked hydrogels as multi-channeled NGC for enhanced peripheral nerve regeneration.

Stimuli-responsive biomaterials for cardiac tissue engineering and dynamic mechanobiology

Since the term "smart materials" was put forward in the 1980s, stimuli-responsive biomaterials have been used as powerful tools in tissue engineering, mechanobiology, and clinical applications. For the purpose of myocardial repair and regeneration, stimuli-responsive biomaterials are employed to fabricate hydrogels and nanoparticles for targeted delivery of therapeutic drugs and cells, which have been proved to alleviate disease progression and enhance tissue regeneration. By reproducing the sophisticated and dynamic microenvironment of the native heart, stimuli-responsive biomaterials have also been used to engineer dynamic culture systems to understand how cardiac cells and tissues respond to progressive changes in extracellular microenvironments, enabling the investigation of dynamic cell mechanobiology. Here, we provide an overview of stimuli-responsive biomaterials used in cardiovascular research applications, with a specific focus on cardiac tissue engineering and dynamic cell mechanobiology. We also discuss how these smart materials can be utilized to mimic the dynamic microenvironment during heart development, which might provide an opportunity to reveal the fundamental mechanisms of cardiomyogenesis and cardiac maturation.

Promising Drug Delivery Approaches to Treat Microbial Infections in the Vagina: A Recent Update

An optimal host-microbiota interaction in the human vagina governs the reproductive health status of a woman. The marked depletion in the beneficial Lactobacillus sp. increases the risk of infection with sexually transmitted pathogens, resulting in gynaecological issues. Vaginal infections that are becoming increasingly prevalent, especially among women of reproductive age, require an effective concentration of antimicrobial drugs at the infectious sites for complete disease eradication. Thus, topical treatment is recommended as it allows direct therapeutic action, reduced drug doses and side effects, and self-insertion. However, the alterations in the physiological conditions of the vagina affect the effectiveness of vaginal drug delivery considerably. Conventional vaginal dosage forms are often linked to low retention time in the vagina and discomfort which significantly reduces patient compliance. The lack of optimal prevention and treatment approaches have contributed to the unacceptably high rate of recurrence for vaginal diseases. To combat these limitations, several novel approaches including nano-systems, mucoadhesive polymeric systems, and stimuli-responsive systems have been developed in recent years. This review discusses and summarises the recent research progress of these novel approaches for vaginal drug delivery against various vaginal diseases. An overview of the concept and challenges of vaginal infections, anatomy and physiology of the vagina, and barriers to vaginal drug delivery are also addressed.

Injectable Thermosensitive Chitosan/Pullulan-Based Hydrogels with Improved Mechanical Properties and Swelling Capacity

Thermosensitive chitosan/β-glycerophosphate (CS/BGP) systems have been developed as injectable hydrogels. However, the hydrogels exhibited poor mechanical properties due to their physically crosslinked networks. In this work, CS/BGP hydrogels were reinforced by covalent crosslinking using genipin (GE) and concomitantly semi-interpenetrating networks using pullulan (PL). Based on response surface methodology, the optimized formulation was composed of CS (1.05%, w/v), PL (1%, w/v), BGP (6%, w/v), and GE (70.79 mcg/mL). The optimized hydrogels exhibited Young's modulus of 92.65 ± 4.13 kPa and a percentage of equilibrium swelling ratio of 3259.09% ± 58.90%. Scanning electron micrographs revealed a highly porous structure with nanofibrous networks in the CS/PL/BGP/GE hydrogels. The chemical interactions between the compositions were investigated by Fourier-transform infrared spectroscopy. Rheological measurements illustrated that the optimized hydrogels displayed sol-gel transition within one minute at 37 °C, a lower critical solution temperature of about 31 °C, and viscoelastic behavior with high storage modulus. Furthermore, the optimized hydrogels demonstrated higher resistance to in vitro enzymatic degradation, compared to the hydrogels without GE. Our findings could suggest that the thermosensitive CS/PL/BGP/GE hydrogels with enhanced mechanical properties and swelling capacity demonstrate the potential for use as scaffolds and carriers for cartilage tissue engineering and drug delivery applications.

Effects of beta-tricalcium phosphate nanoparticles on the properties of a thermosensitive chitosan/collagen hydrogel and controlled release of quercetin

In the present study, an inorganic matrix of beta-tricalcium phosphate (bTCP) nanoparticles and quercetin was incorporated into an organic matrix of 2:1 (w/w) chitosan/collagen composite to fabricate thermosensitive bTCP-chitosan/collagen-quercetin hydrogels. A sol-gel transition of the hydrogels was stimulated by beta-glycerophosphate (bGP) and temperature changes at physiological temperature and pH levels. Thereafter, the effects of 1%-3% (w/v) bTCP on properties of the bTCP-bGP-2:1 (w/w) chitosan/collagen hydrogels were investigated. Notably, the incorporation of 1%-3% (w/v) bTCP in the hydrogels did not interfere with the gelation process and time of the hydrogels at physiological temperature and pH levels. The bTCP-hydrogels exhibited a porous structure, interconnecting pore architecture, and median pore size of 100-200 μm. The incorporation of 3% bTCP increased the mechanical strength but decreased the swelling and degradation rates, pore size, permeability, and quercetin release rate of the hydrogels. The hydrogels were noncytotoxic and able to support cell encapsulation. A sustained quercetin release profile of the 3% bTCP-hydrogel further suggested the applicability of the hydrogel as a delivery vehicle of natural flavonoids for bone regeneration.

Thermo-irreversible glycol chitosan/hyaluronic acid blend hydrogel for injectable tissue engineering

Thermogels that undergo temperature-dependent sol-gel transition have recently attracted attention as a promising biomaterial for injectable tissue engineering. However, conventional thermogels usually suffer from poor physical properties and low cell binding affinity, limiting their practical applications. Here, a simple approach for developing a new thermogel with enhanced physical properties and cell binding affinity is proposed. This thermogel (AcHA/HGC) was obtained by simple blending of a new class of polysaccharide-based thermogel, N-hexanoyl glycol chitosan (HGC), with a polysaccharide possessing good cell binding affinity, acetylated hyaluronic acid (AcHA). Gelation of AcHA/HGC was initially triggered by the thermosensitive response of HGC and gradually intensified by additional physical crosslinking mechanisms between HGC and AcHA, resulting in thermo-irreversible gelation. Compared to the thermos-reversible HGC hydrogel, the thermo-irreversible AcHA/HGC hydrogel exhibited enhanced physical stability, mechanical properties, cell binding affinity, and tissue compatibility. These results suggest that our thermo-irreversible hydrogel is a promising biomaterial for injectable tissue engineering.

Preparation and characterization of a novel thermosensitive and bioadhesive cephalexin nanohydrogel: a promising platform for topical antibacterial delivery

OBJECTIVE

Impetigo is a common and highly contagious bacterial skin infection that mostly affects young children and infants. Herein, we report the development of a thermosensitive and bioadhesive in-situ hydrogel-forming system containing cephalexin-loaded nanoparticles (NPs) suitable for antibacterial drug delivery.

METHODS

The nanohydrogel was formulated using drug-loaded NPs and characterized by its physicochemical characteristics. Antibacterial activities of the cephalexin NPs and nanohydrogel were examined in vitro against Staphylococcus aureus (S. aureus). The ex vivo drug permeation study was performed using rat skin. Finally, this formulation was tested for in vivo antibacterial activity using superficial skin infections in rats.

RESULTS

The mean size and entrapment efficiency of the NPs were found to be 178 nm and 58%, respectively. The transmission electron microscopy analysis verified the formation of spherical NPs. The drug-loaded NPs showed an enhanced eradication effect against S. aureus according to the declined MIC values in comparison with the untreated drug. The ex vivo permeation profile of the cephalexin nanohydrogel showed a slow release pattern for 8 h. When applied on rat skin for 6 days, the nanohydrogel exhibited a superior antibacterial activity with normal hair growth and skin appearance as compared to the plain drug hydrogel.

CONCLUSIONS

These findings suggested that the nanohydrogel could serve as a valuable drug delivery platform against superficial bacterial infections.

Processing and modification of hydrogel and its application in emerging contaminant adsorption and in catalyst immobilization: a review

Due to the wonderful property of hydrogels, they can provide a platform for a wide range of applications. Recently, there is a growing research interest in the development of potential hydrogel adsorbents in wastewater treatment due to their adsorption ability toward aqueous pollutants. It is important to prepare such a hydrogel that possesses appropriate robustness, adsorption capacity, and adsorption efficiency to meet the need of water treatment. In order to improve the property of hydrogels, much effort has been made by researchers to modify hydrogels, among which incorporating inorganic components into the polymeric networks is the most common method, which can reduce the product cost and simplify the preparation procedure. Not only can hydrogel be applied as adsorbent, but it also can be used as matrix for catalyst immobilization. In this review, the key advancement on the preparation and modification of hydrogels is discussed, with special emphasis on the introduction of inorganic materials into polymeric networks and consequential changes in the properties of mechanical strength, swelling, and adsorption. Besides, hydrogels used as adsorbents for removal of dyes and inorganic pollutants have been widely explored, but their use for adsorbing emerging contaminants from aqueous solution has not received much attention. Thus, this review is mainly focused on hydrogels' application in removing emerging contaminants by adsorption. Furthermore, hydrogels can be also applied in immobilizing catalysts, such as enzyme and photocatalyst, to remove pollutants completely and avoid secondary pollution, so their progress as catalyst matrix is overviewed.

Low-Molecular-Weight Heparin-Functionalized Chitosan-Chondroitin Sulfate Hydrogels for Controlled Release of TGF-β3 and in vitro Neocartilage Formation

Repair of hyaline cartilage remains a huge challenge in clinic because of the avascular and aneural characteristics and the paucity of endogenous repair cells. Recently, tissue engineering technique, possessing unique capacity of repairing large tissue defects, avoiding donor complications and two-stage invasive surgical procedures, has been developed a promising therapeutic strategy for cartilage injury. In this study, we incorporated low-molecular-weight heparin (LMWH) into carboxymethyl chitosan-oxidized chondroitin sulfate (CMC-OCS) hydrogel for loading transforming growth factor-β3 (TGF-β3) as matrix of peripheral blood mesenchymal stem cells (PB-MSCs) to construct tissue-engineered cartilage. Meanwhile, three control hydrogels with or without LMWH and/or TGF-β3 were also prepared. The gelling time, microstructures, mechanical properties, degradation rate, cytotoxicity, and the release of TGF-β3 of different hydrogels were investigated. In vitro experiments evaluated the tri-lineage differentiation potential of PB-MSCs, combined with the proliferation, distribution, viability, morphology, and chondrogenic differentiation. Compared with non-LMWH-hydrogels, LMWH-hydrogels (LMWH-CMC-OCS-TGF-β3) have shorter gelling time, higher mechanical strength, slower degradation rate and more stable and lasting release of TGF-β3. After two weeks of culture in vitro, expression of cartilage-specific genes collagen type-2 (COL-2) and aggrecan (AGC), and secretion of glycosaminoglycan (GAG), and COL-2 proteins in LMWH-CMC-OCS-TGF-β3 group were significantly higher than those in other groups. COL-2 immunofluorescence staining showed that the proportion of COL-2 positive cells and immunofluorescence intensity in LMWH-CMC-OCS-TGF-β3 hydrogel were significantly higher than those in other groups. The LMWH-CMC-OCS-TGF-β3 hydrogel can slowly release TGF-β3 in a long term, and meanwhile the hydrogel can provide a biocompatible microenvironment for the growth and chondrogenic differentiation of PB-MSCs. Thus, LMWH functionalized CMC-OCS hydrogels proposed in this work will be beneficial for constructing functional scaffolds for tissue-engineered cartilage.