Enhancement of mechanical properties of nanohydrogels based on natural gum with functionalized multiwall carbon nanotube: Study of swelling and drug release

Preparation and antitumor study of intelligent injectable hydrogel: Carboxymethyl chitosan-aldehyde gum Arabic composite graphene oxide hydrogel

In this study, we used polyaldehyde gum Arabic (OGA) and carboxymethyl chitosan (CMCS) as a gel matrix to form an injectable self-healing hydrogel by Schiff-base bonding. Further, graphene oxide (GO) was loaded with doxorubicin (DOX) to the hydrogel, which resulted in a CMCS-OGA/GO@DOX hydrogel. We achieved a DOX drug loading capacity of 43.80 ± 1.13 %. Rheological studies showed that GO hydrogels have improved mechanical properties. The in vitro release profile showed pH responsiveness with 88.21 % DOX release at pH 5.5. Biocompatibility studies showed that the hydrogel composition had good cytocompatibility with L929 cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed a cell survival rate of 93.88 % within 48 h. The DOX-loaded hydrogel exhibited higher cell mortality in breast cancer cells (4 T1), with an inhibition rate of 79.4 % at 48 h. Acridine orange/ethidium bromide staining experiments on 4 T1 cells showed that when loaded with the same DOX concentration, the hydrogel significantly reduced the toxic effects on normal cells, whereas it had significant cytotoxic effects on cancer cells. This result indicates that the prepared GO hydrogel drug delivery system can serve as a novel approach for localized breast cancer treatment.

Fabrication and evaluation of antimicrobial cellulose/Arabic gum hydrogels as potential drug delivery vehicle

This article aims to assess the highly potent antimicrobial hydrogels composed of cellulose and Arabic gum containing sulfadiazine drug (sulfadiazine-loaded Cel/AG) as drug-targeting carriers. ATR-IR, SEM/ EDS, XRD, and XPS methods were used to investigate the hydrogel. The highest water absorption % was 489.93 ± 4.5 at pH 7.4. Pseudo-second order and Fickian diffusion govern the swelling behavior. The maximal sulfadiazine loading percent was 82.291 ± 74. The in-vitro drug release exhibited significant responses in physiologically simulated pH values. The maximum cumulative release percent was 66.42 ± 0.6 % at pH 7.4. The drug release is predicted by the first order and Korsmeyer-Peppas models. The first diffusion coefficient was (D_i = 9.207 ± 47 × 10^-3 cm²/h) and the late one was (D_L = 5.64 ± 9.0 × 10^-2 cm²/h) at pH 7.4. That hydrogel is well-thought-out a potential drug delivery vehicle. The thermal stability of the Cel/AG hydrogel drug carrier has been enhanced by the incorporation of sulfadiazine which is evidenced by increasing the total activation approximately two-fold. The total activation energy of Cel/AG and sulfadiazine-loaded Cel/AG hydrogels were -0.07362 and -0.2092 J/mol. The sulfadiazine medication's inhibitory effect was markedly enhanced when it was incorporated into the Cel/AG hydrogel films.

Al3+/Ca2+ cross-linked hydrogel matrix tablet of etherified tara gum for sustained delivery of tramadol hydrochloride in gastrointestinal milieu

Tara gum (TG) was derivatized to carboxymethyl TG (CMTG) and then cross-linked with Al³⁺/Ca²⁺ ions to prepare Al/Ca cross-linked CMTG matrices for sustained delivery of Tramadol Hydrochloride (TH), a highly water-soluble drug. The effect of Al³⁺/Ca²⁺ ions concentration on swelling, erosion, and drug release behavior from Al/Ca-CMTG matrices was investigated. Al-CMTG matrices had greater cross-linking density, produced a more rigid and denser hydrogel layer than Ca-CMTG matrices. The rate of swelling, erosion, and in vitro drug release from Al-CMTG matrices was slower than from Ca-CMTG matrices. The most important finding of our study indicated that at the same concentration of cross-linking ions, the release of TH from Al-CMTG matrices was slower compared to Ca-CMTG matrices. The optimized formulation containing 9 % w/w AlCl₃ in CMTG matrices released TH in a sustained manner up to 12 h in the gastrointestinal milieu. Moreover, it was observed that the prepared optimized formulation exhibited a more sustained release of TH compared to the marketed product.

Highly Responsive Chitosan-Co-Poly (MAA) Nanomatrices through Cross-Linking Polymerization for Solubility Improvement

In this study, we report the highly responsive chitosan-based chemically cross-linked nanomatrices, a nano-version of hydrogels developed through modified polymerization reaction for solubility improvement of poorly soluble drug simvastatin. The developed nanomatrices were characterized for solubilization efficiency, swelling studies, sol-gel analysis, in vitro drug release studies, DSC, FTIR, XRD, SEM, particle size analysis, and stability studies. An in vivo acute toxicity study was conducted on female Winstor rats, the result of which endorsed the safety and biocompatibility of the system. A porous and fluffy structure was observed under SEM analysis, which supports the great swelling tendency of the system that further governs the in vitro drug release. Zeta sizer analyzed the particle size in the range of 227.8 ± 17.8 nm. Nano sizing and grafting of hydrophilic excipients to the nanomatrices system explains this shift of trend towards the enhancement of solubilization efficiency, and, furthermore, the XRD results confirmed the amorphous nature of the system. FTIR and DSC analysis confirmed the successful grafting and stability to the system. The developed nanomatrices enhanced the release characteristics and solubility of simvastatin significantly and could be an effective technique for solubility and bioavailability enhancement of other BCS class-II drugs. Due to enhanced solubility, efficient method of preparation, excellent physico-chemical features, and rapid and high dissolution and bio-compatibility, the developed nanomatrices may be a promising approach for oral delivery of hydrophobic drugs.

Recent advances in guar gum based drug delivery systems and their administrative routes

Guar gum-based drug carrier systems have gained attention for the delivery of various therapeutic agents via different administration routes for attaining controlled and sustained release. Guar gum offers a safe and effective system for drug delivery due to its natural occurrence, easy availability, biocompatibility, and biodegradability, besides simple and mild preparation techniques. Furthermore, the possibility of using various routes such as oral, buccal, transdermal, intravenous, and gene delivery further diversify guar gum applications in the biomedical field. This review delineates the recent investigation on guar gum-based drug carrier systems like hydrogels, nanoparticles, nanocomposites, and scaffolds along with their related delivery routes. Also, the inclusion of data of the loading and subsequent release of the drugs enables to explore the noble and improved drug targeting therapies.

Electrospun Scaffold with Sustained Antibacterial and Tissue-Matched Mechanical Properties for Potential Application as Functional Mesh

Introduction

Various materials and approaches have been used to reduce the mesh-induced inflammatory response and modify the mesh with tissue-matched mechanical properties, aiming to improve the repair of abdominal wall defects.

Materials and Methods

In this study, we fabricated a polycaprolactone (PCL)/silk fibroin (SF) mesh integrated with amoxicillin (AMX)-incorporating multiwalled carbon nanotubes (MWCNTs) via electrospinning, grafting and crosslinking, developing a sustainable antibiotic and flexible mesh. AMX was loaded into the hollow tubular MWCNTs by physical adsorption, and a nanofibrous structure was constructed by electrospinning PCL and SF (40:60 w/w). The AMX@MWCNTs were then chemically grafted onto the surfaces of the PCL/SF nanofibers by treating with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) solution for simultaneous crosslinking and coating. The incorporation of AMX into the MWCNTs (AMX@MWCNTs) and the integration of the AMX@MWCNTs with the PCL/SF nanofibers were characterized. Then, the functional mesh was fabricated and fully evaluated in terms of antibacterial activity, mechanical properties and host response.

Results

Our results demonstrated that the PCL/SF nanofibrous structure was fabricated successfully by electrospinning. After integrating with AMX@MWCNT by grafting and crosslinking, the functional mesh showed undeformed structure, modified surface hydrophilicity and biocompatible interfaces, abdominal wall-matched mechanical properties, and a sustained-release antibiotic profile in E. coli growth inhibition compared to those of PCL/SF mesh in vitro. In a rat model with subcutaneous implantation, the functional mesh incited less mesh-induced inflammatory and foreign body responses than PCL/SF mesh within 14 days. The histological analysis revealed less infiltration of granulocytes and macrophages during this period, resulting in the loosely packed collagen deposition on the functional mesh and prominent collagen incorporation.

Discussion

Therefore, this designed PCL/SF-AMX@MWCNT nanofibrous mesh, functionalized with antibacterial and tissue-matched mechanical properties, provides a promising alternative for the repair of abdominal wall defects.

Recent Advances in Natural Gum-Based Biomaterials for Tissue Engineering and Regenerative Medicine: A Review

The engineering of tissues under a three-dimensional (3D) microenvironment is a great challenge and needs a suitable supporting biomaterial-based scaffold that may facilitate cell attachment, spreading, proliferation, migration, and differentiation for proper tissue regeneration or organ reconstruction. Polysaccharides as natural polymers promise great potential in the preparation of a three-dimensional artificial extracellular matrix (ECM) (i.e., hydrogel) via various processing methods and conditions. Natural polymers, especially gums, based upon hydrogel systems, provide similarities largely with the native ECM and excellent biological response. Here, we review the origin and physico-chemical characteristics of potentially used natural gums. In addition, various forms of scaffolds (e.g., nanofibrous, 3D printed-constructs) based on gums and their efficacy in 3D cell culture and various tissue regenerations such as bone, osteoarthritis and cartilage, skin/wound, retinal, neural, and other tissues are discussed. Finally, the advantages and limitations of natural gums are precisely described for future perspectives in tissue engineering and regenerative medicine in the concluding remarks.

Antimicrobial gum bio-based nanocomposites and their industrial and biomedical applications

Gum polysaccharides are derived from renewable sources. They are readily available, inexpensive, non-hazardous and eco-friendly. Depending upon the source, gums may be categorized as microbial gums, plant exudate gums or seed gums. Naturally occurring gum carbohydrates find multiple applications in the biomedical arena, compared with synthetic compounds, because of their unique structures and functionalities. Gums and their biocomposites are preferred for sustained drug delivery because they are safe and edible as well as more susceptible to biodegradation. The present review provides a state-of-the-art conspectus on the industrial and biomedical applications of antimicrobial gum-based biocomposites. Different kinds of gums polysaccharides will first be addressed based on their sources. Metal-, carbon- and organic-based nanostructures that are used in gum nanocomposites will then be reviewed with respect to their industrial and biomedical applications, to provide a backdrop for future research.

Ultrasonic-assisted manufacturing of new hydrogel nanocomposite biosorbent containing calcium carbonate nanoparticles and tragacanth gum for removal of heavy metal

This article reports the first incorporation of calcium carbonate nanoparticles (CC NPs) into tragacanth gum (TG) to prepare a new hydrogel nanocomposite (HNC) system using a green, safe, and eco-friendly method, ultrasound irradiation as an efficient biosorbent of heavy metal ions from wastewater. Morphological studies revealed that the surface of obtained HNCs is rough, homogeneous, and porous-like due to the embedding of CC NPs as well as sonication in comparison to the neat TG which has a smooth surface. The particle size reduction was observed for CC NPs in the matrix (from 57 to 10 nm), which is owing to the extraordinary effect of sonication on this process. Thermal stability of HNCs has been increased after using CC NPs from 8.5 wt% for TG to about 22 wt% for HNCs. The optical band gap of TG/CC HNC 5 wt% calculated to be 4.46 eV which is less than that of CC NPs (5.58 eV) and even TG (6.28 eV) and this result indicated that TG/CC HNC 5 wt% is relatively more conductive than CC NPs and TG. The nitrogen adsorption-desorption disclosed an isotherm type III of Brunauer classification for TG/CC HNC 5 wt% and the surface area has been increased from 0.7 m².g^-1 for TG to 2.3 m².g^-1 for TG/CC HNC 5 wt%. Also, the BET surface area for TG/CC HNC 5 wt% calculated to be 7.8 nm which is classified into mesoporous materials. The Pb²⁺ ions were significantly removed from water using TG/CC HNC 5 wt% and the removal efficiency was determined as 83% at optimized conditions (pH = 5, adsorbent dosage = 0.015 g, time = 3 h, and Pb²⁺ concentration = 70 mg.L^-1).