Fabrication and characterization of cefazolin-loaded nanofibrous mats for the recovery of post-surgical wound

Perspectives of nanofibrous wound dressings based on glucans and galactans - A review

Wound healing is a complex and dynamic process that needs an appropriate environment to overcome infection and inflammation to progress well. Wounds lead to morbidity, mortality, and a significant economic burden, often due to the non-availability of suitable treatments. Hence, this field has lured the attention of researchers and pharmaceutical industries for decades. As a result, the global wound care market is expected to be 27.8 billion USD by 2026 from 19.3 billion USD in 2021, at a compound annual growth rate (CAGR) of 7.6 %. Wound dressings have emerged as an effective treatment to maintain moisture, protect from pathogens, and impede wound healing. However, synthetic polymer-based dressings fail to comprehensively address optimal and quick regeneration requirements. Natural polymers like glucan and galactan-based carbohydrate dressings have received much attention due to their inherent biocompatibility, biodegradability, inexpensiveness, and natural abundance. Also, nanofibrous mesh supports better proliferation and migration of fibroblasts because of their large surface area and similarity to the extracellular matrix (ECM). Thus, nanostructured dressings derived from glucans and galactans (i.e., chitosan, agar/agarose, pullulan, curdlan, carrageenan, etc.) can overcome the limitations associated with traditional wound dressings. However, they require further development pertaining to the wireless determination of wound bed status and its clinical assessment. The present review intends to provide insight into such carbohydrate-based nanofibrous dressings and their prospects, along with some clinical case studies.

Preparation of Isopropyl Acrylamide Grafted Chitosan and Carbon Bionanocomposites for Adsorption of Lead Ion and Methylene Blue

Wastewater, which is rich with heavy elements, dyes, and pesticides, represents one of the most important environmental pollutants. Thus, it has been significant to fabricate environmentally friendly polymers with high adsorption ability for those pollutants. Herein, crosslinked chitosan (C-Cs) was prepared using isopropyl acrylamide and methylene bisacrylamide. Carbon nanoparticles (C-NPs) were also obtained by the treatment of the agricultural wastes, which was used with C-Cs to prepare C-Cs/C-NPs nanocomposite (C-Cs/C-NC). Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and transmission electron microscope (TEM) were used to investigate the prepared adsorbent. C-Cs, C-NPs, and C-Cs/C-NC were used in water treatment for the adsorption of lead ions (Pb⁺²) and methylene blue (MB). The adsorption process occurred by the prepared samples was investigated under different conditions, including contact time, as well as different doses and concentrations of adsorbents. The findings exhibited that the adsorption of Pb⁺² and MB by C-Cs/C-NC was higher than C-Cs and C-NPs. In addition, the kinetic and isotherm models were studied, where the results showed that the adsorption of Pb⁺² and MB by various adsorbents obeys pseudo-second-order and Langmuir isotherms, respectively.

Cefazolin Loaded Oxidized Regenerated Cellulose/Polycaprolactone Bilayered Composite for Use as Potential Antibacterial Dural Substitute

Oxidized regenerated cellulose/polycaprolactone bilayered composite (ORC/PCL bilayered composite) was investigated for use as an antibacterial dural substitute. Cefazolin at the concentrations of 25, 50, 75 and 100 mg/mL was loaded in the ORC/PCL bilayered composite. Microstructure, density, thickness, tensile properties, cefazolin loading content, cefazolin releasing profile and antibacterial activity against S. aureus were measured. It was seen that the change in concentration of cefazolin loading affected the microstructure of the composite on the rough side, but not on the dense or smooth side. Cefazolin loaded ORC/PCL bilayered composite showed greater densities, but lower thickness, compared to those of drug unloaded composite. Tensile modulus was found to be greater and increased with increasing cefazolin loading, but tensile strength and strain at break were lower compared to the drug unloaded composite. In vitro cefazolin release in artificial cerebrospinal fluid (aCSF) consisted of initial burst release on day 1, followed by a constant small release of cefazolin. The antibacterial activity was observed to last for up to 4 days depending on the cefazolin loading. All these results suggested that ORC/PCL bilayered composite could be modified to serve as an antibiotic carrier for potential use as an antibacterial synthetic dura mater.

Synthesis and Characterization of Antibiotic–Loaded Biodegradable Citrate Functionalized Mesoporous Hydroxyapatite Nanocarriers as an Alternative Treatment for Bone Infections

The continuing growth of bacterial resistance makes the top challenge for the healthcare system especially in bone-infections treatment. Current estimates reveal that in 2050 the death ratio caused by bacterial infections can be higher than cancer. The aim of this study is to provide an alternative to currently available bone-infection treatments. Here we designed mesoporous hydroxyapatite nanocarriers functionalized with citrate (Ctr–mpHANCs). Amoxicillin (AMX) is used as a model drug to load in Ctr–mpHANCs, and the drug loading was more than 90% due to the porous nature of nanocarriers. Scanning electron microscopy shows the roughly spherical morphology of nanocarriers, and the DLS study showed the approximate size of 92 nm. The Brunauer–Emmett–Teller (BET) specific surface area and pore diameter was found to be about 182.35 m²/g and 4.2 nm, respectively. We noticed that almost 100% of the drug is released from the AMX loaded Ctr–mpHANCs (AMX@Ctr–mpHANCs) in a pH-dependent manner within 3 d and 5 d at pH 2.0 and 4.5, respectively. The sustained drug release behaviour was observed for 15 d at pH 7.4 and no RBCs hemolysis by AMX@Ctr–mpHANCs. The broth dilution and colony forming unit (CFU) assays were used to determine the antimicrobial potential of AMX@Ctr–mpHANCs. It was observed in both studies that AMX@Ctr–mpHANCs showed a significant reduction in the bacterial growth of S. aureus, E. coli, and P. aeruginosa as compared to Ctr–mpHANCs with no bacteria-killing. Thus, we proposed that Ctr–mpHANCs can be used as a drug carrier and a treatment option for bone infections caused by bacteria.

Development and characterization of a dry reservoir-hydrogel-forming microneedles composite for minimally invasive delivery of cefazolin

Cefazolin (CFZ) is one of the most extensively used cephalosporins. This antibiotic exerts its bactericidal activity by interfering with bacterial cell wall formation, leading to bacteriolysis. CFZ is highly polar, resulting in the drug having poor oral bioavailability. Accordingly, the antibiotic is administered via intramuscular or intravenous injections, which are both painful and invasive. Due to these limitations, there is an impetus to explore alternative drug delivery platforms which offer a minimally invasive approach to delivery CFZ into and across the skin. The current work presents the development of a composite pharmaceutical system composed of hydrogel-forming microneedles (MNs) in tandem with CFZ dry reservoirs. The hydrogel system was fabricated from Gantrez® S-97 and Carbopol® 974P NF crosslinked with PEG 10,000. Swelling kinetic studies showed that the hydrogel system developed was capable of achieving 4000% swelling in PBS pH 7.4. In addition, results from a solute diffusion study showed that CFZ was able to achieve ≈100% cumulative permeation across the swollen hydrogel film. When formulated into MNs, the hydrogel system was capable of breaching the stratum corneum, resulting in intradermal insertion of the hydrogel forming MNs into ex vivo neonatal porcine skin, as evidenced from optical coherence tomography. In addition, two different CFZ loaded dry reservoirs consisting of directly compressed tablets (DCT) and lyophilised (LYO) wafers were formulated and characterised. These dry reservoir systems showed fast dissolution, dissolving in phosphate buffer saline pH 7.4 in less than one minute. In vitro permeation studies, using full thickness ex vivo neonatal porcine skin were conducted. HPLC analysis demonstrated the dry reservoir combination consisting of DCT with hydrogel-forming MNs was capable of achieving up to 80 µg CFZ delivery into the epidermis within 2 hours of application. In addition, DCT reservoir coupled with hydrogel-forming MNs were able to deliver CFZ up to 1.8 mg into and across the skin at 24 hours. Should this system be translated into clinical practice, it may provide a minimally invasive strategy to administer CFZ for the treatment of infections such as septic arthritis, osteomyelitis and cellulitis.

Electrospun Nanofibers/Nanofibrous Scaffolds Loaded with Silver Nanoparticles as Effective Antibacterial Wound Dressing Materials

The treatment of wounds is expensive and challenging. Most of the available wound dressings are not effective and suffer from limitations such as poor antimicrobial activity, toxicity, inability to provide suitable moisture to the wound and poor mechanical performance. The use of inappropriate wound dressings can result in a delayed wound healing process. Nanosize range scaffolds have triggered great attention because of their attractive properties, which include their capability to deliver bioactive agents, high surface area, improved mechanical properties, mimic the extracellular matrix (ECM), and high porosity. Nanofibrous materials can be further encapsulated/loaded with metal-based nanoparticles to enhance their therapeutic outcomes in wound healing applications. The widely studied metal-based nanoparticles, silver nanoparticles exhibit good properties such as outstanding antibacterial activity, display antioxidant, and anti-inflammatory properties, support cell growth, making it an essential bioactive agent in wound dressings. This review article reports the biological (in vivo and in vitro) and mechanical outcomes of nanofibrous scaffolds loaded with silver nanoparticles on wound healing.

High-throughput fabrication of silk fibroin/hydroxypropyl methylcellulose (SF/HPMC) nanofibrous scaffolds for skin tissue engineering

Silk fibroin (SF) is a natural macromolecule material with good biocompatibility, which can be used to prepare a variety of biological materials. In this study, hydroxypropyl methylcellulose (HPMC) was applied to improve the properties of SF nanofibrous scaffolds (NFS) for skin tissue engineering applications. SF/HPMC NFS with varying weight ratios of SF: HPMC were prepared in batches by a modified free surface electrospinning. The effects of the varying weight ratio of SF: HPMC on the morphology, property and yield of SF/HPMC NFS were investigated. The results revealed that with the increase of HPMC contents, the hydrophilicity of SF/HPMC NFS would be improved, but the yield of that would decrease. Considering its effects on the morphology, property and yield of SF/HPMC NFS, the optimal weight ratio of SF: HPMC was 7:1. And SF/HPMC NFS with the weight ratio of 7:1 (SF/HPMC-7:1 NFS) had good mechanical property, hydrophilicity, porosity, swelling property and water vapor transmission rate (WVTR). In addition, the viability test results of human umbilical vein endothelial cells demonstrated that SF/HPMC-7:1 NFS maintained excellent biocompatibility for cell adhesion and proliferation.

Augmented healing of full thickness chronic excision wound by rosmarinic acid loaded chitosan encapsulated graphene nanopockets

Nanoparticles have emerged as an important carrier system to treat wounds as they permit the topical administration of an antimicrobial drug in a sustained and effective manner. On the other hand, if active excipients are added during the formulation, such as chitosan or graphene oxide, the developed Nano formulation could significantly improve its potential for chronic wound healing. Given that, we have conceived the fabrication and evaluation of rosmarinic acid loaded chitosan encapsulated graphene nanoparticles (RA-CH-G-NPOs) formulation to enhance wound healing capacity. The prepared nanoparticles were characterized by particle size, Zeta potential, FT-IR, SEM, TEM and AFM. It was observed the average diameter of RA-CH-G-NPOS is around 417.5 ± 18.3 nm and showed sustained release behavior. Optimized RA-CH-G-NPOs were incorporated into Carbopol gel and evaluated for drug content, pH, in vitro release, texture analysis, and viscosity. The antibacterial activity of optimized formulation was examined as a minimum inhibitory concentration against Staphylococcus aureus. The fabricated RA-CH-G-NPOs were than evaluated for in vitro antimicrobial activity by microdilution assay The combination of RA, Chitosan and Graphene oxide (GO) showed higher antibacterial activity of 0.0038 ± 0.2 mg/mL. Further, these nanoparticles were evaluated in- vivo for wound healing efficacy in Sprague Dawley rats. Histopathological evaluations demonstrated that RA-CH-G-NPOs showed significantly enhanced wound contraction, enhanced cell adhesion, epithelial migration, and high hydroxyproline content leading to faster and more efficient collagen synthesis as compared to plain carbopol, plain RA and controls. Hence the topical administration of fabricated RA-CH-G-NPOs appears to be an interesting and suitable strategy for the treatment of chronic wounds.

Development and characterization of rapid dissolving ornidazole loaded PVP electrospun fibers

Gingivitis is a common and mild form of periodontal disease and can be described as a limited inflammation of the gingiva. This study aims to develop and characterize rapid releasing mucoadhesive fibers containing ornidazole with electrospinning process for the treatment of gingivitis. Polyvinylpyrrolidone (PVP) was chosen as a polymer and used at different concentrations of 10%, 12.5%, and 15%. Scanning electron microscopy images showed that fiber diameters increased with increasing polymer concentrations. Tensile strength and elongation at break values of fibers increased with increasing PVP amount, whereas the loading of ornidazole into the fibers decreased these parameters. The contact angle values of all fibers were found to be 0° due to the hydrophilic nature of PVP. Ornidazole was released within 5 min and diffused from all of the fibers faster than that of gel and solution formulations. Electrospun ornidazole fibers were found efficient against Porphyromonas gingivalis in antimicrobial activity studies. The results demonstrated that ornidazole loaded fibers could be a potential drug delivery system for the treatment of gingivitis.

Development and Characterization of Novel Medicated Nanofiber for the Treatment of Periodontitis

Periodontitis is a common microbial infection that involves pocket formation due to the destruction of periodontal ligament. The present work is oriented to provide a holistic approach for the treatment of periodontitis comprising localized delivery of nanometric hydroxyapatite as a reinforcing filler and silver-metronidazole as periodontal pocket disinfectant adjunct to current periodontal therapy because of its broad-spectrum antimicrobial activity and low systemic toxicity. In the present work, electrospinning technique was used to prepare medicated nanofiber enriched with antibacterial-hydroxyapatite layers for dental application. The optimized formulation was characterized by SEM, FTIR, DSC, XRD, etc. Safety assessment and therapeutic potential of optimized formulation was evaluated in both in vitro and in vivo animal models. The newly synthesized complex (silver-metronidazole) exhibited higher antibacterial activity against the selected strain over the referenced silver and metronidazole. Results of in vitro studies suggested good compatibility of the metal complex with the polymer matrix. The drug release behavior from optimized formulation shows constant in vitro release behavior. Both in vitro and in vivo studies show broad-spectrum antimicrobial activity of the metal complex and demonstrate the potential of biomimetic nano-hydroxyapatite for filling periodontal defects. All these observations indicated that the above formulation could play a useful role in the treatment of periodontitis. Graphical Abstract ᅟ.

"Fusion and binding inhibition" key target for HIV-1 treatment and pre-exposure prophylaxis: targets, drug delivery and nanotechnology approaches

More than 35 million people are living with HIV worldwide with approximately 2.3 million new infections per year. Cascade of events (cell entry, virus replication, assembly and release of newly formed virions) is involved in the HIV-1 transmission process. Every single step offers a potential therapeutic strategy to halt this progression and HIV fusion into the human host cell is one such stage. Controlling the initial event of HIV-1 transmission is the best way to control its dissemination especially when prophylaxis is concerned. Action is required either on the HIV’s or host’s cell surface which is logically more rational when compared with other intracellular acting moieties. Aim of this manuscript is to detail the significance and current strategies to halt this initial step, thus blocking the entry of HIV-1 for further infection. Both HIV-1 and the possible host cell’s receptors/co-receptors are under focus while specifying the targets available for inhibiting this fusion. Current and under investigation moieties are categorized based on their versatile mechanisms. Advanced drug delivery and nanotechnology approaches present a key tool to exploit the therapeutic potential in a boosted way. Current drug delivery and the impact of nanotechnology in potentiating this strategy are detailed.

Nanochemistry of Protein-Based Delivery Agents

The past decade has seen an increased interest in the conversion of food proteins into functional biomaterials, including their use for loading and delivery of physiologically active compounds such as nutraceuticals and pharmaceuticals. Proteins possess a competitive advantage over other platforms for the development of nanodelivery systems since they are biocompatible, amphipathic, and widely available. Proteins also have unique molecular structures and diverse functional groups that can be selectively modified to alter encapsulation and release properties. A number of physical and chemical methods have been used for preparing protein nanoformulations, each based on different underlying protein chemistry. This review focuses on the chemistry of the reorganization and/or modification of proteins into functional nanostructures for delivery, from the perspective of their preparation, functionality, stability and physiological behavior.