Chitosan Polyethylene Glycol Research Articles

Enhanced adsorption of Congo red dye by CS/PEG/ZnO composite hydrogel: Synthesis, characterization, and performance evaluation

Hydrogels are 3D interconnected network polymer chains that are hydrophilic, swell in water and imbibe a significant amount of water. When hydrogel absorb water, dye molecules transfer to their surface, aiding adsorption. Adsorption is efficient, cheap, and versatile technique to remove dye from aqueous media. In this study, high-performance adsorbents from chitosan/polyethylene glycol (CS/PEG) hydrogel cross-linked with intermolecular H-bonds and chitosan/polyethylene glycol/ZnO (CS/PEG/ZnO) composite hydrogel cross-linked with Zn2+ were developed by an instantaneous gelation method. The prepared composite hydrogels were characterized by Fourier transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), transmission electron microscopy (TEM) and Zeta-sizer. The developed composite hydrogels effectively adsorbed Congo red (CR) dye from aqueous media. CR adsorption efficiency using adsorbent dosage, contact time, pH and temperature factors were conducted by batch adsorption experiments. The obtained results for CR adsorption equilibrium were compatible with the Langmuir model with maximum adsorption capacity (qmax) of 212.76 mg/g for CS/PEG and 256.41 mg/g for CS/PEG/ZnO composite hydrogel. The qmax was measured at pH 3 and 25 min and kinetic study confirmed that pseudo 2nd order kinetic model was best followed. Thermodynamic study indicated that the nature of the adsorption phenomena was physical, endothermic and spontaneous. The high adsorption efficiency is mainly ascribed to the protonation of –NH2 groups present in CS/PEG and CS/PEG/ZnO composite hydrogels which enhanced its electropositivity. Hydrogen bond formation and electrostatic attraction among adsorbent and dye govern the adsorption mechanism. It can be concluded that CS/PEG hydrogel and CS/PEG/ZnO composite hydrogels could be considered as efficient, beneficial and potential adsorbents for environmental remediation.

Synthesis of chitosan polyethylene glycol antibody complex for delivery of Imatinib in lung cancer cell lines.

Lung cancer is known as the most common cancer. Although the Ramucirumab antibody is a second-line treatment for lung cancer, the high interstitial fluid pressure limits the antibody's performance. In this way, Imatinib is a chemotherapeutic drug to reduce the interstitial fluid pressure. Up to now, unfortunately, both Ramucirumab and imatinib have not been reported in one nanosystem for cancer therapy. To fulfill this shortcoming, this paper aims to design a chitosan nanocarrier that loads imatinib and attaches to Ramucirumab for selective bonding to A549. Therefore, this paper aims to develop a polymeric nanosystem for non-small cell lung cancer (NSCLC) treatment. In first, the chitosan polyethylene glycol nanoparticle is synthesized, loaded with imatinib, and then targeted using Ramucirumab. Afterwards, the CS-PEG-Ab-Im by FTIR, TEM, DLS, zeta potential, and TGA techniques are characterized. The size of CS-PEG-Ab-Im was 25-30 nm, its surface charge was 13.1 mV, and the shape of CS-PEG-Ab-Im was nearly spherical and cylindrical. The therapeutic potential of CS-PEG-Ab-Im was assessed using the A549 cell line. According to the obtained results, the cell viability was 48% after 48 h of treatment of A549 cells using the IC50 concentration of CS-PEG-Ab-Im (100 nanomolar). Moreover, the apoptosis and cell cycle arrest percentages were increased by 3 and 6 times, respectively, as compared to free imatinib. Furthermore, the release rate of imatinib from CS-PEG-Ab-Im in an acidic medium was 17% during 1 h, indicating five times the imatinib release in the natural medium. Eventually, the result of flow cytometry indicates the more apoptotic effect of nanosystem to free imatinib and CS-PEG-Ab. Besides, cell arresting result exhibits the CS-PEG-Ab-Im and causes cell arrested at G1 by %8.17. Thus, it can be concluded that CS-PEG-Ab-Im can be an ideal nanosystem in NSCLC treatment.

Entrapment of Papain in Chitosan-Polyethylene Glycol Hybrid Nanohydrogels: Presenting a Model for Protein Delivery Systems.

In this study, the process of manufacturing nanohydrogels containing papain and how to release it was investigated. Chitosan nanohydrogels and chitosan-polyethylene glycol hybrid nanohydrogels were used to entrapment of papain as a protein model. In order to evaluate and confirm different properties of nanohydrogels such as size, shape, the rate of swelling and flexibility, different methods was used. The maximum amount of papain entrapment was observed in 0.75% concentration of chitosan and 1% concentration of sodium Tripolyphosphate (TPP) as linker. The results of scanning electron microscope (SEM) and X-ray diffraction (XRD) patterns showed that nanohydrogels containing papain on a nano scale are very porous and swollen. Differential scanning calorimetry (DSC) thermograms analysis showed that nanohydrogels have relatively good water absorption capacity. Also, by adding polyethylene glycol to chitosan, the melting temperature of hybrid nanohydrogels decreased and this can be a reason for the formation of flexible structures in these nanohydrogels. In chitosan nanohydrogels, the highest release rate of papain was observed at pH lower than 7 and high temperatures, but by adding polyethylene glycol to the chitosan, in addition to increasing papain release, a proper and continuous release of papain was observed at temperature and pH close to physiological conditions, especially at low ratios of polyethylene glycol. According to the present results, hybrid nanohydrogels can have a good potential in protein delivery systems in terms of structure and release.

Auranofin-Loaded Chitosan Nanoparticles Demonstrate Potency against Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) remains a clinical challenge due to molecular, metabolic, and genetic heterogeneity as well as the lack of validated drug targets. Thus, therapies or delivery paradigms are needed. Gold-derived compounds including the FDA-approved drug, auranofin have shown promise as effective anticancer agents against several tumors. To improve the solubility and bioavailability of auranofin, we hypothesized that the nanodelivery of auranofin using biodegradable chitosan modified polyethylene glycol (PEG) nanoparticles (NPs) will enhance anticancer activity against TNBC by comparing the best nanoformulation with the free drug. The selection of the nanoformulation was based on synthesis of various chitosan PEG copolymers via formaldehyde-mediated engraftment of PEG onto chitosan to form [chitosan-g-PEG] copolymer. Furthermore, altered physiochemical properties of the copolymer was based on the formaldehyde ratio towards nanoparticles (CP 1-4 NPs). Following the recruitment of PEG onto the chitosan polymer surface, we explored how this process influenced the stiffness of the nanoparticle using atomic force microscopy (AFM), a factor crucial for in vitro and in vivo studies. Our objective was to ensure the full functionality and inherent properties of chitosan as the parent polymer was maintained without allowing PEG to overshadow chitosan's unique cationic properties while improving solubility in neutral pH. Hence, CP 2 NP was chosen. To demonstrate the efficacy of CP 2 NP as a good delivery carrier for auranofin, we administered a dose of 3 mg/kg of auranofin, in contrast to free auranofin, which was given at 5 mg/kg. In vivo studies revealed the potency of encapsulated auranofin against TNBC cells with a severe necrotic effect following treatment superior to that of free auranofin. In conclusion, chitosan-g-PEG nanoparticles have the potential to be an excellent delivery system for auranofin, increasing its effectiveness and potentially reducing its clinical limitations.

Chitosan-Polyethylene Glycol Inspired Polyelectrolyte Complex Hydrogel Templates Favoring NEO-Tissue Formation for Cardiac Tissue Engineering.

Neo-tissue formation and host tissue regeneration determine the success of cardiac tissue engineering where functional hydrogel scaffolds act as cardiac (extracellular matrix) ECM mimic. Translationally, the hydrogel templates promoting neo-cardiac tissue formation are currently limited; however, they are highly demanding in cardiac tissue engineering. The current study focused on the development of a panel of four chitosan-based polyelectrolyte hydrogels as cardiac scaffolds facilitating neo-cardiac tissue formation to promote cardiac regeneration. Chitosan-PEG (CP), gelatin-chitosan-PEG (GCP), hyaluronic acid-chitosan-PEG (HACP), and combined CP (CoCP) polyelectrolyte hydrogels were engineered by solvent casting and assessed for physiochemical, thermal, electrical, biodegradable, mechanical, and biological properties. The CP, GCP, HACP, and CoCP hydrogels exhibited excellent porosity (4.24 ± 0.18, 13.089 ± 1.13, 12.53 ± 1.30 and 15.88 ± 1.10 for CP, GCP, HACP and CoCP, respectively), water profile, mechanical strength, and amphiphilicity suitable for cardiac tissue engineering. The hydrogels were hemocompatible as evident from the negligible hemolysis and RBC aggregation and increased adsorption of plasma albumin. The hydrogels were cytocompatible as evident from the increased viability by MTT (>94% for all the four hydrogels) assay and direct contact assay. Also, the hydrogels supported the adhesion, growth, spreading, and proliferation of H9c2 cells as unveiled by rhodamine staining. The hydrogels promoted neo-tissue formation that was proven using rat and swine myocardial tissue explant culture. Compared to GCP and CoCP, CP and HACP were superior owing to the cell viability, hemocompatibility, and conductance, resulting in the highest degree of cytoskeletal organization and neo-tissue formation. The physiochemical and biological performance of these hydrogels supported neo-cardiac tissue formation. Overall, the CP, GCP, HACP, and CoCP hydrogel systems promise novel translational opportunities in regenerative cardiology.

A novel chitosan-PEG hydrogel embedded with in situ silver nanoparticles of Clerodendrum glandulosum Lindl. extract: evaluation of its in vivo diabetic wound healing properties using an image-guided machine learning model.

The pathophysiology of chronic wounds related to diabetes mellitus is a result of a series of complications induced by hyperglycemia. The symptoms include impaired growth factor production, decreased keratinocyte proliferation and migration, reduced angiogenesis and cytokine synthesis, lowered matrix metalloproteinase (MMP) production, neuropathy, reduced nitric oxide synthase production, decreased fibroblast synthesis and migration, and impaired inflammatory cell functions. This multifaceted mechanism of diabetic wounds needs a suitable novel topical formulation that can deliver the active constituent by a controlled means, target the various stages of wound healing, absorb the wound exudates, and prevent secondary infections. To meet the above requirements, the Clerodendrum glandulosum (CG) extract reduced silver nanoparticle (AgNP) impregnated chitosan-polyethylene glycol (PEG) hydrogel was synthesized. The findings of the physicochemical characterization studies suggested that the hydrogel exhibited excellent formulation characteristics and showed controlled release for seven days, making it suitable for chronic wound healing studies. In subsequent studies, these formulations showed good antioxidant and antimicrobial properties, and hemocompatibility, with the least cytotoxic properties. The results of the diabetic wound healing studies showed a faster wound closure rate and improved extracellular matrix formation. These antioxidant, antimicrobial, anti-inflammatory and wound-healing properties suggest that the CG-AgNP loaded chitosan-PEG hydrogel is a promising material for novel topical formulation of diabetic wounds.

Bioavailability properties of intravaginal implants made from chitosan-PEG-PCL in simulated vaginal fluid and vagina of cattle

This study aimed to design and evaluate the bioavailability of intravaginal implants made from the biodegradable polymer chitosan-polyethylene glycol (PEG)-polycaprolactone (PCL) in simulated vaginal fluid (SVF) and the cow vagina. Implants were prepared using melt-ing and molding techniques with 26 different formulations. Next, the implants were immersed in 40 mL of SVF at a temperature of 37.8 ℃ and changes in implant morphology were observed every day until day 5. Implants that survived until day five were tested for further availability in the cow's vagina and observed daily for 2 weeks. The immersion test on SVF results showed that implants with a PEG content of 75-85% melt more quickly than implants with a PEG content of 20-72%. Implants containing 1-10% PCL eroded more rapidly in the SVF than those containing 22-80% PCL. Implants containing chitosan can remain stable in the SVF for longer than implants without chitosan. The bioavailability test in the cow's vagina showed that implants 21-23 persisted until the 10th day, while implants 24-26 were expelled from the cow's vagina during the test. Implant 21-23 is a promising formulation for the development of biodegradable intravaginal implants. By adjusting the composition of chitosan (between 14-18 wt%), PEG (maximum 72 wt%), and PCL (minimum 20 wt%), intravaginal implants were able to extend the bioavailability of both simulated vaginal fluid and the vagina of cattle.

Chitosan-PEG Gels Loaded with Jatropha mollissima (Pohl) Baill. Ethanolic Extract: An Efficient and Effective Biomaterial in Hemorrhage Control.

A lack of control over blood loss can have catastrophic implications, including death. Although several hemostatic medications have been employed to reduce bleeding, a vast majority of them are ineffective, expensive, or pose health risks to the patient. To overcome these constraints, chitosan-polyethylene glycol (CS-PEG) hemostatic gels loaded with ethanolic extract of Jatropha mollissima sap (EES) were prepared and their hemostatic, physicochemical, and cytotoxic properties were evaluated. The gels were produced by mixing CS with PEG (an external plasticizer) and EES. The phytochemical analysis revealed a significant concentration of total polyphenols and tannins content in the extract and catechin was identified as one of the key compounds of EES. Infrared spectroscopy analysis revealed the presence of EES in the gels, as well as the chemical interaction between CS and PEG. The gels were thermally stable between 25 and 37 °C (ambient and human body temperature range), had pseudoplastic deformation behavior (rheological properties preserved after shearing), were simple to inject (compression force 30 N), and were biocompatible. In vivo experiments showed that both CS-PEG-EES gels exhibited greater hemostatic action in preventing tail hemorrhage in Wistar rats, with decreased bleeding time and blood weight compared with unloaded CS-PEG gels (control groups) and Hemostank, a commercial product. However, the gel prepared with acetic acid was more efficient in controlling bleeding. These findings reveal that CS-PEG-EES gels can reduce hemorrhages and are a potent, simple, and safe hemostatic agent.

In Vitro, In Compost, and In Vivo Assessment of Chitosan-Polyethylene Glycol as an Intravaginal Insert for Progesterone Delivery in Sheep

In Vitro, In Compost, and In Vivo Assessment of Chitosan-Polyethylene Glycol as an Intravaginal Insert for Progesterone Delivery in Sheep

Application of mPEG-CS-cRGD/Bmi-1RNAi-PTX nanoparticles in suppression of laryngeal cancer by targeting cancer stem cells

Although surgery-based comprehensive therapy is becoming the main approach to treat laryngeal cancer, recurrence, metastasis, radiotherapy resistance and chemotherapy tolerance are still the main causes of death in patients. Targeted inhibition of laryngeal cancer stem cells has been considered as the consensus to cure laryngeal cancer. Our previous study has confirmed proto-oncogene Bmi-1 as a key regulator for self-renewal of laryngeal cancer stem cells. Targeted knockdown of Bmi-1 gene effectively inhibited the self-renewal and differentiation of laryngeal cancer stem cells, leading to the promoted sensitivity to chemotherapy including paclitaxel. However, due to off-target effects and quick degradation of the naked Bmi-1-RNAi small RNA oligo by nuclease in body fluids, it is urgently needed to develop a tumor-targeted delivery system with a protective shell. In this study, we designed and synthesized cRGD peptide-modified chitosan-polyethylene glycol slow-release nanoparticles (mPEG-CS-cRGD/Bmi-1RNAi-PTX) containing Bmi-1RNAi siRNA oligo and paclitaxel, which showed spherical in shape, 200 nm diameter in size, low cytotoxicity, strong DNA wrapping, resistance to nuclease degradation and high transfection efficiency to cells. Functional analysis indicated significant suppression of cell proliferation and migration and induction of apoptosis by the nanocomplex in laryngeal cancer cells in vitro. By application to the mouse model with laryngeal cancer, the nanocomplex inhibited tumor growth significantly in vivo. In addition, cRGD peptide, paclitaxel and Bmi-1 siRNA in the nanoparticles showed synergistic effects to suppress laryngeal cancer stem cells. In conclusion, this study not only developed a laryngeal tumor-targeted chemotherapeutic system, but also demonstrated a Bmi-1 RNAi-based chemotherapeutic strategy to inhibit cancer stem cells, having strong potential to treat laryngeal cancer patients suffering therapy resistance and/or tumor recurrence.

Preparation, characterization, and evaluation of antibacterial and cytotoxic activity of chitosan-polyethylene glycol nanoparticles loaded with amoxicillin as a novel drug delivery system

In this study, nanoparticles of amoxicillin (AMX) were prepared using chitosan (CHI) and polyethylene glycol (PEG). The physicochemical properties of the particles were investigated by FT-IR, DSC, SEM, and zeta potential analyses. The nanoparticles showed a spherical shape, and the average size of formulations was within the range of 696.20 ± 24.86 − 359.53 ± 7.41 nm. Zeta potential data demonstrated that the formulations had positive surface charges with a zeta potential range of 21.38 ± 2.28 − 7.73 ± 1.66 mV. FTIR analysis showed that the drug was successfully entrapped in the nanoparticles. DSC results suggested that the drug was present in amorphous form in the polymer matrix. In vitro release studies demonstrated that the release pattern consisted of two phases, with an initial burst release followed by a controlled and sustained release. The MTT assay results on mouse fibroblast cell line indicated that the prepared formulations did not affect the viability of the cells. In the in vitro antibacterial activity test, it was found that the drug-loaded nanoparticles have AMX-equivalent antibacterial activity against E. coli, and S. aureus. These findings revealed that the obtained nanoparticles might be a promising and safe nanocarrier system for efficient delivery of AMX.

Polyethylene glycol derivant crosslink and modify chitosan for tympanic membrane repair

This work focuses on developing a novel bioscaffold for tympanic membrane (TM) repair. A strategy to fabricate porous scaffolds is proposed, which is based on the chitosan membranes that were cross-linked and modified by tert-butyl acetoacetate esterified polyethylene glycol, while their mechanical properties and hydrophilicity were also improved. With two different crosslink methods, direct and freeze cross-linking, the chitosan-polyethylene glycol membranes were fabricated. Based on the morphology, hydrophilicity, and mechanical property, the biomedical scaffold has good enough properties for TM repair and the freeze cross-linking membrane is better. Our work provides a simple and reliable method for the preparation of bioscaffolds.

Preparation of a biomimetic bi-layer chitosan wound dressing composed of A-PRF/sponge layer and L-arginine/nanofiber

To better mimic the structure of skin tissue, the use of a multi-layered wound dressing has been proposed. In the present study, a sponge-nanofibrous bi-layer dressing is designed. For this purpose, a chitosan/polyethylene glycol (CsPEG) sponge with advanced platelet-rich fibrin (A-PRF) was prepared as the upper layer of wound dressing, and a Cs/L–arginine electrospun nanofiber layer as the bottom layer. After physical, chemical and mechanical evaluations, the release of platelet-derived growth factor-AB (PDGF-AB), vascular endothelial growth factor (VEGF) and L-arginine were investigated. The antibacterial activity, cell viability and attachment of Bi-layer1.5 dressing (CsPEG/1.5A-PRF sponge coated with Cs/0.5 L-arginine nanofibers) were significantly higher than other dressings. Also, Bi-layer1.5 dressing increased the angiogenic potential and accelerated the wound healing, compared to other samples. Given the promising obtained results, the use of Bi-layer1.5 wound dressing with the ability to release growth factors and L-arginine is highly recommended to treat full-thickness wounds.

Improvement of Biocatalytic Properties and Cytotoxic Activity of L-Asparaginase from Rhodospirillum rubrum by Conjugation with Chitosan-Based Cationic Polyelectrolytes.

L-asparaginases (L-ASNases, EC 3.5.1.1) are a family of enzymes that are widely used for the treatment of lymphoblastic leukemias. L-ASNase from Rhodospirillum rubrum (RrA) has a low molecular weight, low glutaminase activity, and low immunogenicity, making it a promising enzyme for antitumor drug development. In our work, the complex formation and covalent conjugation of the enzyme with synthetic or natural polycationic polymers was studied. Among non-covalent polyelectrolyte complexes (PEC), polyethyleneimine (PEI) yielded the highest effect on RrA, increasing its activity by 30%. The RrA-PEI complex had increased stability to trypsinolysis, with an inactivation constant decrease up to 10-fold compared to that of the native enzyme. The covalent conjugation of RrA with chitosan-PEI, chitosan-polyethylene glycol (chitosan-PEG), and chitosan-glycol resulted in an increase in the specific activity of L-asparagine (up to 30%). RrA-chitosan-PEG demonstrated dramatically (by 60%) increased cytotoxic activity for human chronic myeloma leukemia K562 cells in comparison to the native enzyme. The antiproliferative activity of RrA and its conjugates was significantly higher (up to 50%) than for that of the commercially available EcA at the same concentration. The results of this study demonstrated that RrA conjugates with polycations can become a promising strategy for antitumor drug development.

In silico modeling of emodin’s interactions with serine/threonine kinases and chitosan derivatives

Natural products are quickly gaining relevance as effective anticancer agents, and one example, emodin, possesses inhibitory activity against a broad spectrum of kinases, regulatory enzymes that control biological activity via phosphorylation of other molecules. Herein, through protein-ligand docking, we investigated the effect of the interaction of emodin with serine/threonine kinases, a subclass of kinases that is overexpressed in many cancers, which is implicated in phosphorylation cascades. These cascades act as intracellular messaging systems, and in the case of cancer, modify protein expression in the cell to essentially make it immortal. Thus, competitive inhibition by emodin can reduce the expression of a wide range of proteins required for essential cell function, resulting in cell death. Because the majority of serine/threonine kinases have similar active sites, we have successfully created a blueprint for emodin binding and interactions with active site residues, which include many hydrophobic interactions and minimal amounts of hydrogen bonding. Through molecular dynamics we found that emodin forms favorable interactions with chitosan and chitosan PEG (polyethylene glycol) copolymers, which could aid in loading drugs into nanoparticles (NPs) for targeted delivery to cancerous tissue. Both polymers demonstrated reasonable entrapment efficiencies, which encourages experimental exploration of emodin through targeted drug delivery vehicles and their anticancer activity.

Curcumin delivery using novel chitosan-polyethylene glycol diacrylate microencapsulation prepared via radiation-induced crosslinking

Curcumin delivery using novel chitosan-polyethylene glycol diacrylate microencapsulation prepared via radiation-induced crosslinking

Fabrication and Characterization of Chitosan-Polyethylene Glycol (Ch-Peg) Based Hydrogels and Evaluation of Their Potency in Rat Skin Wound Model.

Thermal burns are a major cause of death and suffering around the globe. They can cause debilitating, life-altering injuries as well as lead to significant psychological and financial consequences. Several research works have been conducted in attempt to find a wound healing therapy that is successful. At present, hydrogels have been widely used in cutting-edge research for this purpose because they have suitable properties. This study aimed to see how therapy with chitosan-polyethylene glycol (Ch-Peg) based hydrogels affected the healing of burn wounds in rats. With the concern of public health, xanthan gum (X), boric acid (B), gelatin (Ge), polyethylene glycol (Peg), chitosan (Ch), glutaraldehyde (G), and HPLC-grade water were prepared using X : Ge : G, X : Ge : Peg : G, X : Ge : Ch : G, X : Ge : Peg : Ch : G, X : Ge : B : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch : G. The produced composite hydrogels were examined for swelling ability, biodegradability, rheological characteristics, and porosity. The 3D structure of the hydrogel was revealed by scanning electron microscopy (SEM). After that, the structural characterization technique named Fourier-transform infrared spectroscopy (FTIR) was used to describe the composites (SEM). Lastly, in a rat skin wound model, the efficacy of the produced hydrogels was studied. Swelling ability, biodegradability, rheological properties, and porosity were all demonstrated in composite hydrogels that contained over 90% water. Hydrogels with good polymeric networks and porosity were observed using SEM. The existence of bound water and free, intra- and intermolecule hydrogen-linked OH and NH in the hydrogels was confirmed using FTIR. In a secondary burned rat model, all hydrogels showed significant wound healing effectiveness when compared to controls. When compared to other composite hydrogels, wounds treated with X : Ge : Peg : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch:G recovered faster after 28 days. In conclusion, this research suggests that X : Ge : Peg : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch : G could be used to treat skin injuries in the clinic.

Adsorption of Silicate Anions from Geothermal Brine Using Chitosan-Polyethylene Glycol Composite to Prevent Silica Scaling on the Dieng Geo Dipa Geothermal Energy System

Silica scaling is a common problem in geothermal power generation facilities which inhibits electricity generation. In order to provide a solution to this problem, the removal of silicate ions using CPEG-TOMAC (Chitosan-polyethylene glycol–trioctyl methyl ammonium chloride) membrane adsorbent was investigated for geothermal brine from Geo Dipa Energy, Dieng. The process is dependent on contact time, pH, and the concentration of silicate. An adsorption batch study that used adsorbents for the geothermal brine of the Dieng Geo Dipa reactor 28A showed that CPEG TOMAC at pH 6 resulted in an adsorption capacity of 72.6 mg g–1. Furthermore, the adsorption of silicate ions onto the membrane followed pseudo-second-order kinetics and the Freundlich isotherm model.

Preparation, characterization, and in vitro release study of vincristine sulfate-loaded chitosan–polyethylene glycol–oleic acid composites

Vincristine sulfate (VCS) was used in combination with other chemotherapeutic agents for the treatment of a variety of cancers, including acute lymphoblastic leukemia, cervical cancer, and breast cancer. However, rapid release of the drug at the site of specific action was still a challenge for antitumor treatment. Recently, hybrid carriers bearing the versatile properties of each component were promising materials in order to improve the effects of therapeutic drugs. This work aimed to prepare and characterize chitosan (CHS)–polyethylene glycol (PEG)–oleic acid (OA) composites as a carrier for VCS delivery. The structure, thermal stability, and surface morphology of CHS/PEG/OA composites were characterized by using Fourier transform infrared spectroscopy, thermal gravimetric analysis, differential thermal analysis, differential scanning calorimeter, scanning electron microscopy, and atomic force microscopy. Additionally, swelling degree, water uptake capacity, gas permeability, water contact angle, and in vitro hydrolytic degradation properties of the composites were examined in detail. The VCS-loaded CHS/PEG/OA composites were prepared and drug-loading efficiency was evaluated. CPO-2 sample with a loading efficiency of 64.1 ± 0.6% was selected for in vitro release. due to the highest drug loading efficiency. In vitro release behavior was performed in phosphate-buffered saline buffer (pH 7.4). The release of VCS was completed in almost 24 h and the release data were best fitted to Korsmeyer–Peppas model. The release results revealed that CHS/PEG/OA composites with slow-release behavior could be a promising drug carrier for therapeutic drugs such as VCS.

Development of oral aprepitant-loaded chitosan–polyethylene glycol-coated cyclodextrin nanocapsules: formulation, characterization, and pharmacokinetic evaluation

Aprepitant (APRT), a selective neurokinin 1 antagonist, is clinically used in the prevention of acute and delayed chemotherapy-induced nausea and vomiting. The low solubility of APRT, which limits its oral bioavailability, is overcome by nanonization. This study aimed to design and evaluate novel in vitro and in vivo chitosan (CS)–polyethylene glycol (PEG)-coated cyclodextrin (CD) nanoparticles and nanocapsules to enhance the solubility and oral bioavailability of APRT. A novel amphiphilic CD derivative with alkyl chains of 9 carbons (ACD-C9) was synthesized to form nanoparticles and nanocapsules by using nanoprecipitation. The nanocarriers were coated with the CS–PEG conjugate to increase their biological interaction with cell membranes via the positive charge and penetration-enhancer properties of CS. The nanosystems were evaluated for particle size, surface charge, drug loading, imaging, release, cell culture, and oral bioavailability in an animal model. The CS–PEG-coated nanosystems had particle size of 400–550 nm, a narrow polydispersity index, positive zeta potential, and favorable drug loading (55 and 93% for nanoparticles and nanocapsules, respectively). Sustained release was observed within 24 h. Blank nanoparticles and nanocapsules were non-cytotoxic against the L929 cell line. The intestinal permeability of the nanocarriers was 2–threefold (2-3 fold) higher than that of the drug solution, and the nanocapsules afforded the highest APRT permeability through Caco-2 cells. Oral bioavailability studies in rats revealed comparable degree of drug absorption between nanocapsules and commercial APRT products. Oral ACD-C9 nanocapsules have the potential for the treatment of chemotherapy-induced nausea and vomiting.