Development and characterization of chitosan nanoparticles loaded nanofiber hybrid system for vaginal controlled release of benzydamine

Vaginal infections caused by various pathogens such as fungi, viruses and protozoa are frequently seen. Systemic and local treatments can be applied to eliminate these infections. Novel vaginal drug delivery systems can be used to provide local treatment. Vaginal drug delivery systems prevent systemic side effects and can provide long-term drug release in the vaginal area. Nanofibers and nanoparticles have a wide range of applications and can also be preferred as vaginal drug delivery systems. Benzydamine is a non-steroidal anti-inflammatory and antiseptic drug which is used for treatment of vaginal infections. The aim of this study was to compare the nanofiber and gel formulations containing lyophilized benzydamine nanoparticles with nanofiber and gel formulations containing free benzydamine, and to provide prolonged release for protection from the vaginal infections. Ionic gelation method was used for the preparation of benzydamine loaded nanoparticles. To produce benzydamine nanoparticles loaded nanofiber formulations, polyvinylpyrrolidone (PVP) solutions were prepared at 10% concentrations and mixed with nanoparticles. Hydroxypropyl methylcellulose (HPMC) was used as a gelling agent at the concentration of 1% for the vaginal gel formulation. Nanoparticles were characterized in terms of zeta potential, polydispersity index and particle size. Viscosity, surface tension and conductivity values of the polymer solutions were measured for the electrospinning. Mechanical properties, contact angle and drug loading capacity of the fibers were determined. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), fourier-transform infrared (FT-IR) spectroscopy, mucoadhesion, ex vivo permeability studies and in vitro release studies were performed for the selected formulations. Ex vivo permeability studies were performed using Franz diffusion cell method. SEM and TEM images showed that fiber diameters increased with loading of nanoparticles. DSC studies showed no interaction between excipients used in the formulation. Tensile strength and elongation at break values of the fibers increased with the loading of nanoparticles, and the contact angle values of the fibers were found to be 0°. Addition of benzydamine nanoparticles to gel and nanofiber formulations increased mucoadhesion compared to free benzydamine loading formulations. Benzydamine nanoparticle loaded gel and nanofiber formulations penetrated slower than that of free benzydamine gel and fiber formulations. The results demonstrated that benzydamine and benzydamine nanoparticle loaded fibers and gels could be a potential drug delivery system for the treatment of vaginal infections. Chitosan nanoparticle loaded nanofiber formulations are offered as an alternative controlled release vaginal formulations for vaginal infections.

Innovative Skin Product Emulsions with Enhanced Antioxidant, Antimicrobial and UV Protection Properties Containing Nanoparticles of Pure and Modified Chitosan with Encapsulated Fresh Pomegranate Juice

In the present study, a chitosan (CS) derivative with the 2-(Methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SDAEM) zwitterionic monomer was prepared through chemical modification. The successful synthesis of CS-SDAEM was confirmed by Fourier-transform Infrared (FTIR) and Nuclear Magnetic Resonance (¹H-NMR) spectroscopies. Its crystallinity was studied by X-ray Diffraction (XRD), while in vitro cytotoxicity and cell viability assays established its biocompatibility. Filtered fresh pomegranate juice (PJ) was loaded in nanoparticles of neat CS and its derivative via ionic gelation method. Dynamic Light Scattering (DLS) revealed nanoparticles sizes varying between 426 nm and 4.5 μm, indicating a size-dependence on the polymer concentration used during encapsulation. High-performance liquid chromatography coupled with photodiode array and electrospray ionization mass spectrometry detection (LC-PDA-ESI/MS) revealed that PJ active compounds were successfully and in sufficient amounts encapsulated in the nanoparticles interior, whereas XRD indicated a crystalline structure alteration after nanoencapsulation. The resulted PJ-loaded nanoparticles were further utilized for the preparation of innovative O/W cosmetic emulsions. All produced emulsions exhibited good pH and viscosity stability for up to 90 days, while the sun protection factor (SPF) was enhanced due to the presence of the PJ. Enhanced antioxidant and antimicrobial properties due to the phenolic compounds of PJ were also observed.

Chitosan and its Derivatives for Ocular Delivery Formulations: Recent Advances and Developments

Chitosan (CS) is a hemi-synthetic cationic linear polysaccharide produced by the deacetylation of chitin. CS is non-toxic, highly biocompatible, and biodegradable, and it has a low immunogenicity. Additionally, CS has inherent antibacterial properties and a mucoadhesive character and can disrupt epithelial tight junctions, thus acting as a permeability enhancer. As such, CS and its derivatives are well-suited for the challenging field of ocular drug delivery. In the present review article, we will discuss the properties of CS that contribute to its successful application in ocular delivery before reviewing the latest advances in the use of CS for the development of novel ophthalmic delivery systems. Colloidal nanocarriers (nanoparticles, micelles, liposomes) will be presented, followed by CS gels and lenses and ocular inserts. Finally, instances of CS coatings, aiming at conferring mucoadhesiveness to other matrixes, will be presented.

Chitosan Derivatives with Mucoadhesive and Antimicrobial Properties for Simultaneous Nanoencapsulation and Extended Ocular Release Formulations of Dexamethasone and Chloramphenicol Drugs

The aim of this work was to evaluate the effectiveness of neat chitosan (CS) and its derivatives with 2-acrylamido-2-methyl-1-propanesulfonic acid (AAMPS) and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (MEDSP) as appropriate nanocarriers for the simultaneous ocular administration of dexamethasone sodium phosphate (DxP) and chloramphenicol (CHL). The derivatives CS-AAMPS and CS-MEDSP have been synthesized by free-radical polymerization and their structure has been proved by Fourier-Transformed Infrared Spectroscopy (FT-IR) spectroscopy. Both derivatives exhibited low cytotoxicity, enhanced mucoadhesive properties and antimicrobial activity against Staphylococcus aureus (S.aureus) and Escherichia coli (E. coli). Encapsulation was performed via ionic crosslinking gelation using sodium tripolyphosphate (TPP) as the crosslinking agent. Dynamic light scattering measurements (DLS) showed that the prepared nanoparticles had bimodal distribution and sizes ranging from 50–200 nm and 300–800 nm. Drugs were encapsulated in their crystalline (CHL) or amorphous (DexSP) form inside nanoparticles and their release rate was dependent on the used polymer. The CHL dissolution rate was substantially enhanced compared to the neat drug and the release time was extended up to 7 days. The release rate of DexSP was much faster than that of CHL and was prolonged up to 3 days. Drug release modeling unveiled that diffusion is the main release mechanism for both drugs. Both prepared derivatives and their drug-loaded nanoparticles could be used for extended and simultaneous ocular release formulations of DexSP and CHL drugs.

Marine-Derived Polymeric Materials and Biomimetics: An Overview

The review covers recent literature on the ocean as both a source of biotechnological tools and as a source of bio-inspired materials. The emphasis is on marine biomacromolecules namely hyaluronic acid, chitin and chitosan, peptides, collagen, enzymes, polysaccharides from algae, and secondary metabolites like mycosporines. Their specific biological, physicochemical and structural properties together with relevant applications in biocomposite materials have been included. Additionally, it refers to the marine organisms as source of inspiration for the design and development of sustainable and functional (bio)materials. Marine biological functions that mimic reef fish mucus, marine adhesives and structural colouration are explained.

Chitosan Nanoparticles with Encapsulated Natural and UF-Purified Annatto and Saffron for the Preparation of UV Protective Cosmetic Emulsions

The aim of the present work is to evaluate the preparation of sunscreen emulsions based on chitosan (CS) nanoparticles with annatto, ultrafiltrated (UF) annatto, saffron, and ultrafiltrated saffron. Ionic gelation was used for the preparation of chitosan nanoparticles, while their morphological characteristics and physicochemical properties were evaluated via Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and dynamic light scattering (DLS). Results showed that the prepared nanoparticles ranged from ~150 to ~500 nm and had a spherical or irregular shape. In the case of annatto and UF annatto, due to the formation of H-bonds, the sunscreen agents were amorphously dispersed within CS nanoparticles, while in the case of saffron and UF saffron, crystalline dispersion was observed. All encapsulated materials had good thermal stability as well as color stability. In a further step, sunscreen emulsions were prepared based on the formed CS-sunscreen nanoparticles and evaluated for their stability in terms of pH and viscosity, along with their ultraviolet (UV) radiation protection ability in terms of sun protection factor (SPF). All prepared emulsions showed low cytotoxicity and good storage stability for up to 90 days, while minimum sunscreen protection was observed with SPF values varying from 2.15 to 4.85.

Supramolecular Confinement within Chitosan Nanocomposites Enhances Singlet Oxygen Generation

The synthesis of water-soluble chitosan nanocomposites incorporating BODIPY and the investigation of their photosensitization properties is reported. It was observed that the singlet oxygen generation capability of nanocomposites containing a mixture of BODIPY and iodine-containing molecules are higher than that of the nanocomposites containing BODIPY alone. It is hypothesized that the supramolecular interactions between BODIPY and iodine-containing molecules confined within the nanocomposites lead to the enhanced singlet oxygen generation.

Thiolated Chitosan Masked Polymeric Microspheres with Incorporated Mesocellular Silica Foam (MCF) for Intranasal Delivery of Paliperidone

In this study, mesocellular silica foam (MCF) was used to encapsulate paliperidone, an antipsychotic drug used in patients suffering from bipolar disorder. MCF with the drug adsorbed was further encapsulated into poly(lactic acid) (PLA) and poly(lactide-co-glycolide) (PLGA) 75/25 w/w microspheres and these have been coated with thiolated chitosan. As found by TEM analysis, thiolated chitosan formed a thin layer on the polymeric microspheres' surface and was used in order to enhance their mucoadhesiveness. These microspheres aimed at the intranasal delivery of paliperidone. The DSC and XRD studies showed that paliperidone was encapsulated in amorphous form inside the MCF silica and for this reason its dissolution profile was enhanced compared to the neat drug. In coated microspheres, thiolated chitosan reduced the initial burst effect of the paliperidone dissolution profile and in all cases sustained release formulations have been prepared. The release mechanism was also theoretically studied and three kinetic models were proposed and successfully fitted for a dissolution profile of prepared formulations to be found.

Delivery of siRNA targeting HIF-1α loaded chitosan modifiedd-α-tocopheryl polyethylene glycol 1000 succinate-b-poly(ε-caprolactone-ran-glycolide) nanoparticles into nasopharyngeal carcinoma cell to improve the therapeutic efficacy of cisplatin

Nanoformulation of siRNA targeting HIF-1α loaded chitosan modified TPGS-b-(PCL-ran-PGA) NPs could increase the therapeutic potential of cisplatin for nasopharyngeal carcinoma.

Preparation of GST Inhibitor Nanoparticle Drug Delivery System and Its Reversal Effect on the Multidrug Resistance in Oral Carcinoma

During the chemotherapy of cancer, drug resistance is the first issue that chemotherapeutic drugs cannot be effectively used for the treatment of cancers repeatedly for a long term, and the main reason for this is that tumor cell detoxification is mediated by GSH (glutathione) catalyzed by GST (glutathione-S-transferase). In this study, a GST inhibitor, ethacrynic acid (ECA), was designed to be coupled with methoxy poly(ethylene glycol)-poly(lactide) (MPEG-PLA) by disulfide bonds to prepare methoxy poly(ethylene glycol)-poly(lactide)-disulphide bond-mthacrynic acid (MPEG-PLA-SS-ECA) as a carrier material of the nanoparticles. Nanoparticles of pingyangmycin (PYM) and carboplatin (CBP) were prepared, respectively, and their physicochemical properties were investigated. The ECA at the disulfide could be released in the presence of GSH, the pingyangmycin, carboplatin and ECA were all uniformly released, and the nanoparticles could release all the drugs completely within 10 days. The half maximal inhibitory concentration (IC₅₀₎ of the prepared MPEG-PLA-SS-ECA/CBP and MPEG-PLA-SS-ECA/PYM nanoparticles in drug-resistant oral squamous cell carcinoma cell lines SCC15/CBP and SCC15/PYM cells was 12.68 μg·mL^-¹ and 12.76 μg·mL^-¹, respectively; the resistant factor RF of them in the drug-resistant cells were 1.51 and 1.24, respectively, indicating that MPEG-PLA-SS-ECA nanoparticles can reverse the drug resistance of these two drug-resistant cells.