Solvent Evaporation Technique Research Articles

Developed meloxicam loaded microparticles for colon targeted delivery: Statistical optimization, physicochemical characterization, and in-vivo toxicity study.

The study aimed to fabricate and evaluate Meloxicam (MLX) loaded Hydroxypropyl Methylcellulose (HPMC) microparticles for colon targeting because MLX is a potent analgesic used in the treatment of pain and inflammation associated with colorectal cancer (CRC). Nevertheless, its efficiency is limited by poor solubility and gastrointestinal tracts (GIT) associated side effects. Seventeen formulations of MLX loaded HPMC microparticles were fabricated by the oil-in-oil (O/O)/ emulsion solvent evaporation (ESE) technique. A 3-factor, 3-level Box Behnken (BBD) statistical design was used to estimate the combined effects of the independent variables on the dependent variables (responses), such as the percent yield (R1), the entrapment efficiency (EE) (R2), mean particle size (R3) and in vitro percentage of cumulative drug release (R4). For physicochemical characterization FTIR, XRD, DSC, and SEM analyses were performed. Biocompatibility and non-toxicity were confirmed by in-vivo acute oral toxicity determination. The percentage yield and EE were 65.75-90.71%, and 70.62-88.37%, respectively. However, the mean particle size was 62.89-284.55 μm, and the in vitro cumulative drug release percentage was 74.25-92.64% for 24 hours. FTIR analysis showed that the composition of the particles was completely compatible, while XRD analysis confirmed the crystalline nature of the pure drug and its transition into an amorphous state after formulation. DSC analysis revealed the thermal stability of the formulations. The SEM analysis showed dense spherical particles. The toxicity study in albino rabbits showed no toxicity and was found biocompatible. The histopathological evaluation showed no signs of altered patterns. Results of this study highlighted a standard colonic drug delivery system with the ability to improve patient adherence and reduce GIT drug-associated side effects in CRC treatment.

Ex-Vivo Evaluation of Eflornithine Hydrochloride Loaded Solid Lipid Microparticles Based Cream

Hirsutism is an unpleasant condition that affects a large number of women. Hirsutism can make females feel exceedingly self-conscious, jeopardizing their sense of femininity as well as their self-esteem. They are employing established treatments without evaluating their negative consequences, necessitating the development of new procedures. EFH loaded solid lipid microparticles (EFH-SLM) were manufactured using the solvent evaporation technique using polymers. Hair regrowth investigations in healthy Swiss albino female mice were carried out ex-vivo. Animals treated with EFH-Cream and EFH-SLM-Cream had the fairest and least dense hair densities on day 21. In comparison to regular EFH-Cream, this revealed that cream loaded with EFH-SLM was more efficient. On day 21, hair weight per cm2 was weighed for all groups of animals, and it was discovered that there was a substantial difference between animals treated with EFH-cream and EFH-SLM-Cream, which could be related to EFH-increased SLM's permeability. In comparison to animals treated with EFH-Cream and marketed EFH cream, animals treated with EFH-SLM-cream had fewer or no skin rashes or inflammation.

Encapsulation of Coconut Oil Using Ethyl Cellulose as Coating Shell for Thermoregulating Response of Cotton

ABSTRACT Phase change material (PCM) with its heat storing and releasing ability provides a thermoregulating effect. For thermoregulation, different kinds of PCMs are used among which the paraffins are widely used due to their high enthalpy values. Here, coconut oil was used as PCM in the core by encapsulating cellulose-based shell. Mostly, melamine formaldehyde-based shells are used for encapsulation due to their ease in formation and have toxic effect on humans and environment, so bio-degradable solution is provided using cellulose based shell with coconut oil as core PCM. Ethyl cellulose with its outstanding properties and biocompatible nature provides eco-friendly nanoencapsulation. This research work reports the development of nanocapsules of ethyl cellulose as shell and coconut oil as core PCM via solvent evaporation technique and its application on cotton fabric through coating. The encapsulation was performed using general full factorial design of experiment containing three factors and three levels of each factor except the first factor (type of solvent). The resultant capsules and fabric were characterized using Zeta Sizer, Differential Scanning Calorimeter, Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, and Infrared thermography. Different combination of factors used in experimentation resulted in the investigation of effect of solvents, emulsifiers, etc. on particle size.

Effect of the Emulsion Solvent Evaporation Technique Cosolvent Choice on the Loading Efficiency and Release Profile of Anti-CD47 from PLGA Nanospheres

IntroductionSide effects associated with using antibodies as therapeutics can limit systemic administration at the high concentrations often needed for therapeutic impact. Thus, therapeutic antibodies are usually considered for targeted delivery. Antibody encapsulation in polymeric nanoparticles via the emulsion-based nanofabrication methods typically yields low loading efficiencies. Therefore, the fabrication techniques need to be modified to maximize the loading efficiency of antibodies. In this work, we utilized various cosolvents with the emulsion solvent evaporation technique to improve the loading efficiency of anti-CD47, a therapeutic antibody used to block CD47 activity in atherosclerotic plaques and cancer lesions. Methods and ResultsThe double emulsion solvent evaporation technique was used to fabricate anti-CD47-loaded polymeric nanoparticles. The primary oil phase solvent, chloroform, was doped with different cosolvents, including ethyl acetate, acetonitrile, ethanol, and methanol, to investigate the impact of cosolvents on the loading efficiency of anti-CD47. The release profile and loading efficiency were quantified by measuring the fluorescence signal of the released antibody. The activity of the antibody released from particles fabricated in the presence of the cosolvent was confirmed by quantifying its adherence to red blood cells. Ethyl acetate was the optimum cosolvent, improving the loading efficiency of anti-CD47 in poly(lactic-co-glycolic acid), PLGA, nanoparticles to 90% or higher, and the antibody was found to retain its activity after being released from nanoparticles. ConclusionOur results demonstrate that a minimum amount of a cosolvent with minimal hydrophilicity can stabilize the antibody in the oil phase; thus, improving the antibody's loading efficiency significantly.

Enchant O[sbnd]H⋅⋅⋅O interactions in hydrated 6-amino-2-methoxypyrimidin-4(3H)one resembles as water flow in the channel: Crystallographic and theoretical investigations

In this present investigation, a hydrated single crystal of new , 6-amino-2-methoxypyrimidin-4(3H)one (AMP) has been grown using slow solvent evaporation technique. The single crystal X-ray diffraction technique has been used to study the structure of pyrimidinone derivative, which discloses the role of two lattice waters molecules in the crystal packing called hydrated 6-amino-2-methoxypyrimidin-4(3H)one (HAMP). These kinds of hydrated forms incorporate noticeable improvements in the crucial physical properties of API molecules, like stability and bioavailability. The crystal structure of HAMP is greatly stabilized by the significant O—H⋯O, N—H⋯O, and N—H⋯N H-bonding (HB) interactions. With the help of DFT computational analysis, molecular geometry and global reactive parameters have been calculated to better understand the molecular properties of HAMP. The Hirshfeld surface (HS) and accompanying 2D fingerprint plots have been used to explore the nature of all of these non-classical HB interactions, as well as their relative roles in creating supramolecular structures. The energy difference between HOMO-LUMO is found to be 5.414 eV which indicates the possibility of a charge transfer in the HAMP molecule. The molecular electrostatic potential (MEP) has been plotted to understand the charge distribution, electrophilic and nucleophilic sites in the HAMP molecule. Moreover, the quantum theory of atoms in molecules (QTAIM) framework, non-covalent interactions (NCI), reduced density gradient (RDG), electron localization function (ELF), and electron density have been used to describe the nature of non-covalent interactions and electron clouds present in the HAMP crystal.

Effect of Solvents, Stabilizers and the Concentration of Stabilizers on the Physical Properties of Poly(d,l-lactide-co-glycolide) Nanoparticles: Encapsulation, In Vitro Release of Indomethacin and Cytotoxicity against HepG2-Cell

A biocompatible, biodegradable and FDA-approved polymer [Poly lactic-co-glycolic acid (PLGA)] was used to prepare the nanoparticles (NPs) to observe the effect of solvents, stabilizers and their concentrations on the physical properties of the PLGA-NPs, following the encapsulation and in vitro release of Indomethacin (IND). PLGA-NPs were prepared by the single-emulsion solvent evaporation technique using dichloromethane (DCM)/chloroform as the organic phase with Polyvinyl-alcohol (PVA)/Polyvinylpyrrolidone (PVP) as stabilizers to encapsulate IND. The effects of different proportions of PVA/PVP with DCM/chloroform on the physiochemical properties (particle size, the polydispersity index, the zeta potential by Malvern Zetasizer and morphology by SEM) of the NPs were investigated. DSC was used to check the physical state, the possible complexation of PLGA with stabilizer(s) and the crystallinity of the encapsulated drug. Stabilizers at all concentrations produced spherical, regular-shaped, smooth-surfaced discrete NPs. Average size of 273.2–563.9 nm was obtained when PVA (stabilizer) with DCM, whereas it ranged from 317.6 to 588.1 nm with chloroform. The particle size was 273.2–563.9 nm when PVP was the stabilizer with DCM, while it was 381.4–466.6 nm with chloroform. The zeta potentials of PVA-stabilized NPs were low and negative (−0.62 mV) while they were comparatively higher and positive for PVP-stabilized NPs (+17.73 mV). Finally, drug-loaded optimal NPs were composed of PLGA (40 mg) and IND (4 mg) in 1 mL DCM/chloroform with PVA/PVP (1–3%), which resulted in sufficient encapsulation (54.94–74.86%) and drug loading (4.99–6.81%). No endothermic peak of PVA/PVP appeared in the optimized formulation, which indicated the amorphous state of IND in the core of the PLGA-NPs. The in vitro release study indicated a sustained release of IND (32.83–52.16%) from the PLGA-NPs till 72 h and primarily followed the Higuchi matrix release kinetics followed by Korsmeyer–Peppas models. The cell proliferation assay clearly established that the organic solvents used to prepare PLGA-NPs had evaporated. The PLGA-NPs did not show any particular toxicity in the HepG2 cells within the dose range of IND (250–500 µg/mL) and at an equivalent concentration of PLGA-NPs (3571.4–7142.7 µg/mL). The cytotoxicity of the hepatotoxic drug (IND) was reduced by its encapsulation into PLGA-NPs. The outcomes of this investigation could be implemented to prepare PLGA-NPs of acceptable properties for the encapsulation of low/high molecular weight drugs. It would be useful for further in vitro and in vivo applications to use this delivery system.

Design of polymeric nanoparticles for oral delivery of capreomycin peptide using double emulsion technique: Impact of stress conditions

Peptides are short polymers of amino acids that are unstable at drastic conditions including highly acidic or highly alkaline media, high temperature and high shear forces. Polymeric nanoparticles as carrier for peptides are the most desirable formulation in pharmaceutical field than other colloidal systems because of their stability in biological environment. Two different biodegradable polymers were chosen to formulate nanoparticles as carriers for capreomycin sulfate (CMS) peptide. Chitosan was selected as a water soluble polymer, while, poly(lactic-co-glycolic) acid (PLGA) polymer is soluble in organic solvents. Double emulsion solvent evaporation technique was used in the formulation of the nanoparticles. This method required applying of thermal, mechanical and chemical stresses that could have impact on peptide degradation that should be considered in the design of nanoparticles. Many formulation factors for polymeric nanoparticles optimization were tested including: probe sonication intensity and time, homogenization speed, pH of dispersion media, drug:polymer ratios, type and concentration of crosslinking agents and concentration of the stabilizer. Controlling these factors with monitoring of peptide degradation allowed to optimize polymeric nanoparticles having the smallest possible particle sizes (343.7–1656.5 nm) with the highest entrapment efficiencies (17.30–62.30%). The produced polymeric nanoparticles were tested for in vitro drug release in phosphate buffer pH 6.8. Different CMS release profiles were observed (15.52–72.44%) where PLGA NPs showed significant slower release compared with that of chitosan NPs.

Synthesis, spectral characterization, single crystal X-ray diffraction, and antimicrobial properties of 1-(4-iodo-1-hydroxynaphthalen-2-yl)ethan-1-one

This paper describe synthesis of 1-(4-iodo-1-hydroxynaphthalen-2-yl)ethan-1-one (3) from 2-acetyl-1-naphthol 2 by using I 2 /HIO 3 in ethanol under reflux condition. The structure of titled compound confirmed through spectral techniques. A well grown single crystal was developed using solvent evaporation technique for their X-ray diffraction analysis. The results showed that compound 3 crystallize in the monoclinic crystal system with Z value of four and space group symmetry P21/n. Whereas unit cell dimensions and angles are a; 7.5183 Å, b; 9.7529 Å, c; 14.8633 Å, α; 90°, β; 91.923°, γ; 90°. Moreover crystal data and packing view demonstrated that crystal was stabilized by one strong classical hydrogen bond interaction (O(2)-H(2)...O(1)) and two weak intermolecular hydrogen bonding. The synthesized compound was evaluated for antimicrobial activity against the Bacillus subtilis, Escherichia Coli, Pseudomonas Aeruginosa, Aspergillus flavus, Aspergillus Niger and Candida albicans organisms. Biological activity revealed that the compound 3 show significant to moderate activity. Single crystal packing view of 1-(4-iodo-1-hydroxynaphthalen-2-yl)ethan-1-one.

A Healable Epoxy with Comprehensive Properties by Incorporating Thermoplastic Epoxy Microspheres

AbstractHealable materials by incorporating thermoplastic particles as healants can not only possess healability, but also retain the intrinsic properties of the host matrix. Herein, solid healant microspheres made of a thermoplastic epoxy poly(bisphenol A‐co‐epichlorohydrin) are fabricated using a solvent evaporation technique and then incorporated into the thermosetting epoxy to formulate a healable epoxy. Slight dissolution of the microspheres is observed during the curing process of the matrix, which strengthens the bond between the microspheres and matrix. The healing performance is tested after heating at 180 °C for 20 min, and maximum healing efficiency of about 95% is achieved. Due to the thermoplastic feature of the healant, this healable system possesses multi‐time healability. Expectedly, it shows the solid microspheres increase the fracture toughness and do not evidently affect the tensile and thermal properties of the epoxy matrix. This developed healable material with comprehensive properties promises a potentially practical healing system.

Self-Assembled Nanomicellar Formulation of Docetaxel as a Potential Breast Cancer Chemotherapeutic System.

Docetaxel (DTX) is classified as a class IV drug that exhibits poor aqueous solubility (6–7 µg/mL in water) and permeability (P-glycoprotein substrate). The main objective of this study was to construct, characterize, and evaluate docetaxel loaded nanomicellar formulation in vitro for oral delivery to enhance the absorption and bioavailability of DTX, as well as to circumvent P-gp efflux inhibition. Formulations were prepared with two polymeric surfactants, hydrogenated castor oil-40 (HCO-40) and D-α-Tocopherol polyethylene glycol 1000 succinate (VIT E TPGS) with solvent evaporation technique, and the resulting DTX nanomicellar formulations were characterized by proton nuclear magnetic resonance spectroscopy (1H NMR), Fourier Transform Infrared Spectroscopy (FT–IR), X-ray powder diffraction (XRD), and transmission electron microscopy (TEM). Proton NMR, FT–IR, and XRD data indicated that DTX was completely encapsulated within the hydrophobic core of the nanomicelles in its amorphous state. TEM data revealed a smooth spherical shape of the nanomicellar formulation. The optimized formulation (F-2) possessed a mean diameter of 13.42 nm, a zeta potential of −0.19 mV, with a 99.3% entrapment efficiency. Dilution stability study indicated that nanomicelles were stable up to 100-fold dilution with minimal change in size, poly dispersity index (PDI), and zeta potential. In vitro cytotoxicity study revealed higher anticancer activity of DTX nanomicelles at 5 µM compared to the native drug against breast cancer cell line (MCF-7) cells. The LC–MS data confirmed the chemical stability of DTX within the nanomicelles. In vitro drug release study demonstrated faster dissolution of DTX from the nanomicelles compared to the naked drug. Our experimental results exhibit that nanomicelles could be a drug delivery system of choice to encapsulate drugs with low aqueous solubility and permeability that can preserve the stability of the active constituents to provide anticancer activity.

Design and Development of Levodopa Loaded Polymeric Nanoparticles for Intranasal Delivery.

Intranasal delivery is an alternative administration route to deliver levodopa (L-Dopa) to the brain. This drug delivery route offers high drug permeability across the nasal epithelium and rapid absorption into the central nervous system (CNS) while bypassing first-pass metabolism. In this study, we developed a library of polymeric nanocarrier systems for L-Dopa utilising poly(lactic-co-glycolic acid) (PLGA) and chitosan. A total of three PLGA nanoparticles formulations (P1, P2 and P3) were prepared using a modified water-in-oil-in-water (W/O/W) solvent evaporation technique, while four formulations of chitosan nanoparticles (C1, C2, C3 and C4) were prepared by ionic gelation method with sodium tripolyphosphate (TPP) as a cross-linking agent. Upon characterising nanocarriers developed, it was discovered that C2 demonstrated the best results with regard to droplet size (553 ± 52 nm), polydispersity index (0.522), zeta potential (+46.2 ± 2.3 mV), and encapsulation efficiency (82.38% ± 1.63). Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) further corroborated the particle size analysis highlighting that C2 displayed uniform particle size with spherical morphology. Additionally, X-ray diffraction analysis (XRD) revealed that C2 was in an amorphous state while Fourier transform infrared (FTIR) analysis showed that there were no chemical interactions that might change the chemical structure of L-Dopa within the polymeric nanoparticle matrix. Lastly, an in-vivo intranasal study in male Wistar rats showed that the absorption of L-Dopa when formulated as chitosan nanoparticles was significantly enhanced (p < 0.05) by approximately two-fold compared to unmodified L-Dopa. Therefore, this work illustrates that formulating L-Dopa into chitosan nanoparticles for intranasal delivery is a potentially viable formulation strategy to improve the bioavailability of the drug for the treatment of Parkinson’s disease.

Nanocoating and biological evaluation of clindamycin- and rifampicin-loaded nanospheres impregnated Silicone tube for antibacterial application

Two types of nanospheres, namely clindamycin-loaded nanospheres (CN) and rifampicin-loaded nanospheres (RN) were successfully prepared using emulsion solvent evaporation technique. Poly(ε-caprolactone-random-D,L-lactide)-block-poly(ethylene glycol)-block-poly(ε-caprolactone-random-D,L-lactide) (PLEC) was used for preparing nanospheres. CN and RN were coated on an antibiotic-impregnated silicone tube surface by spray coating technique. The formulations of antibiotic-loaded nanospheres (CN and RN) and the amount of spray coating cycles were optimized. Drug loading content, encapsulation efficiency, zeta potential, and size of nanospheres were characterized. The optimal ratios of PLEC to clindamycin; and PLEC to rifampicin were both at 2:1. Drug loading contents of CN and RN were 2.62 ± 0.04% and 7.02 ± 0.02%, respectively. The optimum coating of 90 cycles were provided drug loading contents of 0.0637 ± 0.033 wt.% and 0.0613 ± 0.018 wt.% for rifampicin and clindamycin, respectively. The coating of silicone tube was able to prolong the release of both antibiotics for at least 30 days. Antibacterial activity test was performed using MRSA (ATCC 43300) and S. Epidermidis (ATCC 12228). Moreover, the cytotoxicity of antibiotic-loaded nanospheres coated on silicone tubes was evaluated. The coated silicone tube showed antibacterial activity for at least 28 days and was biocompatible with L929 cells.

Preparation and evaluation of matrix type of transdermal patches containing anti –diabetic drug

The current research aims to formulate and evaluated medicated transdermal patches containing an anti-diabetic drug. A good penetration enhancer would improve drug delivery from various polymer-based transdermal patches. Transdermal patches of the matrix type are made. Using various PVP K30, MC ratios and solvent evaporation techniques. All prepared formulations were tested for weight variation, thickness, drug content, moisture content, moisture uptake, flatness, and in vitro drug release. Bath F3 was optimised formula from all formulation baths shows linear zero order release for 24 hours, with a cumulative percentage of drug diffusion of 87.35% from 4cm2 patches. It has been determined that polymer concentration. When the concentration of PVP K30 increases in the primary layer, the in – vitro diffusion rate increases, and when the concentration of PVP K30 decreases, the drug diffusion decreases. It allows for more controlled drug release from the patch.

DEVELOPMENT EVALUATION AND CHARACTERIZATION OF BUCCAL PATCHES CONTAINING ATENOLOL USING HYDROPHILIC POLYMERS

Objective: The present investigation focused on fabrication and evaluation of atenolol releasing buccal patches comprising mucoadhesive hydrophilic polymers like sodium alginate and tamarind seed polysaccharide with a drug-free backing layer (6 % ethylcellulose). Methods: Solvent evaporation technique being employed in the development of atenolol comprising buccal patches using mucoadhesive hydrophilic polymers. The prepared buccal patch formulations were tested for thickness, weight variation, folding endurance, drug content, moisture content, moisture absorption, % swelling, surface pH, in vitro residence time and mucoadhesion studies. The drug permeation through goat buccal mucosal membrane was conducted with the use of Franz diffusion cell in phosphate buffer saline, pH 6.8 and was subjected to FT-IR and SEM characterization. Stability study was performed as per ICH guidelines. Results: For all the buccal patch formulations, the average weight, thickness, drug content, moisture content, moisture absorption, % swelling, surface pH study exhibited satisfactory results. Out of 7 different buccal patches, the formulation FA-1 revealed the highest mucoadhesive strength (31.36±0.95 g), the force of adhesion (0.31±0.04 N), maximum swelling index (341±0.83 %) and more than 24 h in vitro residence time. The buccal patch formulation FA-1 indicated highest drug permeation (97.51 %) in 24 h and was found to be stable. FT-IR examination confirms lack of drug polymer interaction. SEM investigation reveals a smooth surface of the buccal patch. Conclusion: The developed buccal patches comprising atenolol can be very promising in increasing patient compliance and reducing dosing frequency.

DEVELOPMENT OF NILOTINIB LOADED SOLID LIPID NANOPARTICLES AND OPTIMIZATION BY CENTRAL COMPOSITE DESIGN APPROACH

Objective: In current research, solid lipid nanoparticles (SLN) are formulated for the anticancer drug, nilotinib, to conquer the drawbacks associated with drug including low bioavailability and solubility. Methods: The formulation comprised of tripalmitin (lipid), poloxamer 188(surfactant) and glyceryl palmitostearate (cosurfactant) by solvent evaporation technique. The formulation and process variables of SLN were optimized by experimental design-Central composite design (CCD). The effect of drug to lipid ratio (A), concentration of Poloxamer 188 (B) and concentration of glyceryl palmitostearate(C), on particle size (Y1) and encapsulation efficiency (Y2) of SLN were evaluated. Three batches (F1-F3) of Nilotinib SLNs were formulated by desirability approach and evaluated. Results: The mean size of all the formulations ranged between 187–198 nm, PDI between 0. 291-0.652 and zeta potential between-21.8 to to-24.7 mV indicating the wide range of size distribution and stabiliity of the formulations. The total encapsulation efficiency of SLNs ranged between 85 to 86 %. The SEM analysis revealed the spherical shape of individual particles and PXRD results indicate amorphization of drug in SLN formulation. The drug release was continued for 24 h, indicative of controlled release drug delivery. Conclusion: From the above results it is concluded that the solubility and bioavailability of nilotinib is enhanced.

Biodegradable and Bioactive Carriers Based on Poly(betulin disuccinate-co-sebacic Acid) for Rifampicin Delivery.

This paper describes the preparation and characterization of polymer-drug systems based on polymeric microspheres obtained from poly(betulin disuccinate-co-sebacic acid). The active compound that was coupled to the betulin-based carriers was rifampicin (RIF), an ansamycin drug used in the treatment of tuberculosis. Poly(betulin disuccinate-co-sebacic acid) microspheres were prepared using a solvent evaporation technique from copolymers obtained by polycondensation of betulin disuccinate (DBB) and sebacic acid (SEB). The content of sebacic acid in the copolymers was 20, 40, 60 and 80 wt%, respectively. Small and large rifampicin-loaded microspheres were obtained for each of the copolymers. The initial amount of drug was 10, 30 or 50 wt%, based on the weight of the polymer. Particles obtained in this study were round in shape with diameter in the range of 2–21 μm and of orange to red colour originating from rifampicin. The RIF encapsulation efficacy varied from 7% to 33%. Drug loading varied from 2% to 13% and increased at a higher RIF ratio. The highest degree of drug loading was observed for large particles, in which the initial amount of drug (at the particle preparation stage) was 50 wt%. Microspheres prepared from betulin-based polyanhydrides may have significant applications in drug delivery systems. The concentration of loaded drug was enough to obtain bactericidal effects against reference S. Aureus ATCC 25923 bacteria.

Gentiopicroside PLGA Nanospheres: Fabrication, in vitro Characterization, Antimicrobial Action, and in vivo Effect for Enhancing Wound Healing in Diabetic Rats

PurposeGentiopicroside (GPS), an adequate bioactive candidate, has a promising approach for enhancing wound healing due to its antioxidant and antimicrobial properties. Its poor aqueous solubility negatively affects oral absorption accompanied by low bioavailability due to intestinal/hepatic first-pass metabolism. Our aim in this study is to fabricate GPS into appropriate nanocarriers (PLGA nanospheres, NSs) to enhance its solubility and hence its oral absorption would be improved.MethodsNormal and ODS silica gel together with Sephadex LH20 column used for isolation of GPS from Gentiana lutea roots. Crude GPS would be further processed for nanospheres fabrication using a single o/w emulsion solvent evaporation technique followed by in vitro optimization study to examine the effect of two formulation variables: polymer (PLGA) and stabilizer (PVA) concentrations on the physical characterizations of prepared NSs. Possible GPS-PLGA chemical and physical interactions have been analyzed using Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The optimum GPS-PLGA NSs have been chosen for antimicrobial study to investigate its inhibitory action on Staphylococcus aureus compared with unloaded GPS NSs. Also, a well-designed in vivo study on streptozotocin-induced diabetic rats has been performed to examine the wound healing effect of GPS-PLGA NSs followed by histological examination of wound incisions at different day intervals throughout the study.ResultsThe optimum GPS PLGA NSs (F5) with well-controlled particle size (250.10±07.86 nm), relative high entrapment efficiency (83.35±5.71), and the highest % cumulative release (85.79±8.74) have increased the antimicrobial activity as it exhibited a higher inhibitory effect on bacterial growth than free GPS. F5 showed a greater enhancing impact on wound healing and a significant stimulating effect on the synthesis of collagen fibers compared with free GPS.ConclusionThese findings demonstrate that loading GPS into PLGA NSs is considered a promising strategy ensuring optimum GPS delivery for potential management of wounds.

Poly (vinyl alcohol)/chitosan/sodium alginate composite blended membrane: Preparation, characterization, and water‐induced shape memory phenomenon

AbstractIn this study, we successfully prepared poly (vinyl alcohol)/chitosan/sodium alginate blended (PCS/SA) composite membranes by a simple solution casting method and solvent evaporation technique. The physicochemical properties and effect of different wt% of sodium alginate (SA) on poly (vinyl alcohol)/chitosan (PCS) membranes were systematically evaluated and studied along with its shape memory properties and mechanism. With increased wt% of SA, the crystallinity of PCS/SA membranes reduced significantly. PCS/SA membrane has better thermal stability than pure PVA membrane but is slightly lower than PCS membrane and decreased with higher SA contents. Dynamic mechanical analysis (DMA) study revealed that water act as a stimulus for the shape recovery behavior. The mechanical study showed that PCS membranes with a small amount of SA (0.1 and 0.2 wt%) have a much better elongation at break than other membranes. The swelling ratio, gel contents, and contact angle results concurred with the results of shape memory effect (SME) of all membranes, where the PCS with higher contents of SA possess better and faster shape recovery speed. The above results demonstrate that SA is a potential additive that can be used for water‐induced shape memory applications.

Effect of dye on luminescent and nonlinear optical properties of bis(4-methoxybenzylammonium) tetra-chlorido cadmate (4MBA2CdCl4) perovskite

We report luminescence and optical limiting (OL) applications of pure and doped layered hybrid halide perovskite (LHHP). Rhodamine B (Rh B), an organic laser dye, was doped in bis(4-methoxybenzylammonium) tetra-chlorido cadmate (4MBA2CdCl4). A simple and cost-effective slow solvent evaporation technique was utilized for crystallization of the perovskites. Formation of both pure and doped 4MBA2CdCl4 were confirmed from the X-ray diffraction (XRD) and Fourier transform infrared (FTIR) studies. 4MBA2CdCl4 crystallized as a layered perovskite where organic layers (4MBA+) are sandwiched between the distorted inorganic CdCl4− octahedral layers. The perovskites are thermally stable up to 276 °C and are flexible up to a load of 50 g. Optical absorption of pure perovskite falls in UV region and is highly transparent for visible light. But, inclusion of Rh B reflected a new absorption peak in the visible region. Also, the luminescence under UV excitation of 4MBA2CdCl4 modified due to doping of dye and it exhibit strong golden yellow luminescence. Nonlinear optical (NLO) properties of pure and doped 4MBA2CdCl4 were also studied by Z-scan technique using 785 nm continuous wave (CW) laser. The perovskites exhibited reverse saturable absorption (RSA) and self-defocusing. Further, both perovskites demonstrate optical limiting properties with a low intensity threshold of 0.8 MW/m2. Rh B incorporated 4MBA2CdCl4 exhibit interesting and enhanced photoluminescence and OL behaviours.

Optimisation and evaluation of Gymnema sylvestre extract loaded polymeric nanoparticles for enhancement of in vivo efficacy and reduction of toxicity

Aim This work studies the development and evaluation of Gymnema sylvestre (GYM) extract loaded sustained release polymeric nanoparticles (PNPs) for enhanced bioavailability and reduced nephrotoxicity. The current therapy is associated with the drawbacks of addiction and repeated administration. Method The sustained release PNPs were developed and evaluated for toxicity. PNPs of GYM were prepared by double emulsion solvent evaporation technique utilising Taguchi model and evaluated for physicochemical properties (particle size, zeta potential, entrapment efficiency), in vitro drug release, compatibility, and stability. Further, the bioavailability and in vivo nephrotoxicity studies in diabetic rat model were also carried out. Result The developed optimised nanoparticles were 205.7 ± 1.20 nm in size, −40.68 mV zeta potential, compatible, and stable in nature with improved entrapment efficiency (67.1 ± 0.2%) and sustained release. Moreover, nanoparticles were found to lower the blood glucose level in single as well as multiple doses. Results of in vivo study indicated that GYM-NPs increased the phosphorylase activity and thus enhanced insulin secretion. Furthermore, the nanoparticles were free from toxicity, which was confirmed by the estimation of kidney biomarker. Conclusion The nanoparticles increased the bioavailability of GYM extract and have a great potential for the treatment of diabetes in reduced dose, and so these can be potential candidates for treating diabetes.