Ultra-thin foldable transparent electrodes composed of stacked silver nanowires embedded in polydimethylsiloxane

We have prepared an ultra-thin flexible transparent conductive electrode with high folding endurance composed of randomly arranged silver nanowires (AgNWs) embedded in polydimethylsiloxane (PDMS). A simple preparation method was performed to connect a glass substrate coated with a AgNW network and a glass substrate coated with PDMS. The glass substrate was then removed after the PDMS solidified, and the AgNW–PDMS composite film was peeled off. Moreover, the problem of the high contact resistance caused by the random arrangement of AgNWs was solved by the local joule heat generated by applying voltage to both sides of the AgNW–PDMS composite structure to weld the overlapping AgNWs. The sheet resistance (Rs ) of AgNW–PDMS composite films with different AgNW deposition concentrations decreased by 46.4%–75.8% through this electro-sintering treatment. The embedded structure of the AgNW–PDMS composite ensures better voltage resistance and environmental stability under high temperature and humidity conditions compared with a AgNW network attached to a glass substrate. Additionally, the substrate-free, excellent elasticity and high resilience characteristics resulted in the Rs value of the same composite electrode only increasing by 2.9 ohm/sq after folding four times. The advantage of the metal thermal conductivity makes the joule heat generated by electric injection rapidly diffuse and dissipate in the AgNW-based transparent heater with faster response time and smaller voltage drive than indium tin oxide.

Proposal of the Measurement Conditions for Hanji–Determination Folding Endurance

This study aims to optimize the measurement conditions of handmade Hanji paper to reduce the time required for measurement while meeting folding endurance standards, for various basis weights. Thirteen types were selected, including 12 types of Hanji with grammages of 17 g/m2, 30 g/m2, and 45 g/m2, and one type of 75 g/m2 copy paper, and 24 sheets were prepared in the laid and chain directions. Subsequently, folding endurance experiments at different load (14.72 N, 9.81 N, 4.91 N) and specimen width conditions (15 mm, 10 mm, 5 mm) were performed, using a 4-MIT folding endurance tester. The results showed that, for specimen widths of 15 mm and 10 mm under a load of 4.91 N, the folding endurance falls within the reference range (10∼10000 times). In particular, reduced folding endurance range and measurement time were observed at a width of 10 mm under a load of 4.91 N. Moreover, the endurance trend lines based on the average values of load and specimen width ranges enabled the prediction of the folding endurance within those ranges, according to the decreasing slope. Furthermore, for a specimen width of 15 mm under a load of 4.91 N, the folding endurance in the comparison group (35 to 17723 times) significantly exceeds the upper limit of the reference range (10∼10000 times). Therefore, the measurement conditions of 4.91 N with a specimen width of 10 mm are proposed.

Formulation and Evaluation of Transdermal Patch of Thiochochicoside

The aim of the study is to formulate and evaluate transdermal patches of Thiocholchicoside In the present study, matrix type were prepared by moulding techniques. This mode of drug delivery is more beneficial for chronic disorders such as Rheumatoid arthritis which require long term drug administration to maintain therapeutic drug concentration in plasma. Transport of drugs or compounds via skin is a complex phenomenon, which allows the passage of drugs or compounds into and across the skin. In the present work an attempt has been made to formulate and evaluate the transdermal patches of Thiocholchicoside using various blends of polymer. The polymeric combinations EC/PVP and EC/HPMC used for the formulation of transdermal patches showed good film forming property. The patches formed were thin, flexible, smooth and transparent. The weight variation tests showed less variation in weight and suggesting uniform distribution of drug and polymer over the mercury surface. The thicknesses of the transdermal patches were found to increase on increasing concentration of hydrophilic polymers like PVP and HPMC.All the patches showed good flexibility and folding endurance properties. The result suggests that the formulations with increased hydrophilic polymer concentration showed long folding endurance. The moisture content in the patches was found to be low and formulations with more hydrophilic polymer concentrations showed more percentage moisture content. The in-vitro drug release studies showed that formulations TDP2, TDP3, TDP4, and TDP5 with increased concentration of hydrophilic polymer showed rapid release. The drug content analysis showed minimum variations suggesting uniform distribution of drug.

Characterization of bilayered matrix-type mucoadhesive buccal films containing tizanidine hydrochloride and piroxicam

Purpose: To formulate and characterize tizanidine hydrochloride (TZN) and piroxicam (PRX)-loaded bilayer mucoadhesive buccal films with an intention to improve the bioavailability and patient compliance in pain management.Methods: Bilayer buccal films were prepared by solvent evaporation technique using hydroxypropyl methylcellulose (HPMC) 15cps and polyvinylpyrrolidone (PVP K30 as immediate release (IR) layer forming polymers and HPMC K15 M, PVP K 90 along with various muco adhesive polymers (Carbopol P934, sodium alginate, etc), as sustained release (SR) layer forming polymers. The prepared films werecharacterized for thickness, weight variation, folding endurance, surface pH, swelling index,mucoadhesive strength, in vitro residence time, in vitro drug release, ex vivo permeation and drug release kinetics.Results: The prepared films were of largely uniform thickness, weight and drug content. Moisture loss (%) and folding endurance were satisfactory. Surface pH was compatible with salivary fluid. Disintegration time was 85 s for F1 and 115 s for F2 of IR films. In vitro dissolution studies showed 99.12 ± 1.2 % (F1) and 90.36 ± 1.8 % (F2) were released in 45 min. Based on the above results, F1 was chosen as the optimum formulation to be combined with SR layer of TZN. Amongst the SR layers of TZN in vitro drug release. The findings show that of F2 was 98.38 ± 0.82 % and correlated with ex vivo release. Drug release followed zero order release kinetics and mechanism of drug release was non-Fickian type diffusion. In vitro residence time was greater than 5 h.Conclusion: The findings show that the bilayer buccal films demonstrate the dual impact of deliveringPRX instantly from the IR layer, with good controlled release and permeation of TZN from the SR layer, thus providing enhanced therapeutic efficacy, drug bioavailability and patient compliance.

PREPARATION AND CHARACTERIZATION OF TRIFLUOPERAZINE LOADED TRANSDERMAL PATCHES FOR SUSTAINED RELEASE

Objective: The purpose of the present study was to formulate and evaluate the polymeric transdermal delivery system of antipsychotic drug Trifluoperazine (TFP) for sustained drug release. Methods: A transdermal patch loaded with (TFP) was formulated by solvent casting technique. Polyvinyl pyrrolidone (PVP) K-30 and ethyl cellulose (EC) was used as a polymeric matrix with different ratios. Di n-butyl phthalate was used as a plasticizer. The parameters such as thickness, folding endurance and weight variation of the prepared patches were studied. The interaction study by attenuated total reflectance-infrared (ATR-IR) spectroscopy, X-ray diffraction and thermal analysis by differential scanning calorimetry (DSC) were performed. In vitro drug release study was performed by modified paddle over-disc technique. Results: The infrared spectroscopic study confirmed the absence of any chemical interaction between TFP and selected polymers. All the prepared formulations showed folding endurance values ranging from 130-162 and a satisfactory drug loading of 90-95%. In in vitro drug release study, formulations PE-3 and PE-4 exhibited a sustained and stable cumulative release of 54 % and 48% respectively, at the end of 24 h. The DSC and XRD analysis proved the partial conversion of the drug from crystalline to amorphous form when integrated into the polymeric matrix. Conclusion: The prepared transdermal formulations using polymers PVP and ethyl cellulose demonstrated their ability to sustain the release of TFP. The developed formulation could be exploited for multiday therapy of TFP for the effective treatment of schizophrenia with a simplified dosing regimen and enhanced patient compliance.

Development and Evaluation of Fast dissolving Film of Fluoxetine hydrochloride

The intention of the present study was to formulate the oral dispersible film of Fluoxetine hydrochloride using pullulan as a polymer and to evaluate it with the different parameters. The drug-excipients studies were carried out in order to determine any type of incompatibilities by using Fourier transmission infrared spectroscopy (FT-IR). The oral dispersible films were prepared using solvent casting method using pullulan as a polymer. Glycerin was used as a plasticizer. The prepared films were evaluated for the parameters like physical appearance, thickness, folding endurance, In-vitro disintegration, mechanical properties, surface pH, drug content uniformity, taste evaluation, In-vitro dissolution test and stability study. The X5 formulation was found to be stable and appropriate in its evaluation parameters than compared to other formulations. The folding endurance was found to be 259±2.53, disintegration time was found to be 04±0.69, thickness was found to be 0.081±0.003, tensile strength was found to be 5.55, the % elongation was found to be 27.50, the maximum percentage drug release was found to be 95.80% in 30 minutes. The drug content was found to be 99.86 with surface pH of 6.8. In the stability studies of the formulation the product was found to be stable for 90 days. The oral dispersible film is simple to administer and very much effective for the patients and the prepared film of fluoxetine hydrochloride proves to be potential candidate for safe and effective oral dispersible drug delivery.

Comparative assessment of the pulping potentials of soda and mea processes for the development of paper-pulp from sugarcane bagasse

Pulping trials were carried out using MEA and the soda process comparing their pulping potentials. The operating conditions such as the concentration of the cooking liquor (50%, 75%, 100%) for MEA and (10%, 15%, 20%) for NaOH, the maximum cooking temperature (150oC, 160oC, 170oC) and cooking time (60, 90, 120minutes) for both processes were investigated systematically to establish optimal pulping conditions. The agro-biomass used in this investigation is Sugarcane Bagasse viewed as alternative raw material for pulp and paper production. The lignin content of Bagasse (19.5%) was low; indicating that Bagasse should be easier to pulp. The optimum cooking conditions (independent variables) for MEA pulping were 75% MEA concentration, 150oC cooking temperature and 90 minutes cooking time. Excel 2013 was used to analyze the effect of independent variables on yield of bagasse pulp and properties of furnished paper from MEA process in comparison with the Soda process which include tear index, tensile index, burst index and folding endurance with errors less than 15% in all cases. The Kappa number range (12.7-16.9), viscosity (270-870 ml/g) and brightness (62.1-93.2%) of bagasse pulp are appropriate for high-brightness printing and writing papers. The physical properties of furnished paper, tear index (13.4 mN.m2/g), tensile index (71Nm/g), Burst index (4.8 KN/g) and folding endurance (82) recommend the cellulosic pulp from Sugarcane Bagasse obtained from the MEA process for strengthening the virgin fiber in recycled papers and also for developing certain types of printing and packaging papers. Due to the awareness towards the negative impact of kraft mill’s effluent to the environment recently, soda pulping started to regain its popularity among the pulp mills especially non-wood based pulp mills. MEA process is more economically attractive given its high pulp yield, despite the significant increase in chemical demand for bleaching. MEA pulping is a good alternative to soda pulping furnishing high pulp yield with less cooking temperature, i.e. 150oC, thereby saving a considerable amount of energy with less odoriferous pollutants and pollution load associated with the soda process.

Wood fiber-reinforced polylactic acid sheets enabled by papermaking

Polylactic acid is a biodegradable thermoplastic polyester derived from renewable polysaccharides. In this work, softwood fibers were used to reinforce the paper sheet made from polylactic acid fibers, thus addressing the challenges regarding low density, rough surface, and weak strength. The impact of wood fibers and calendering on the physical properties (density, roughness, tensile strength, and folding endurance) of the composite paper were identified. Furthermore, the morphology of papers with different fiber contents and those that had been calendered was characterized with a scanning electron microscope. The use of wood fibers resulted in the improvement of the physical properties of the polylactic acid paper, and the enhanced refining of wood fibers had a favorable role in improving paper density, smoothness, and mechanical strength. The tensile index increased 37.9% when the beating degree of wood fibers increased from 25 to 60 °SR. After calendering, the density, smoothness, tensile strength, folding endurance, and air barrier property of the paper were improved 60.2%, 45.8%, 15.5%, 148.1%, and 79.4%, respectively. The calendering-based papermaking process involving the combined use of wood fibers and polylactic acid fibers would be a promising strategy for designing composite materials for tailorable end-uses.

Development, Evaluation, and Molecular Docking of Oral Dissolving Film of Atenolol

The development of oral dissolving film (ODF) of atenolol is an attempt to enhance convenience and compliance for geriatric patients suffering from hypertension. Film former is the most essential component in ODF that determines the physical characteristic and drug release. In this study, three different types of film former including HPMC E5 4% (w/v), 5% (w/v), CMC-Na 3% (w/v), 4% (w/v), and Na-alginate 2.5% (w/v), 3% (w/v) were optimized in Formula 1 (F1) to Formula 6 (F6), respectively. A solvent casting method was employed to develop ODF of atenolol. The films formed by HPMC E5 produced a smooth and flexible surface, whereas CMC-Na and Na-alginate produced gritty textured films. Satisfactory results were obtained from several physical parameters such as film thickness, folding endurance, swelling index, and disintegration time. The homogeneity, drug content, and dissolution properties of ODF with HPMC exhibited better characteristics than the other formulas. Formula 1 exhibited the highest drug release compared to the other ODFs. The molecular docking results showed that there was a hydrogen bonding between atenolol and film formers which was also supported by the FTIR spectrum. The findings of this study suggest that HPMC E5 is the most favorable film former for ODF of atenolol.