Solvent Diffusion Research Articles

A model for the contraction kinetics of cytoskeletal gel slabs

Cytoskeletal gels are engineered prototypes that mimic the contractile behavior of a cell in vitro. They are composed of an active polymer matrix and a liquid solvent. Their contraction kinetics is governed by two dynamic phenomena: mechanotransduction (molecular motor activation) and solvent diffusion. In this paper, we solve the transient problem for the simple case of a thin gel slab in uniaxial contraction under two extreme conditions: motor-limited or slow motor (SM) activation regime, and diffusion-limited or fast motor (FM) activation regime. The former occurs when diffusion is much faster than mechanotransduction, while the latter occurs in the opposite case. We observe that in the SM regime, the contraction time scales as t/t0∼(λ/λ0)−3, with t0 being the nominal contraction time, and λ and λ0 being the final and initial stretches of the slab. t0 is proportional to 1/w˙, where w˙ is the average mechanical power generated by the molecular motors per unit reference (dry polymer) volume. In the FM regime, the contraction time scales as t/t1∼(1−λ/λ0)2, with t1 being the nominal contraction time, here proportional to the ratio L2/D, where L is the reference (dry polymer) thickness, and D is the diffusivity of the solvent in the gel. The transition between the SM and FM regimes is defined by a characteristic power density w˙∗, where w˙≪w˙∗ gives the SM regime and w˙≫w˙∗ gives the FM regime. Intuitively, w˙∗ is proportional to D/L2, where, at a given power density w˙, a thinner gel slab (smaller L) or including smaller solvent molecules (higher D) is more likely to be in the SM regime given that solvent diffusion will occur faster than motor activation.

Visible-light excitable thermally activated delayed fluorescence from hydrogen-bonded D-A aromatic N-heterocycle/polymer material and the application for anti-counterfeiting

Thermally activated delayed fluorescence (TADF) polymer materials have shown promising potential in the optical information encryption. However, these materials still face challenges related to complex and toxic fabrication processes for guest molecules, transitional metal doping, expensive catalysts, toxic organic solvents, and the requirement of UV light excitation. To address these challenges, we present the facile synthesis of a crystalline intramolecular hydrogen-bonded D-A aromatic N-heterocycle crystal (DI-1) with suitable energy splitting between singlet and triplet excited states (ΔEST), which is achieved using a slow solvent diffusion method with ethanol as the resolvent. Furthermore, we propose a green and straightforward host-guest doping strategy by coupling DI-1 with water-soluble PVA (DI-1/PVA-0.3 wt%) through a water-promoted dispersion method. The DI-1/PVA-0.3 wt% composite exhibits high quantum efficiency and long TADF lifetime when excited by visible light at room temperature. These desirable properties are attributed to the appropriate ΔEST of DI-1 with D-A structure and the establishment of a hydrogen bonding network between DI-1 and PVA. Additionally, we demonstrate the facile fabrication of an anti-counterfeiting 2D code pattern using environmentally friendly and cost-effective screen printing techniques with DI-1/PVA-0.3 wt%. This pattern can be easily deciphered using white light, offering insights into commercial production for dual optical and digital security protection. Our work provides a strategy for the development of TADF materials that can be excited by visible light, showcasing their potential application in information encryption and decryption.

Formulation and Evaluation of Miconazole Nanocapsules

Using the emulsion solvent diffusion technique, the current study's goal was to create and analyze miconazole nanocapsules. Ethyl cellulose as well as HPMC nanocapsules were used to fill the miconazole, which has been produced using the emulsion solvent diffusion method. The FTIR data showed that the miconazole nanocapsules filled with ethyl cellulose nanocapsules were stable and that there was no drug-polymer interaction. To determine whether there is no incompatibility in the formulation, compatibility investigations like FTIR & DSC were utilized. The morphological particle size of miconazole nanocapsules is assessed using SEM. This complete formulation codes for the nanocapsules were F1 to F8. The optimum formulation F6's in vitro dissolution rate was found to be 75.22 percent. A variety of mathematical models, including the zero order, first order, Higuchi matrix, and Korsmeyer peppas model, were fitted to the data on drug dissolution in vitro. The model that the miconazole nanocapsules use has R2 values of 0.937, 0.399, 0.899, and 0.785 and m values of 1593, 0.061, 11409, and 2.560. The Nanocapsules released the medication over 45 minutes. The ethyl cellulose and HPMC nanocapsules that contain miconazole were created under ideal circumstances and exhibit good release properties.

Magnetic Aggregation-Induced Bone-Targeting Nanocarrier with Effects of Piezo1 Activation and Osteogenic-Angiogenic Coupling for Osteoporotic Bone Repair.

Osteoporosis, characterized by an imbalance in bone homeostasis, is a global health concern. Bone defects are difficult to heal in patients with osteoporosis. Classical drug treatments for osteoporotic bone defects have unsatisfactory efficacy owing to side effects and imprecise delivery problems. In this study, a magnetic aggregation-induced bone-targeting poly(lactic-co-glycolic acid, PLGA)-based nanocarrier (ZOL-PLGA@Yoda1/SPIO) is synthesized to realize dual-targeted delivery and precise Piezo1-activated therapy for osteoporotic bone defects. Piezo1 is an important mechanotransducer that plays a key role in regulating bone homeostasis. To achieve dual-targeting properties, ZOL-PLGA@Yoda1/SPIO is fabricated using zoledronate (ZOL)-decorated PLGA, superparamagnetic iron oxide (SPIO), and Piezo1-activated molecule Yoda1 via the emulsion solvent diffusion method. Bone-targeting molecular mediation and magnetic aggregation-induced properties can jointly and effectively achieve precise delivery to localized bone defects. Moreover, Yoda1 loading enables targeted and efficient mimicking of mechanical signals and activation of Piezo1. Experiments in vivo and in vitro demonstrate that ZOL-PLGA@Yoda1/SPIO can activate Piezo1 in bone defect areas of osteoporotic mice, improve osteogenesis through YAP/β-catenin signaling axis, promote a well-coordinated osteogenesis-angiogenesis coupling, and significantly accelerate bone reconstruction within the defects without noticeable side effects. Overall, this novel dual-targeting nanocarrier provides a potentially effective strategy for the clinical treatment of osteoporotic bone defects.

Design, Development and Evaluation of Nanosponges Loaded Topical Gel for Rejuvenation of Skin

The study aimed the development of nanosponges was the choice due to the numerous advantages of this novel technology over the others. Rutin was chosen as it has excellent antioxidant potential. The compatibility study was performed using Fourier transform infrared (FTIR) and there was no interaction found. The optimization study was brought off by Design expert software (version.13). Nanosponges were prepared by emulsion solvent diffusion method. The prepared sponges were brimmed in a night gel formulation for their suitable delivery to the skin. The prepared nanosponges were evaluated for various parameters such as particle size analysis, entrapment efficiency and zeta potential which were found in the acceptable limit. In-vitro permeation study was carried out using Franz-diffusion cell and the cumulative percent drug permeation was found to be 69 to 84.5% in 30 hours. A gel formulation was prepared using rutin-loaded nanosponges and studied for various parameters such as pH, viscosity, and extrudability for various combinations using NS-4. Ex-vivo drug diffusion study reveals that the night gel took 300 minutes for 78.26 to 94.16% permeation. The IC50 values of the flavonoid combination, NS-4 was found to be 54.70, 52.76, and 51.65 μg/mL in the different in-vitro models viz. DPPH, when compared to that of the standard ascorbic acid. Conclusively, the objective of delivery of rutin using nanosponges as carriers for the target delivery was achieved by NS-4 formulation and successfully delivered as night gel for skin rejuvenation.

Nanogel: Types, Methods of Preparation, Limitation, Evaluation and Application – A Systematic Review

Nanogels combine the characteristics of nanomaterials with hydrogels. To meet the expanding demands from various areas, a sizable number of nanogels have been designed and manufactured using the emulsion solvent diffusion nano precipitated method, emulsion evaporation of the solvent method, reverse micellar method and modified diffusion emulsification method. Thermosensitive nanogel, pH-sensitive nanogel, ultrasound-sensitive magnetic response, response to multiple stimuli, chain transfer polymerization, photo-induced crosslinking polymerization and modifications for active targeting are the types of nanogels based on response towards stimuli and polysaccharide, chitosan, pullulan, hyaluronic acid, alginate, cyclodextrin, gum acacia, protein are used to prepare nanogel. Nanogels have considerable potential and novelty within the biomedical sector due to their uniformity, adjustable dimensions, little toxicity, resilience in the presence of serum, and capacity for responsive behavior with a comparatively high drug encapsulation capacity. Nanogels have considerable potential in bioactive substance delivery, organ targeting, and chemotherapy. The article highlighted the preparation, types, evaluation and applicability of nanogel as a targeted delivery system.

Evaluation of Insulin Loaded Microspheres for Oral Delivery

Microsphere-based colon-specific medication delivery devices should improve bioactive chemical administration and residence periods. In the first step, insulin microspheres were made using Eudragit RL 100 and L-100 by quasi-emulsion solvent diffusion. Microspheres were made since prior research showed that colon tissue macrophages could take up drug carrier systems with a molecular weight of 956 m or less. The uptake process allows accurate medication delivery to the specified site. Microspheres’ longer residence time than conventional drug delivery methods may allow dosage reduction and therapeutic efficacy. Because microspheres are permeable, they may be compacted and used to make stronger tablets. Thus, the CPDRS1 formulation performs well, enabling insulin delivery via an anti-diabetic microsphere. Drug-polymer ratio affects microsphere size and form. Variations in emulsifying agent amounts affect microsphere sizes and manufacturing yield. Using appropriate polymer and emulsification agent concentrations improves insulin-loaded Eudrajit L microsphere (Eudrajit RL) formulation and manufacturing yield

In Situ Transesterification from Soybean Seed Using Mechanochemical Methods toward Producing Biodiesel.

The research and development of new routes of biodiesel synthesis have been increasingly in line with the principles of green chemistry. In this sense, mechanochemistry is a promising technique, able to ally the energetic potential with reductions in the use of solvents and steps of treatment of the sample and the purification of the product. To date, this is the first work using mechanochemistry directly in extracting soybean oil from its seed and the in situ transesterification reaction by applying a reactive soybean oil extraction process. The presence of n-hexane was studied in different molar proportions (relative to the oil content), and a low solvent consumption in a 3:1 ratio was adopted. Mechanochemistry favored oil diffusion in the n-hexane solvent, resulting in a mean triglyceride content equal to 90%, against 66% obtained in the tests without spheres in the planetary ball mill. The catalyst content was also evaluated, and 4% NaOH (weight, concerning the oil) was the concentration that presented less residue of nontransesterified glycerides in the samples for ethyl ester preparation. Additionally, the protein content was determined on the residual soybean cake, with no loss of nutritional potential when subjected to the mechanochemical process.

"Optimizing Pharmaceutical Formulations: Advancements in Nanosuspension Pre-Formulation to Enhance Solubility and Bioavailability of Active Agents"

This study aimed to enhance the bioavailability of a poorly water soluble drug by developing a nanosuspension through an innovative formulation method. The nanosuspension was produced with meticulous attention to the materials reliability and excellent quality. Nepafenac was characterised in the pre-formulation study by establishing its melting point, solubility in different solvents, organoleptic properties, and creating a calibration curve. We utilised UV spectroscopy to determine the maximum wavelength (?max) of Nepafenac and construct a standard calibration curve in ethanol. To ensure the compatibility of the medicine with the polymers (Pluronic F127 and HPMC E 5), Fourier Transform Infrared Spectroscopy (FTIR) was utilised for drug interaction analysis. The nanosuspension was produced using the solvent diffusion approach. The effect of different concentrations of Poloxamer 407 and HPMC E 5 on the formulation's effectiveness was investigated experimentally using a 32 complete factorial design. We used Response Surface Methodology (RSM) and statistical analysis to enhance the formulation concerning in vitro release, particle size, and viscosity. The pre-formulation characteristics of Nepafenac met the standards outlined in the Pharmacopoeial regulations. The maximum absorption wavelength (?max) of Nepafenac was confirmed by UV spectroscopy, and a reliable calibration curve was created. The FTIR analysis showed no chemical interaction between the medicine and polymers. RSM and experimental design indicated that Poloxamer 407 and HPMC E 5 had a substantial impact on the performance of the nanosuspension. Analysis of variance (ANOVA) confirmed the model and parameters that influence controlled drug release percentage, particle size, and viscosity. Optimal conditions for enhancing drug delivery and reducing particle size were determined by the analysis of contour and response surface plots. The optimal parameter values, as indicated in the desirability plots, closely matched the anticipated values. The experimentation confirmed the viability and effectiveness of the nanosuspension formulation generated based on the RSM findings.

Review on Microspheres: A Novel Approach in Drug Delivery System

A well-designed controlled drug delivery system has the potential to address the limitations of conventional drug therapy and enhance the therapeutic effectiveness of a drug. Microspheres, which are characterized by their particle size being 1-1000 μm, are considered a novel and controlled drug delivery system. The spherical shape of microspheres contributes to their advantageous properties. This review focuses on the utilization of microspheres as a novel drug delivery system. These characteristics can be modified by altering the materials, methods, polymers, or techniques used in the production of microspheres. Microspheres are composed of natural or synthetic polymers. They are utilized in drug delivery systems to achieve prolonged or controlled drug release, enhancing bioavailability, stability, and action at specific sites at predetermined rates. Microspheres can be manufactured using various natural or synthetic materials. Different types of microspheres include bio adhesive, magnetic, floating, radioactive, polymeric, biodegradable polymeric, and synthetic polymeric microspheres. These microspheres are prepared using methods such as spray drying, solvent evaporation, single emulsion technique, double emulsion technique, phase separation coacervation technique, spray drying and spray congealing, solvent extraction, and quasi-emulsion solvent diffusion. Microspheres have a wide range of applications and evaluation parameters. Keywords: Microsphere, Novel Drug Delivery, Types of Microspheres, Methods of preparation Microspheres, Biodegradable.

Composite polymeric microsponge‐based long‐acting gel formulation for topical delivery of mupirocin

AbstractTopical delivery of medicaments in a controlled manner is still a promising area of research. Drug‐containing dammar gum‐ethyl cellulose composite microsponge loaded gel formulation (D‐MSPG) was developed for controlled topical delivery of mupirocin. The drug‐loaded microsponges (D‐MSPs) were formulated by the quasi‐emulsion solvent diffusion method and were evaluated for morphology, particle size distribution, entrapment efficiency, thermal properties, and crystallinity. The optimized D‐MSPs (entrapment efficiency 91.5 ± 4.0% and particle size of 55.15 ± 2.9 μm) were dispersed in carbopol 934 gel (D‐MSPG). The final product was characterized for pH, viscosity, texture, spreadability, consistency, syneresis, in vitro drug release, and ex vivo skin penetration study. A comparative study with marketed formulation was performed. For optimized gel formulation (G4), drug content was 104.19 ± 1.68%, and drug release was 84.19% after 24 h. The pH of the optimized gel was observed to be 6.05 ± 0.04. Viscosity of the optimized gel formulation was found to be 1212.15 ± 434.85 mPa‐s at 50 s−1. The steady‐state flux (J) in ex vivo skin permeation was observed to be 53.96 μg cm−2 h−1 and the permeability coefficient was 2.69 cm/h for the optimized gel formulation. According to the findings, the D‐MSPG‐based formulation strategy can act well to prolong the topical delivery of mupirocin or similar drug molecules.

Formulation, optimization, and in-vitro evaluation of polymeric microsponges for topical delivery of vanillin

The development of ethylcellulose-based polymeric microsponges for the topical delivery of therapeutic agents has attracted the interest of pharmaceutical scientists around the globe in recent years. This work represents preparation, optimization (using Box–Behnken design [BBD]), and characterization (in-vitro and ex-vivo) of ethylcellulose microsponges loaded with vanillin for effective topical delivery to treat wounds. Vanillin-ethylcellulose microsponges were prepared by using quasi-emulsion solvent diffusion and optimized formulation (F9) (containing 100 mg ethylcellulose, 10 mL dichloromethane, 100 mg vanillin, and 90 mg polyvinyl alcohol) developed showed particle size (90.3 ± 2.9 µm), high entrapment of vanillin (79.0 ± 2.8%), and optimum colloidal properties (zeta potential = −37.91 ± 2.44 mV; polydispersity index (PDI) = 0.224 ± 0.23). Optimized formulation extended the release of vanillin (96.68 ± 3.11%) in-vitro for 24 h. Vanillin-ethylcellulose microsponges (F9) dispersed in Carbopol 940 gel showed limited ex-vivo skin permeation (steady-state flux, JSS = 243.7 ± 6.2 µg/cm2/h) and higher skin retention (82.46 ± 6.74%) for 24 h in pig ear skin compared to plain vanillin Carbopol 940 gel (steady-state flux, JSS = 1350 ± 10.8 µg/cm2/h, skin retention = 33.66 ± 4.53%). Results of confocal laser scanning microscopy (CLSM) of Vanillin-ethylcellulose microsponges (F9) Carbopol 940 gel revealed accumulation of microsponges in the stratum corneum layer of skin as a depot. Microsponges-based Carbopol 940 gel also displayed excellent in-vitro antibacterial activity (zone of inhibition = 24.2 ± 1.3 mm) against Staphylococcus aureus for 24 h compared to plain vanillin Carbopol 940 gel (zone of inhibition = 10.30 ± 1.2 mm) that was considered good for its wound healing activity. Therefore, developed vanillin-loaded ethylcellulose microsponges could be effectively used in the treatment of wounds by reducing side effects associated with vanillin and promoting its localized delivery in Carbopol 940 gel form.

Uncovering dissolution behavior and thermodynamic properties of metronidazole benzoate in twelve mono-solvents by experiments and molecular simulation

In this study, metronidazole benzoate (MBZ), a nitroimidazole antibiotic, was selected to measure the solubility in 12 solvents by the gravimetric method in the temperature range of 278.15 K to 323.15 K. The intermolecular interactions dominated by H···H and O···H contacts in the solid phase were determined using Hirshfeld surface analysis (HS). Subsequently, molecular simulations involving molecular electrostatic potential surface (MEPs), hydrogen binding energy (EHB) and mean square displacement (MSD) revealed the effect of the solvent polarity, hydrogen bonding and diffusion process on the dissolution behavior of MBZ. Furthermore, six thermodynamic models, all with values of ARDs less than 5 %, were successfully correlated with the experimental solubility results. The Apelblat model achieved the best fitting. Based on the NRTL models, relevant thermodynamic parameters were obtained, indicating that the dissolution process of MBZ in various solvents is spontaneous and entropy-driven. In the measured temperature range, the solubility of MBZ in different solvents increased from 4-times to 25-times as the temperature changed, which provided an important theoretical basis for the industrial production of MBZ.

Formulation and Evaluation of Terbinafine Hydro-chloride Loaded Microsponges Gel

Background: Microsponges are porous, polymeric microspheres employed for sustained topical treatment. They may modify the release pattern, lessen adverse effects, and improve stability. Terbinafine HCL is a fungicidal allylamine derivative with a wide range of antifungal activity. It is used to treat various skin disorders like ringworm, athlete’s foot, and jock itch. Objective: The aim of the current study focuses on the development of terbinafine HCL microsponges that will release the drug in a sustained pattern to prevent side effects and then put those microsponges into a gel. Method: The quasi-emulsion solvent diffusion method was employed to develop Microsponges by using various drug: polymer ratios. Result: The results of the FTIR spectra showed that there was an absence of interaction between Terbinafine HCL and the excipients. Based on the evaluation parameter, it was found that batch MS3 showed the highest entrapment efficiency of 86.32%. Polymer EC showed better results. Microsponges and Microsponges gel showed sustained release of drug till 8 and 10 hours, respectively. The gels were shown to be stable throughout a wide temperature range, according to the stability studies. Conclusion: It was concluded that the Microsponges release the drug in a stained manner. The production process for microsponge technology has the potential to improve patient compliance with terbinafine hydrochloride microsponge gel.

Targeted delivery of essential oils of Salvia officinalis L to AGS cancer cells using PLA-spermine-PEG-FA

The MTT test was used in this study to evaluate anticancer potential of Salvia officinalis L's essential oil on AGS cells. The results showed that the Salvia officinalis L's essential oil has high potential anticancer activity against AGS cells. To improve the solubility of the essential oil and its targeted administration to AGS cells, poly lactic acid-spermine-poly ethylene glycol-folic acid (PLA-Spermine-PEG-FA) (FPSP) was utilized. For this purpose, Salvia officinalis L's essential oil and silver nanoparticles were encapsulated into the PLA-Spermine-PEG-FA (FPSP) using the solvent diffusion technique. Then, using transmission electron microscope (TEM) and dynamic light scattering (DLS), respectively, morphology, zeta potential, as well as average particle size characteristics of the nanoparticles were evaluated. The FPSP/essential oil nanoparticles (FPSP/EO) were spherical in shape and had an average particle size of 200–300 nm. The mean particle dimensions for both PSP/silver/EO and FPSP/silver/EO nanoparticles assemblies are measured at 236.52 ± 22.64 nm and 248.95 ± 28.17 nm, respectively. The results showed that the zeta potential values for PSP/silver/EO and FPSP/silver/EO were −18.3 ± 0.7 mV and −20.6 ± 1.3 mV, respectively. The results of this test showed that FPSP/Silver/EO significantly reduced the percentage of AGS cell viability better than EO and PSP/Silver/EO. The best treatment in this experiment was FPSP/Silver/EO at a concentration of 50 μL/mL and time 72 h. The minimum value of IC50 in FPSP/Silver/EO was observed as 21.11 μL/mL in 72 h.

Influence of Technological Process Parameters on Microcapsulation of Substances with Unsatisfactory Technological Properties

Introduction. The article presents the results of a study of the influence of parameters of microcapsulation on the properties of microcapsules obtained by diffusion of an emulsion solvent. The results obtained made it possible to establish optimal parameters of the process, such as the mixing speed, the type of mixing device, the volume of the aqueous phase, the concentration of the polymer in the oil phase, the ratio of medicinal substance : polymer, temperature conditions.Aim. The aim of the work was to study the influence of the parameters of the microcapsulation process on the properties of microcapsules obtained by diffusion of an emulsion solvent.Materials and methods. Ibuprofen was used as a model substance for microcapsulation. Eudragit® RS 100 was chosen as the carrier polymer. To assess the shape and nature of the microcapsule surface, a microscope Levenhuk D80L LCD was used, and the size of microcapsules was determined using a laser particle analyzer Microsizer 201C (VA Instalt, Russia).Results and discussion. The influence of the parameters of the microcapsulation process on the properties of ibuprofen microcapsules as a model substance obtained by diffusion of an emulsion solvent has been studied. The optimal parameters of the technology are established, the dependences between the critical parameters of microcapsulation and the properties of the resulting microcapsules are determined.Conclusion. In the course of the study, the choice of technological parameters of microcapsulation by diffusion of an emulsion solvent was proposed and justified. The experimental data obtained on the example of ibuprofen as a model substance will be used as the basis of the experiment when preparing microcapsules based on other substances soluble in organic solvents.

DEVELOPMENT OF ACECLOFENAC LOADED MICROSPONGE GELS: A STATISTICAL QUALITY BY DESIGN (QBD) APPROACH TOWARDS OPTIMIZATION AND EVALUATION

Objective: The current research aims to deliver Aceclofenac in a controlled manner through a microsponges-loaded drug delivery system for the treatment of inflammation. Methods: The formulations were prepared by the Quasi-emulsion solvent diffusion method and characterized for particle size and drug entrapment efficiency. For the optimization of the formulation through the Quality by Design (QbD) approach, Quality target product profiles (QTPP) were set up considering various key factors that affect the quality of the formulation. Further optimization of the important factors in relation to the major Critical Quality Attributes (CQAs) was conducted by applying full factorial design using the Design of Expert Software (11.0 software, Stat-Ease, Inc., USA). The optimized formulation was incorporated into the gel, and characterized for morphological analysis by Scanning Electron Microscopy (SEM), drug content, and ex-vivo permeation studies (DD solver, Version 2.0). Results: It was found that process parameters such as drug-to-polymer ratio, the volume of the internal phase, and concentration of the emulsifier and polyvinyl alcohol (PVA), played a crucial role in improving the drug entrapment efficiency and particle size. On the other hand, stirring time did not significantly affect the particle size. Through Design of Expert (DOE) analysis, a PVA concentration of 0.641 mg/ml and an internal phase volume of 12.5 ml were identified to be the ideal concentrations to obtain the optimized microspongal gel formulation (MS4). Characterization studies were carried out on MS4, which displayed a drug encapsulation of 94%, with a Cmax of 81.62 mg/ml, and a Tmax of 12 h. Stability studies carried out as per the International Conference of Harmonization (ICH) guidelines confirmed no noticeable change in physical appearance and drug content. Conclusion: Overall, this study focused on optimizing the formulation of microsponges for efficient dermal drug delivery, considering various critical variables and process parameters. The resulting optimized formulation demonstrated promising drug release and potential for the effective management of inflammation disorders.

Study the Variables Affecting Formulation of Ethylcellulose-based Microsponges Loaded with Clobetasol

Clobetasol propionate (CP) is a super potent corticosteroid widely used to treat various skin disorders such as atopic dermatitis and psoriasis. However, its utility for topical application is hampered due to its common side effects, such as skin atrophy, steroidal acne, hypopigmentation, and allergic contact dermatitis. Microsponge is a unique three-dimensional microstructure particle with micro and nano-meters-wide cavities, which can encapsulate both hydrophilic and lipophilic drugs providing increased efficacy and safety. The aim of the current study is to prepare and optimize clobetasol-loaded microsponges. The emulsion solvent diffusion method is used for the preparation of ethylcellulose (EC)-based microsponges. The impact of various formulation variables on microsponge's properties includes; drug: polymer ratio, polyvinyl alcohol (PVA) quantities, the volume of external phase, and stirring rates investigated. The microsponges were characterized in terms of particle size, product yield, CP entrapment %, and in-vitro drug release behavior. The results report that increasing EC concentration led to a significant increase in particle size, with a decrease in product yield and drug entrapment %. Increasing stirring speed or external aqueous volume or PVA w/v % caused a non-significant decrease in production yield and CP entrapment % but showed a significant decrease, and increase in particle size, respectively. Finally, it was concluded that the ability to use ethylcellous as a Msg polymer matrix to prepare uniform, highly porous particles was confirmed by microscope observation and compatibility with CP.

Fiber spinning from polymer solutions

The thinning of a cylinder of a polymer solution in a volatile solvent is argued to be controlled by solvent diffusion through a dense polymer layer at the cylinder surface. This naturally leads to the exponential time dependence of cylinder radius that is observed in experiments using a fast camera, such as capillary breakup extensional rheometry (CaBER). The relaxation time is controlled by the thickness of the dense (and often glassy) polymer layer and the diffusion coefficient of solvent through that layer. If correct, this means that while CaBER is very useful for understanding fiber spinning, the relaxation time does not yield a measure of the extensional viscosity of polymer solutions in volatile solvents.

Frontiers of NIR Imaging

After a brief introduction to the technique, this review will discuss the state-of-the-art NIR imaging instrumentation and its applications, including applications of an ordinary NIR imaging system to solvent diffusion into a polymer. Other imaging applications discussed include the use of a portable NIR imaging system in the pharmaceutical industry, high-speed and wide-area monitoring of polymers, and imaging for fish embryos development research. Also discussed is an imaging-type two-dimensional Fourier spectroscopy (ITFS) system and its application to medaka (Japanese rice fish, Oryzias latipes) egg development. Finally, general perspectives on NIR imaging will be provided.