Hyperuniformity of Maximally Random Jammed Packings of Hyperspheres Across Spatial Dimensions

The maximally random jammed (MRJ) state is the most random configuration of strictly jammed (mechanically rigid) nonoverlapping objects. MRJ packings are hyperuniform, meaning their long-wavelength density fluctuations are anomalously suppressed compared to typical disordered systems, i.e., their structure factors $S(\mathbf{k})$ tend to zero as the wavenumber $|\mathbf{k}|$ tends to zero. Here, we show that generating high-quality strictly jammed states for space dimensions $d = 3,4,$ and $5$ is of paramount importance in ensuring hyperuniformity and extracting precise values of the hyperuniformity exponent $\alpha > 0$ for MRJ states, defined by the power-law behavior of $S(\mathbf{k})\sim|\mathbf{k}|^{\alpha}$ in the limit $|\mathbf{k}|\rightarrow0$. Moreover, we show that for fixed $d$ it is more difficult to ensure jamming as the particle number $N$ increases, which results in packings that are nonhyperuniform. Free-volume theory arguments suggest that the ideal MRJ state does not contain rattlers, which act as defects in numerically generated packings. As $d$ increases, we find that the fraction of rattlers decreases substantially. Our analysis of the largest truly jammed packings suggests that the ideal MRJ packings for all dimensions $d\geq3$ are hyperuniform with $\alpha = d - 2$, implying the packings become more hyperuniform as $d$ increases. The differences in $\alpha$ between MRJ packings and recently proposed Manna-class random close packed (RCP) states, which were reported to have $\alpha = 0.25$ in $d=3$ and be nonhyperuniform ($\alpha = 0$) for $d = 4$ and $d = 5$, demonstrate the vivid distinctions between the large-scale structure of RCP and MRJ states in these dimensions. Our work clarifies the importance of the link between true jamming and hyperuniformity and motivates the development of an algorithm to produce rattler-free three-dimensional MRJ packings.Comment: 15 pages, 8 figure

INTRANASAL MICROEMULGEL AS SURROGATE CARRIER TO ENHANCE LOW ORAL BIOAVAILABILITY OF SULPIRIDE

Objective: The purpose of this study is to evaluate microemulsion based gel (MBG) of sulpiride "a poorly water soluble antipsychotic with low oral bioavailability."Methods: Gelling polymers such as sodium carboxymethylcellulose (CMC-Na), hydroxyl propyl methyl cellulose (HPMC K4m), carbopol 940 and Na alginate were evaluated for their potential to gel sulpiride microemulsions (MEs) without affecting the MEs structure. Also, sulpiride solution (SS) and conventional gel (without ME) were prepared and compared with MBG. Gel formulations were checked for their viscosity, pH, spreadability (S), mucoadhesive force (MF), and nasal ciliotoxicity studies. The in vitro release of sulpiride across a cellophane membrane and its permeation through the nasal mucosa in phosphate buffered saline pH 6.8 (PBS) were also performed. In addition, a pharmacodynamic study of optimized formulae compared to SS and microemulsion (ME) was evaluated in rats.Results: CMC-Na and HPMC K4m were not able to gel sulpiride loaded MEs while Na alginate gave an unclear gel with a sticky texture. Results revealed that the viscosity, mucoadhesion force, and spreadability of the MBG increased with increasing carbopol 940 concentrations. The flux was arranged as the following, MBG>conventional gel>sulpiride solution (SS). According to histopathological study, safe and non-irritant MBGs suitable for nasal administration were successfully prepared. Finally, the pharmacodynamic study indicated that intranasal sulpiride MBG had a significant effect (*P<0.001) than SS and ME administered either intravenous or intranasal.Conclusion: MBG provides signiï¬cant enhancement in nasal bioavailability not only by absorption enhancing effect of ME but also, by increasing nasal residence tim

Impact of powder recoating speed on built properties in PBF-LB process

In powder bed fusion laser-beam (PBF-LB), powder deposition parameters are not commonly adjusted for different materials. In this study, the recoater speed was varied from 150 mm/s to 500 mm/s to study its influence on processability of two different powders. The 420 steel powder possesses better flowability and higher packing density than Inconel 718 at different testing speeds. This is reflected on surface roughness (Sa): Inconel 718 samples show larger variations than 420 steel ones across different locations on the build plate and under different recoating speeds. This demonstrates the necessity of accounting for powder properties for robust PBF-LB processing

FORMULATION DEVELOPMENT AND EVALUATION OF NIOSOMAL GEL OF COLLECTIVE ANTI-FUNGAL AGENTS

Objectives: Tea tree oil (TTO) and Eucalyptus oil (EO) are essential oils derived from the leaves and terminal branches of Melaleuca alternifolia and Eucalyptus globulus. Both oils have narrative topical antifungal agents. Niosomal vesicles were chosen for Tea tree and EO dispersion in this investigation because of their ability to protect enclosed drugs, reduce drug dose amount, target drug delivery, increase residence time and penetration. Methods: TTO and EO containing niosomes were made using a modified thin-film hydration process and Carbopol 934 as a gelling agent to produce a smooth antifungal niosomal gel. Results: TTO and EO entrapment efficiency was found to be 84.89±0.19% and 86.86±0.57%, respectively, and percent cumulative drug diffusion of TTO and EO was found to be 84.21% and 85.22% in the prepared optimized batch [N9]. Transmission electron microscopy revealed vesicular, spherical particles in the nano range with a smooth surface. The optimum batch [N9] of niosomal gel was made with 1% w/w carbopol 934. TTO 84.9% and EO 86.89%, respectively, were found to have prolonged drug release in an in vitro release investigation utilizing the dialysis bag method. The G9 batch niosomal gel was found to be stable by performing an accelerated stability study for 3 months. Conclusion: It was concluded that the best formulation batch G9 shows better-sustained release, enhanced residence time, and stability

Influence of plasma on the physical properties of the ointments with quercetin

Effects of two independent variables – the content of quercetin (0 or 1 or 1.5 or 5 %) and the content of plasma (0 or 2 or 4 or 6 %) – on the organoleptic properties and rheological parameters of model formulations prepared on an amphiphilic base were estimated. The consistency of all ointments was uniform, and the content of quercetin and plasma lay within the predefined range. Tested ointments are non-Newtonian systems. The content of quercetin and plasma was found to have a significant effect on the rheological properties of the ointments. An increase in the content of plasma in ointments was accompanied by a significant increase in their hardness, viscosity and shear stress and a reduction of their spreadability. The best rheological properties were shown by formulation F-3, containing 1.5 % of quercetin and 2 % of plasma

FORMULATION OF KETOCONAZOLE LOADED NANO DISPERSIVE GEL USING SWOLLEN MICELLES TECHNIQUE AND ITS IN VITRO CHARACTERIZATION

Objective: The objective of the present work was to formulate and characterize nano dispersive gel (NDG) for topical delivery of water-insoluble antifungal agent ketoconazole in order to enhance its solubility, penetration through the skin and antifungal activity.Methods: Nano dispersion of the drug was first prepared by swollen micelles technique (SMT) using tween 80 and chloroform which is then incorporated into the gel using carbopol 934. Ten formulations of ketoconazole loaded NDG was prepared and characterized for different physicochemical parameters like homogeneity, pH, spreadability, extrudability, practical yield, drug content, in vitro drug release, ex vivo permeation study, and biological parameter antifungal activity.Results: The formulated topical preparation exhibit pH in the range of 6.5 to 7.4, and unveiled excellent homogeneity, spreadability and extrudability. Out of 10 formulations, formulation F4 showed maximum drug content of 95.56±1.13% and practical yield of 97.23±0.51%. The in vitro drug release studies were performed using pH 7.4 phosphate buffer. Formulation F4 showed best in vitro drug release 96.52±0.52% at the end of 24 h of study. Ex vivo permeation study of formulation F4 carried out using franz diffusion cell, also manifested good permeation and flux of drug across the chicken skin. Antifungal activity test of formulation F4 was carried out by the cup plate method using Aspergillus niger strain against marketed ketoconazole unveiled higher antifungal activity than marketed one.Conclusion: The study confirmed formulation F4 to be an optimized and promising formulation for the effective treatment of topical fungal infections with enhanced solubility and penetration through the skin

Formulation and Evaluation of Transdermal Topical Gel of Ibuprofen

The present research work is based on the formulation and evaluation of topical gel of Ibuprofen where Carbopol 940 is used as the polymer. Gels were prepared by dispersing the polymers  in a mixture of water and glycerol with methyl paraben as the preservative and the varying amount of ibuprofen, being kept under magnetic stirring until the homogeneous dispersion was formed. The dispersion was then neutralized and made viscous by the addition of triethanolamine. The Carbopol gels of Ibuprofen were found to be homogenous with good drug loading. The pH of all the gel formulations was found within the neutral pH range which is compatible with skin. And the viscosity of the formulations was found to be feasible for topical drug delivery. The drug content of the three formulations was found in the range of 87.56% to 90.45% which shows efficient drug loading. Results of In vitro drug release study showed that F5 formulation has better diffusion of drug through egg membrane and hence further permeation studies were carried out through rat epidermis. The compatibility study showed that the major peaks in FTIR spectra of the pure drug were found to be intact in their physical mixture. Hence there is no interaction between drug and Carbopol in their physical mixture. Carbopol can be effectively used as the polymer for topical gel preparation. And F5 formulation containing 0.5 % w/w Carbopol 940 may be effectively used as topical transdermal delivery for Ibuprofen. Keywords: Ibuprofen, Transdermal Gel, Drug release, Compatibility stud

FORMULATION AND IN VITRO CHARACTERISATION OF SOYBEAN OIL-HPMCK4M BASED BIGEL MATRIX FOR TOPICAL DRUG DELIVERY

Objective: Hydrogels with scope for utilization in numerous fields possess limited applications due to problems in incorporating wide range of drugs and crossing the lipophilic barrier of the skin. Attempts to overcome these problems by developing organogel hold drawbacks. Challenges posed by drug lipophilicity or skin permeation can be solved by developing bigel formed via combination of lipophilic and hydrophilic gel phases in a definite proportion. The objective of the present study is to formulate and characterize matrix type bigel of soybean oil and HPMCK4M for topical drug delivery. Methods: Four batches of bigels were developed with two organogel formulations of soybean oil containing 20 and 22% w/v Span 60. Both organogels and bigels were examined for compatibility by FTIR spectroscopy, hemocompatibility and characterized for physical appearance, pH, rheological behavior and in vitro drug release pattern. Results: FTIR study confirmed compatibility between paracetamol and components of organogel or bigel. The oily feel of organogels disappeared with bigels which possessed a creamy and smooth texture. Pseudoplastic behaviour was confirmed by Ostwald-de wale power-law model in both organogels and bigels. Improved drug release was observed in bigel (BG1) formulation containing 3%w/v HPMCK4M and soybean oil based organogel with 20% w/v Span 60 as compared to the corresponding organogel (OG1). Organogels were foundto follow either zero-order kinetics (OG1) or Korsmeyer-Peppasmodel (OG2) while the formation of matrix was exhibited in bigels with drug diffusion predominantly of non-Fickian type. Conclusion: Therefore, bigels of soybean oil based organogel with HPMCK4M hydrogel formed gel matrix demonstrating improved drug release for topical application compared to organogel

Selection of the conveyor belt material for edible film production by a continuous casting process

The scaling up of the wet process and the design of a coating line to produce edible films, require the consideration of several factors such as, the film formulation, drying kinetics of the films, and the selection of a suitable support material in which to pour the solution. This work aimed to select the most suitable material for the construction of a conveyor belt for the fabrication of edible films through the wet process. The surface properties of the starch film-forming solution were determined. Several commercial materials for conveyor belts were tested. The film-forming solution spreadability and work of adhesion were determined. The mechanical behavior of the dry film was evaluated through mechanical properties and peeling resistance. All materials tested showed good performance under the operational conditions assayed to obtain edible films. Finally, the polyurethane band was chosen due to its appropriate performance and lower cost.O escalonamento do processo a úmido e o design de uma linha de revestimento para a produção de filmes comestíveis exigem a consideração de vários fatores, como a formulação do filme, a cinética de secagem dos filmes e a seleção de um material de suporte adequado no qual será despejada a solução. O objetivo deste trabalho foi selecionar o material mais adequado para a esteira transportadora, a fim de construir equipamentos para a fabricação de filmes comestíveis através do processo a úmido. As propriedades da superfície da solução filmogênica de amido foram determinadas. Vários materiais comerciais para esteira transportadora foram testados. A dispersibilidade da solução filmogênica e o trabalho de adesão foram determinados. O comportamento mecânico do filme seco foi avaliado por meio das propriedades mecânicas e da resistência ao destacamento. Todos os materiais testados apresentaram bom desempenho nas condições operacionais testadas para obtenção de filmes comestíveis. Finalmente, a esteira de poliuretano foi escolhida devido ao seu desempenho adequado e menor custo.Fil: Gamboni, Jimena Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; ArgentinaFil: Colodro, María Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; ArgentinaFil: Slavutsky, Anibal Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; ArgentinaFil: Bertuzzi, Maria Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentin

ANTIMICROBIAL POTENTIAL OF HYDROGEL INCORPORATED WITH PLGA NANOPARTICLES OF CROSSANDRA INFUNDIBULIFORMIS

Objective: Present study is aimed at formulation of Hydrogel containing Poly Lactic Glycolic Acid (PLGA) nanoparticles incorporated with ethanolic extract of Crossandra infundibuliformis (EECI) and investigate the efficacy of hydrogel nanoparticles as a carrier of antimicrobial constituents. Methods: Poly Lactic Glycolic Acid (PLGA) nanoparticles containing ethanolic extract of Crossandra infundibuliformis (EECI) were synthesized by an emulsion-evaporation method and their physicochemical properties were studied. Polymeric PLGA nanoparticles were then incorporated into gel matrix, using Hydroxy Propyl Methyl Cellulose (HPMC K4M) as a base. The antibacterial activity of nanoparticulated hydrogel formulations were evaluated by agar well diffusion method against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. Results: Nanoparticulate hydrogel formulations exhibited high viscosity, neutral pH with good spreadability which is appropriate for transdermal application as well as showed prolonged drug release from optimized formulation up to 24 h. Nanoparticulate hydrogel formulations were effective inhibitors of all the micro-organisms with more promising activity against Staphylococcus aureus. Conclusion: Nanoparticulate hydrogel formulation can be used as a feasible alternative to conventional formulations of Crossandra infundibuliformis extract with advanced permeation characteristics of antimicrobial constituents for transdermal application