Central Composite Experimental Design Research Articles

Production of N–Mg doped biochars for phosphate adsorption from renewable sources

It is crucial for the environment, the economy, and society to create low-cost adsorbents from renewable resources to remove phosphate from aqueous effluents. Here, two renewablecarbon and nitrogen sources (Douglas fir and Chitosan) were used to produce engineered N-doped biochars modified with Mg for PO43− adsorption. Mg–N doped biochars were prepared using an impregnation-carbonization process. A central composite experimental design was used to select combinations of independent variables to maximize phosphate adsorption capacity. Phosphate adsorption isotherms were fitted with Langmuir and Freundlich isotherms. The biochar produced at 700 °C, 12 wt % MgCl2, and Douglas Fir/Chitosan ratio: 1/1, which has the highest PO43− adsorption capacity, was further studied. Proximate analysis, elemental composition, surface area, pore size distribution, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and Scanning electron microscopy combined with energy-dispersive X-ray spectroscopy (SEM-EDX) were used to characterize this biochar. This biochar has an adsorption capacity of 112.4 mg PO43−/g char. Its phosphate adsorption rate was adjusted to a pseudo-second-order kinetic model. The phosphate adsorption capacity of the biochar produced was comparable with the most effective biochar reported in the literature.

Optimization of the FDM Processing Parameters on the Compressive Properties of ABS Objects for the Production of High-Heeled Shoes

The influence of 3D printing parameters on compressive properties is an important factor in the application of additive manufacturing processes for products subjected to compressive loads in use. In this study, the compressive strength and compressive modulus of acrylonitrile/butadiene/styrene (ABS) test specimens fabricated using the fused deposition modeling (FDM) process were investigated with the aim of producing products of high-heeled shoes for women. The experimental part of the study includes a central composite experimental design to optimize the main 3D printing parameters (layer thickness, infill density, and extrusion temperature) and the infill geometry (honeycomb and linear at a 45° angle—L45) to achieve maximum printing properties of the 3D-printed products. The results show that the infill density has the greatest influence on the printing properties, followed by the layer thickness and, finally, the extrusion temperature as the least influential factor. The linear infill at a 45° angle resulted in higher compressive strength and lower compressive modulus values compared to the honeycomb infill. By optimizing the results, the maximum compressive strength (that of L45 is 41 N/mm2 and that of honeycomb 35 N/mm2) and modulus (that of L45 is 918 N/mm2 and that of honeycomb is 868 N/mm2) for both types of infill is obtained at a layer thickness of 0.1 mm and infill density of 40%, while the temperature for L45 can be in the range of 209 °C to 254 °C, but for the honeycomb infill, the processing temperature is 255 °C. Additionally, the study highlights the potential for sustainable manufacturing practices and the integration of advanced 3D printing technologies to enhance the efficiency and eco-friendliness of the production process.

Characterization and optimization of ultrasound assisted oxidative desulfurization of a model fuel using a novel magnetic deep eutectic solvent

ABSTRACT In various studies, researchers have utilised different solvents to extract sulfur compounds from the fuels. This paper introduces a novel magnetic deep eutectic solvent employed in the ultrasound-assisted oxidative desulfurisation of dibenzothiophene within a model fuel. The solvent, synthesised at 85°C by combining choline chloride, p-toluene sulfonic acid, and FeCl₃, underwent characterisation through Fourier transform-infrared, Vibrating-sample magnetometer, and Raman spectrometry. Exploration of the key parameters, including oxidant to model fuel volumetric fraction percentage (0.2–0.3), Iron (III) chloride to choline chloride mole fraction (0.1–0.3), and Magnetic deep eutectic solvent to model fuel volumetric fraction (0.2–0.3), was conducted to assess their impact on dibenzothiophene conversion rates. Employing response surface methodology based on central composite experimental design, optimal operational parameters for the ultrasound-assisted oxidative desulfurisation process were identified, resulting in a sulfur removal rate of 98.7%. The findings highlight the solvent sustained efficiency even at higher dibenzothiophene concentrations. Additionally, the solvent paramagnetic properties facilitated an expedited separation from the fuel, leading to the significantly reduced process times.

REINFORCEMENT OF COMPRESSED STABILIZED EARTH BLOCKS WITH BIOCHAR RESULTING FROM USE OF AGRO-INDUSTRIAL WASTE

ABSTRACT Over the past few decades, the transformation and utilization of materials obtained from agricultural residues as a circular economy strategy have been extensively discussed. Rice husk has received special attention due to the presence of biogenic oxides or biosilica (Gomez-Vazquez et al., 2022; Shafigh et al., 2014; A. B. Souza et al., 2021). This study aimed to evaluate the technical feasibility of using rice husk biochar, a by-product of bioenergy utilization of this agroindustry waste, by developing a multi-factor statistical analysis during the formulation of compressed stabilized earth blocks (CSEB). A central composite experimental design was implemented to examine the contribution of factors such as the percentage of biochar (2.5–17%) and drying temperature (40–100°C) of the CSEB on its mechanical properties. The ANOVA analysis and response surface evaluation demonstrated that biochar up to 14.5% could be added while maintaining a minimum strength of 2MPa. Moreover, the drying temperature significantly affected the mechanical strength of the CSEB, and a complex interaction between clay and biochar was observed, allowing for high mechanical strength and adsorption capacities of the CSEB simultaneously.

Salt slag and rice husk ash as raw materials in zeolite synthesis: Process optimization using central composite rotational design

The growing demand of zeolites for many industrial applications has led to a search for eco-friendly alternatives for their production, in an attempt to reduce costs, save natural resources and alleviate the associated environmental impacts. In the present study, hazardous aluminum salt slag (aluminum source) and rice husk ash (silicon source) were used as secondary raw materials to synthesize sustainable NaP-type zeolites through a hydrothermal process. A central composite rotational experimental design was applied to evaluate the effect of the reaction time and hydrothermal temperature on the obtained zeolites crystallinity. Using the proposed experimental design, temperatures between 85 and 115 °C and different reaction times (2–28 h) were tested. It was found that the interaction between the variables (time and temperature) and both variables, independently, exerted a significant influence on the crystallinity of the zeolites. The optimal experimental conditions (105 °C and 20 h), statistically determined, enabled a high degree of crystallinity (>73%) to be achieved. Thus, the use of hazardous aluminum and agri-food wastes as unconventional precursors for the production of zeolites represents a sustainable alternative to manage these wastes, by transforming them into secondary raw materials.

N‐Butane Isomerization over 0.5 Pt/HPA/MCM‐41 Catalyst: Optimization Study Using Central Composite Design

AbstractIn this research, 0.5 % platinum (Pt)/HPAs/MCM‐41 (Mobil Composition of Matter No. 41) bifunctional catalysts (with different weight percentages of phosphotungstic acid (HPW) and silicotungstic acid (HSiW)) were synthesized for use in the n‐butane isomerization. The synthesized catalysts were characterized by X‐ray diffraction, X‐ray fluorescence spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, Brunauer–Emmett–Teller, and ammonia temperature‐programmed desorption analyses. The best catalytic activity and highest initial isobutane yield at 250 °C, weight hourly space velocity of 0.15 h−1, and H2/nC4 molar ratio of 3:1 belonged to 0.5 %Pt/20 % HPW/MCM‐41 (41 %) and 0.5 % Pt/40 % HSiW/MCM‐41 (45 %) samples. Subsequently, the yield of isobutane over these catalysts was evaluated and optimized by a central composite experimental design. According to the quadratic model, the maximum isobutane yield under optimal operating conditions was 34.5 % and 41.36 %, respectively, for 0.5 % Pt/20 % HPW/MCM‐41 and 0.5 % Pt/40 % HSiW/MCM‐41 catalysts.

On the optimized fused filament fabrication of polylactic acid using multiresponse central composite design and desirability function algorithm

Efficient optimization of polymeric materials in fused filament fabrication 3D printing (FFF 3DP) is crucial for productivity, cost reduction, resource conservation, consistency, and enhanced part performance. This study employed a multiresponse central composite design of experiments (CCD-DOE) with the desirability function algorithm (DFA) to optimize printing settings on polylactic acid (PLA) using a commercial FFF 3D printer. The goal was to identify optimal parameters for faster build time and reduced material usage in PLA part fabrication. The fabrication process involved computer-aided design and modeling of standard PLA dogbone specimens, meeting ASTM-D638 Type 1 tensile test standards. These specimens were then 3D printed using Ultimaker Green RAL 6018 PLA filament and a 2+ model printer set at varying print parameters. Reduced second-order polynomial models for printing time and PLA weight were generated using stepwise regression, eliminating noninfluential parameters. The models revealed that higher layer thickness, increased print speed, and lower infill density resulted in faster printing times, while lower infill density and higher layer thickness led to lighter PLA prints. DFA analysis determined the optimal settings as a layer thickness of 0.26–0.30 mm and an infill density of 35% for minimizing printing time and PLA weight. The stress–strain curves displayed characteristic high-strength, brittle behavior under tension, while tensile testing of optimized PLA parts revealed increased strength with low strain at the break when layers were aligned parallel to the applied force. These findings advance additive manufacturing and provide practical guidelines for high-quality 3D-printed PLA components. Optimizing FFF 3DP parameters enables efficient production with reduced time and material usage, enhancing cost-effectiveness and the fabrication of high-performance 3D printed products.

Оптимизация параметров импульсной лазерной наплавки стали 30ХГСН2А с использованием генетического алгоритма

The paperpresents the optimization of pulsed laser cladding of structural steel using a genetic algo-rithm. Using the ANSYS Workbench software, finite element modelling of laser cladding on a 30ХГСН2А steel substrate with an additive in the form of wire was conducted, considering the temperature dependence of the material's thermophysical properties. A surrogate model for pulsed laser cladding of 30ХГСН2Аsteel was developed employing a face-centered version of the central composite design experiment. The time inter-vals corresponding to the end time of the three fronts of the laser pulse and the diameter of the filler wire were considered as variable factors. The maximum temperatures in the treatment zone were used as re-sponses. In order to optimize pulsed laser cladding of 30ХГСН2А steel, the maximum temperature limit val-ues in the treatment zone were established for three moments of time that corresponded to the laser pulse fronts at the three points in the finite element model. A comparison was made between the parameters ob-tained from optimization and those derived from finite element modelling. When determining temperatures, the maximum percentage error of the results obtained via the genetic algorithm did not exceed 3.5 %

Preparation of Compound Salvia miltiorrhiza-Blumea balsamifera Nanoemulsion Gel and Its Effect on Hypertrophic Scars in the Rabbit Ear Model.

Hypertrophic scars (HS) still remain an urgent challenge in the medical community. Traditional Chinese medicine (TCM) has unique advantages in the treatment of HS. However, due to the natural barrier of the skin, it is difficult for the natural active components of TCM to more effectively penetrate the skin and exert therapeutic effects. Therefore, the development of an efficient drug delivery system to facilitate enhanced transdermal absorption of TCM becomes imperative for its clinical application. In this study, we designed a compound Salvia miltiorrhiza-Blumea balsamifera nanoemulsion gel (CSB-NEG) and investigated its therapeutic effects on rabbit HS models. The prescription of CSB-NEG was optimized by single-factor, pseudoternary phase diagram, and central composite design experiments. The results showed that the average particle size and PDI of the optimized CSB-NE were 46.0 ± 0.2 nm and 0.222 ± 0.004, respectively, and the encapsulation efficiency of total phenolic acid was 93.37 ± 2.56%. CSB-NEG demonstrated excellent stability and skin permeation in vitro and displayed a significantly enhanced ability to inhibit scar formation compared to the CSB physical mixture in vivo. After 3 weeks of CSB-NEG treatment, the scar appeared to be flat, pink, and flexible. Furthermore, this treatment also resulted in a decrease in the levels of the collagen I/III ratio and TGF-β1 and Smad2 proteins while simultaneously promoting the growth and remodeling of microvessels. These findings suggest that CSB-NEG has the potential to effectively address the barrier properties of the skin and provide therapeutic benefits for HS, offering a new perspective for the prevention and treatment of HS.

Improved L-Asparaginase Properties and Reusability by Immobilization onto Functionalized Carbon Xerogels.

Enzyme immobilization can offer a range of significant advantages, including reusability, and increased selectivity, stability, and activity. In this work, a central composite design (CCD) of experiments and response surface methodology (RSM) were used to study, for the first time, the L-asparaginase (ASNase) immobilization onto functionalized carbon xerogels (CXs). The best results were achieved using CXs obtained by hydrothermal oxidation with nitric acid and subsequent heat treatment in a nitrogen flow at 600 °C (CX-OX-600). Under the optimal conditions (81 min of contact time, pH 6.2 and 0.36 g/L of ASNase), an immobilization yield (IY) of 100 % and relative recovered activity (RRA) of 103 % were achieved. The kinetic parameters obtained also indicate a 1.25-fold increase in the affinity of ASNase towards the substrate after immobilization. Moreover, the immobilized enzyme retained 97 % of its initial activity after 6 consecutive reaction cycles. All these outcomes confirm the promising properties of functionalized CXs as support for ASNase, bringing new insights into the development of an efficient and stable immobilization platform for use in the pharmaceutical industry, food industry, and biosensors.

Investigation on Surface Integrity in Milling of Inconel X750: A Comprehensive analysis of Cutting Edges and Machining Parameters

For over a century, machining has been a crucial manufacturing method, with milling standing out as a versatile and effective process for various engineering materials. Ni-based superalloys, renowned for their exceptional properties, present challenges in machining, causing excessive tool wear and surface quality issues. Techniques such as heat treatments, environmental adjustments, and tool geometry alterations are employed to mitigate tool wear and affect surface integrity, crucial for determining the quality of machined work materials, especially in high-strength superalloys where shear deformation induces grain misorientation. In this research article, an experimental study was carried out to find the impact of the different cutting edges on surface integrity while milling Inconel X750. Response Surface Methodology was employed using a central composite rotatable design of experiments to investigate the surface roughness of the machined sample under various cutting conditions. A thorough analysis was undertaken to explore the surface integrity of Inconel X750, involving variations in milling machining parameters (i.e., low, mid, and high) and the utilization of diverse cutting tool inserts. The investigation centred on analysing the sub-surface microstructure, texture, and residual stresses of the machined surface, aiming to achieve a comprehensive understanding of the material's surface characteristics. The double-coated cutting tool T2, with a diameter of 0.8 mm, exhibited superior performance in surface quality and grain distribution, particularly at low cutting parameters (feed rate: 0.15 mm/rev, cutting speed: 35 mm/min, depth of cut: 0.1 mm), showing fine equiaxed and lognormal grain distribution alongside low residual stresses (−36.8 MPa compressive, maximum shear residual stresses: 7.2 MPa) and a surface roughness of 0.17 μm.

A Combined Paddy Field Inter-Row Weeding Wheel Based on Display Dynamics Simulation Increasing Weed Mortality

Weeds compete with rice for sunlight and nutrients and are prone to harboring pathogens, leading to reduced rice yields. Addressing the issues of low weeding efficiency and weed mortality rates in existing inter-row weeding devices, the study proposes the design of a combination paddy field inter-row weeding wheel. The device’s operation process is theoretically analyzed based on the weed control requirements in the northeastern region of China, leading to the determination of specific structural parameters. This research conducted experiments on the mechanical properties of weed cutting to obtain geometric parameters for paddy field weeds. It was found that the range for the cutting gap of the dynamic–fixed blade is between 0.6 mm to 1.4 mm and the cutting angle is between 5° to 15°, resulting in the lowest peak cutting force for weeds. Using LS-DYNA R12.0.0 dynamic simulation software, a fluid–structure interaction (FSI) model of the weeding wheel–water–soil system was established. By employing the central composite experimental design principle and considering the soil stir rate and coupling stress as indicators, the optimal structural parameter combination for the device is obtained: a dynamic–fixed blade cutting gap of 1.4 mm, a cutting angle of 10.95°, and a dynamic blade install angle of −3.44°. Field experiments demonstrated that the device achieved an average weeding rate of 89.7% and an average seedling damage rate of 1.9%, indicating excellent performance. This study contributes to improving weed mortality rates and provides valuable guidance for inter-row mechanical weeding technology.

Combined hydroxyphenyl-modified adhesive with the ion-pair strategy for long-lasting delivery of clonidine in single-layer matrix-type patch

Existing long-acting patches usually use controlled-release membranes to achieve constant rate delivery of the drug, which is complex and costly to prepare due to the 5-layer structure, so there is a necessity to develop a method to simplify the patch design and to control constant rate drug delivery. This study prepared a 7-day long-acting clonidine (CLO) patch using the ion-pair strategy based on hydroxyphenyl-modified pressure-sensitive adhesive (HP-PSA) and clarified the molecular mechanism of controlled delivery. Single factorial and central composite design (CCD) experiments were used to optimize the patch formulation, which was evaluated by a pharmacokinetic study. The controlled drug delivery mechanism was investigated by FTIR, 1H NMR, differential scanning calorimetry (DSC), confocal laser scanning microscopy (CLSM), molecular modeling, and rheology study. The optimized patch was formulated with 4.80% (w/w) CLO-AA (azelaic acid) as API and HP-PSA as PSA matrix and 95.00 μm thickness. The single-layer patch not only simplifies the preparation process but also has a zero-level skin penetration profile (r = 0.9592) in vitro. Compared with the commercial patch (AUC0-t = 7748.51 ± 662.76 h ng/ml, MRT0-t = 71.04 ± 9.30h), the pharmacokinetic behavior of the optimization group was semblable (AUC0-t = 8160.28 ± 694.04 h ng/ml, MRT0-t = 63.19 ± 12.38h). Mechanistic studies showed that ion-pair improved drug interaction with HP-PSA, leading to controlled drug release. Changes in drug physicochemical properties decreased skin permeability and increased drug-skin interaction, resulting in a constant delivery rate. In conclusion, the 7-day long-acting drug delivery of the CLO patch was achieved by the ion-pair strategy, which simplified the preparation process, and inspired a long-acting transdermal drug delivery system.

Utilizing discarded face masks to fabricate sustainable high-performance panels for enhanced building thermal and acoustic comfort

This study aims to design, fabricate, and optimize fibrous panels made of discarded polypropylene face masks (FMs) for application in sound absorption and thermal insulation. The discarded FMs were shredded and transformed into a fibrous mass using a Garnet machine. The resulting fibers, after being mixed with a bio-based binder, were molded based on an experimental design using response surface methodology in conjunction with the central composite experiment design (RSM-CCD) with five different thicknesses, densities, and blending ratios of spunbond to meltblown fabrics. The average of the sound absorption coefficients for the twelve one‐third‐octave bands from 200 to 2500 Hz (SAA) and effective thermal conductivity (Keff) of the panels were measured as the dependent parameters. These values were calculated within the ranges of 0.28–0.53 and 0.031–0.056 W/(mK), respectively. Additionally, the interactive effects of input variables on SAA and Keff of the manufactured panels were discussed. The quadratic and two-factor interaction models were proposed for optimizing the values of SAA and Keff, respectively. The optimal conditions were determined to achieve the maximum SAA and minimum Keff in a thickness of 26.7 mm, density of 135 kg/m3, and blending percentage of 32.4 %. Under these conditions, the measured values of SAA and Keff were 0.534 and 0.0279 W/mK, respectively. Finally, three fibrous panels were manufactured under optimal conditions, and their acoustic and thermal properties were measured. It was observed that excellent agreement exists between the model results and the experimental data with a 95% confidence level. The bending properties of the optimally designed panels were also investigated and the panels exhibited an impressive flexural strength of 2.1 MPa. Additionally, the fire performance of the panels was examined and all panels showed self-extinguishing properties. These findings suggest that panels made of discarded FMs hold promise as an eco-friendly and sustainable construction material for manufacturing acoustic and thermal insulation panels. Moreover, the frequency-dependent absorption coefficients of the panels were predicted using the Johnson-Champoux-Allard model.

Tailoring Nitrogen‐Doped Activated Carbons: Central Composite Design for Enhanced CO2 Adsorption

AbstractIn a single step, nitrogen‐doped activated carbons have been synthesized using walnut shells and urea as precursors by chemical activation with K2CO3. The textural and elemental properties such as surface area, micropore volume, nitrogen content, and yield were optimized in a multivariable way using a central composite design of experiments 23, varying the urea‐nutshell ratio, K2CO3 ratio, and activation temperature. Activated carbon doped with the highest nitrogen presented a surface area of 895 m2 g−1, a micropore volume of 0.22 cm3 g−1, and a nitrogen content of 4.11 %. Furthermore, the yield of 13.85 % at urea impregnation ratio 1.56 gUrea gNutshell−1, activating agent ratio 1.4 gK2CO3 gCarbon−1, and temperature of 591 °C, being the temperature and the urea impregnation ratio the significant variables in the responses evaluated. The best‐activated carbon doped with nitrogen presented a CO2 adsorption capacity of 2.78 mol kg−1, reversible adsorption‐desorption, and selectivity against nitrogen of 33.2 molCO2/molN2, superior to a commercial activated carbon with similar textural properties at the same experimental conditions and being in the order of magnitude as activated carbons synthesized under similar conditions.

Sustainable appraisal of lipstick tree seeds (Bixa orellana)-based bixin natural orange colorant for green mordanted silk fabrics and wool yarns.

This research aims to optimize the silk and wool dyeing process using natural dyes from Bixa orellana (annatto) through response surface methodology. Central composite design experiments highlight the significant enhancement of color outcomes achieved through microwave treatment. For silk, the optimal conditions (80 °C for 40 min) with annatto extract yield a color strength (K/S) of 17.8588, while wool achieves a K/S of 7.5329. Introducing eco-friendly bio-mordants, such as pomegranate peel and red sumac tannins, enhances color strength. Pre-dyeing treatments with 2% red sumac, 1.5% pomegranate peel, and weld flower extracts for silk produce high color strength, with K/S values of 16.4063, 16.3784, and 12.1658, respectively. Post-dyeing, the K/S values increase to 40.1178, 17.4779, and 21.6494. Wool yarn exhibits similar improvements, with pre-dyeing K/S values of 13.1353, 13.5060, and 16.3232, escalating to 10.5892, 15.3141, and 23.4850 post-dyeing. Furthermore, this research underscores improved colorfastness properties, including notable enhancements in light, wash, and rubbing fastness for both silk fabric and wool yarn. These findings underscore the efficacy of the proposed sustainable dyeing methods, offering valuable insights for eco-friendly textile production.

Detoxification and enhancement of in vitro rumen digestibility of exhausted olive pomace wastes through alkaline hydrogen peroxide treatment

Abstract Background Due to the sharp rise in animal feed costs, funding alternatives to substitute high-cost raw materials used in animal feed is a persistent need. This study investigated the effect of alkaline hydrogen peroxide pretreatment as straightforward non-toxic technology to enhance the in vitro rumen digestibility of exhausted olive pomace (EOP), an abundant agricultural waste, to be suitable as animal feedstock. It examined the efficiency to eliminate the toxic phenolic content and minimize lipid oxidation of EOP. Results The pretreatment was first optimized using a central composite experimental design. Under the optimized conditions (1.6% H2O2, 5% NaOH), the measured phenolic content was 1.51 ± 0.03 mg/100 g dry weight (DW) for treated olive pomace (TOP) versus 4.91 ± 0.06 mg/100 g for the untreated one. The pretreatment showed that approximately 25% of the lignin was removed. Crude proteins, neutral detergent fibers, and acid detergent fibers yields of TOP were, respectively, 3.320 ± 0.05, 75.24 ± 0.23, and 54.05 ± 0.35 g/100 g of DW, significantly more important than those of untreated EOP. The enzymatic hydrolysis with a cellulase-based cocktail (Celluclast15 FPU/gDW), recorded a 48% of reducing sugar yield for TOP against 33% for EOP. When the in vitro organic matter digestibility (IVOMD) was assayed, the potential gas production of TOP (41.371 ml/g DM) was significantly higher than EOP (25.771 ml/g DM). The metabolizable energy of TOP (9.28 kcal/kg DM) was higher than that of EOP (7.78 kcal/kg DM). Conclusions The present study revealed that alkaline hydrogen peroxide (AHP) could be an efficient treatment for the detoxification and enhancement of in vitro rumen digestibility of olive pomace. This straightforward approach demonstrated that treated olive pomace waste may be well valorized as suitable animal feedstock. Graphical Abstract

Development and assessment of rutin loaded transfersomes to improve ex vivo membrane permeability and in vitro efficacy

The melanoma is the most dangerous kind of skin cancer begins in the melanocytes, or cells that make melanin, the pigment that gives your skin its color. Due to the need of local effect topical administration of anticancer drugs could be the best option for clinical therapy. Present study aimed to formulate transfersomes to enhance the skin penetration of rutin (Rtn). Rutin loaded transfersomes (RtnTFs) were formulated by employing central composite design (CCD) of experiment and comprising of various ratios of phospholipid 90H and sodium deoxycholate as independent variables. The assessment of critical parameters suggested higher encapsulation of Rtn and improved stability of formulation with significant drug release (P < 0.05). The RtnTFs shows higher cell inhibition on Murine skin Melanoma cell line (B16–F10). Further, formulated RtnTFs were incorporated in transdermal patches (TPs) to enhance skin deposition. However the higher deposition of about 0.921 ± 0.23 mg/cm3 of Rtn was observed. RtnTFs-TPs exhibited ideal morphological characteristics in scanning electron microscopic images. Ex-vivo skin diffusion studies revealed the sustained release of about 98 ± 0.26 % drug at the end of 36 h (P < 0.05). Skin irritancy study demonstrated the suitability of RtnTFs-TPs for dermal delivery and with higher stability. Hence the topical delivery with delayed release of drug by enhancing the solubility could be the promising strategy for efficient delivery of anticancer agents.

Optimizing the Antimicrobial Activity of Sodium Hypochlorite (NaClO) over Exposure Time for the Control of Salmonella spp. In Vitro.

Fish is a nutritionally rich product; however, it is easily contaminated by pathogenic microorganisms, such as Salmonella spp. Therefore, this study aimed to identify the best concentration of sodium hypochlorite (NaClO), exposure time, and water temperature that allow the most effective antimicrobial effect on the viable population of Salmonella spp. Thus, Salmonella Enteritidis ATCC 13076 and Salmonella Schwarzengrund were exposed to different time frames, ranging from 5 min to 38.5 min, temperatures between 5 and 38.5 °C, and NaClO concentrations ranging from 0.36 to 6.36 ppm, through a central composite rotational design experiment (CCRD). The results demonstrated that the ATCC strain exhibited a quadratic response to sodium hypochlorite when combined with exposure time, indicating that initial contact would already be sufficient for the compound's action to inhibit the growth of the mentioned bacteria. However, for S. Schwarzengrund (isolated directly from fish cultivated in aquaculture), both NaClO concentration and exposure time significantly influenced inactivation, following a linear pattern. This suggests that increasing the exposure time of NaClO could be an alternative to enhance Salmonella elimination rates in fish slaughterhouses. Thus, the analysis indicates that the Salmonella spp. strains used in in vitro experiments were sensitive to concentrations equal to or greater than the recommended ones, requiring a longer exposure time combined with the recommended NaClO concentration in the case of isolates from aquaculture.

Decolorisation of textile wastewater using biosynthesised iron oxide nanomaterials and Optimisation by Response Surface Methodology

AbstractIn this study, the bacteria (Pseudomonas sp.) was isolated and cultured for biogenic fabrication of Fe3O4 (synthesised using bacterial cell mass) and Fe3O4@ME (synthesised using bacterial extracts) nanoparticles. The biomolecules of the bacterial extract function as a reducing and capping agent, giving the nanoparticle surface negative charges, according to the FTIR and Z potential analysis. The parameters were optimised and screened for indigo blue (IB) dye adsorption onto Fe3O4 and Fe3O4@ME nanoparticles. This work used the Design of the Experimental (DoE) method rather than the conventional one‐variable‐at‐a‐time method. The central composite design (CCD) experiment consisted of 13 experimental runs, and an analysis of variance (ANOVA) was performed to analyse the results. The models for IB dye removal using Fe3O4 and Fe3O4@ME nanomaterials showed adjusted R2 values of 0.99 and 0.99 and predicted R2 values of 0.97 and 0.99, respectively, indicating good model fit. The optimum conditions required for 70 and 64 % colour removal for Fe3O4 and Fe3O4@ME nanomaterials, respectively, are observed at 0.050 gm sorbent doses at the constant room temperature and contact time of 100 min.