Central Composite Design Tool Research Articles

Formulation and Optimization of Trandolapril Oro-dispersible Tablets using the Quality by Design (QbD) Approach

Introduction:: This study aims to use a Quality by Design (QbD) approach to formulate and optimize Trandolapriloro-dispersible tablets. The central composite design tool was utilized to assess the scientific understanding of independent input variables and output responses to construct a design space for regulatory flexibility. Oro-dispersible Tablets (ODT) can also be used to deliver drugs directly to the oral mucosa, bypassing first-pass hepatic metabolism and potentially accelerating the process. Methodology:: The concentrations of super disintegrant and dry compressible binder were selected as independent variables. Disintegration time in seconds and % friability was selected as dependent variables. Polynomial equations were used to predict the quantitative effect of independent variables at various levels on response variables. Results and Discussion: The pre-compression parameters suggested that the flow characteristics were quite excellent. All tablets prepared in the above experiments were evaluated for pharmaco-technical properties and found to be within the required limits using the direct compression method. The angle of repose of the dry blends from each formulation batch (F1 to F9) ranged from 29.03° to 33.67°. All formulation batches had a loose bulk density of 0.31 + 0.07 to 0.37 + 0.91 g/cm3 and a tapped density of 0.41+ 0.02 to 0.46+ 0.16 g/cm3, respectively. The compressibility index was determined to be between 1.65 + 0.17 to 19.93 + 0.47 . Hausner's ratio was between 1.14 + 0.88 to 1.19 + 0.32. The thickness of the tablets ranged from 2.07 + 0.54 to 2.52 + 0.12 mm. The tablets were found to have a hardness of 3.08 + 0.14 to 3.67 + 0.41 kg/cm2. The weight of the tablets prepared ranged from 50 + 0.09 to 52 + 0.56 mg on average. Tablet friability was 0.52 + 0.54 to 0.83 + 0.10 %, and the disintegration time ranged between 27 and 58 seconds. All of these parameters were found under the acceptable limit of pharmacopoeias. The increase of Crospovidone concentration decreased the disintegration time and increased % friability. Whereas increasing the concentration of microcrystalline cellulose increased the disintegration time and decreased the % friability. Contour plots clarified the link between independent and dependent variables. The most cost-effective batch was chosen based on these plots within the desired range because the actual and projected values suggested by the full model were very close to each other; the statistical model is mathematically valid. Conclusion:: The results showed that the proposed design for developing trandolapriloro-dispersible tablets with optimal properties was effective.

Modulation of the best conditions for improved engine performance and reduced exhaust emissions using an eco-friendly nano additive in parsley biodiesel blend

This research work aims to assess the optimal conditions that would lower exhaust emissions and enhance engine performance using a green synthesized silica nano additive added parsley biodiesel blend. Hence, the process variables were optimized and the interactive influence of engine speed, engine load, and biodiesel blend (B20SNP) concentration was examined using the central composite design tool integrated into the response surface methodology design. The findings of this study showed that the studied variables had a substantial effect on the responses. Also, the ideal conditions for improved efficiency and reduced emissions were predicted to be B20SNP (100 ppm), engine speed (1458.60 rpm), and engine load (98.07%) while the best responses for improved engine characteristics were BTE (31.91%), BSEC (5.97 MJ/kW), BSFC (0.388kg/kWh), HC (19.18%), NOx (198.21 ppm) and CO (0.050 %) at the desirability of 1.000. The results of the ANOVA analysis revealed that B20SNP had the most influence on the behavior of the investigated four-stroke single-cylinder diesel engine. Furthermore, the results of this study asserted that silica nanoparticles made from waste sugarcane bagasse greatly enhanced the diesel engine’s efficiency and reduced emission behavior.

Optimization of ultrasonication assisted alkaline delignification of coir pith using response surface methodology

Coconut coir pith constituting cellulose, lignin, and hemicellulose is considered as a replenishing and extensively available biomass for the manufacture of value-added chemicals and biofuels. The processability of coir pith has been limited by hemicellulose and lignin content which imparts high recalcitrance to the biomass. The study aims at ultrasonication assisted alkaline treatment of coir pith to attain maximum percent delignification. The process parameters were screened using Plackett Burman Design and the significant parameters were optimized using Central Composite Design tool in Response Surface Methodology. About 70.79 % delignification was achieved when biomass was treated at 180.45 °C for 151.54 min in 3.82 % sodium hypochlorite solution. Scanning electron microscopy (SEM), Fourier transform infra-red (FTIR) spectroscopy and X-ray diffraction (XRD) spectroscopy were employed to characterize the biomass. Water sorption and retention behavior of coir pith was also studied.

The effect of flux composition on tensile strength of re-engineered E308H-16 electrode

A stainless steel flux for manual metal arc welding (MMAW) has been developed. The coated electrode is a rutile electrode whose basic components are titanium (IV) oxide and stainless steel powder. Some of the other components were substituted; the more popular but expensive potassium silicate binder was replaced with readily available sodium silicate binder. For the binder to perform effectively, it was enriched with potassium carbonate, which was sourced locally from palm bunch. Cellulose, a good gas former was replaced with starch, which was gotten from cassava. The components were sieved into 75 µm particle size. The experimental design was set up using Central Composite Design in Design Expert software. The design varied the percentage composition of calcium carbonate, binder, titanium (IV) oxide, silicon (IV) oxide, and stainless steel powder. Twenty-six (26) test samples were produced using the central composite design tool of the design expert software and tested for tensile strength. The experimental results were analyzed and optimized using Response Surface Methodology and Validated using the ANOVA tool of the Design Expert software. An optimal composition of 10% CaCO3, 13% Binder, 13% Titanium oxide, 12% silicon (IV) oxide, and 36% stainless steel powder were obtained to give a corresponding 539.7 N/mm2 tensile strength.

Optimization of process condition to improve percentage purity of aloe emodin from aloe vera by extraction using response surface methodology with the central composite design tool

Extraction is a common separation technique in major chemical and pharmaceutical industries, and it has traditionally been a recommended method for separating active ingredients. The objectives of this research work were to optimize extraction conditions for the separation of derivatives of anthraquinone compounds, especially Aloe Emodin (AE) from Aloe-Vera latex (AVL) using the tool response surface methodology (RSM). This study used three process variables at different levels (20 experimental design runs) proposed by RSM with central composite design (CCD). Multiple regression analysis was used to produce a quadratic polynomial equation to predict extraction condition. The significant effects of the components were investigated using analysis of variance (ANOVA). The first series of single factor studies determined the range of independent variables, including extraction temperature (60-80°C), agitation speed (750-1250 rpm), and solid loading (10-20 gm). Based on the outcomes of single factor trials, the actual values of the independent variables coded were chosen. The optimum conditions for extraction variables for AE were found to be 77.66 °C (±1 °C), 1015 rpm (±10 rpm), and 20.15 gm (±0.01 gm). The maximum experimental purity of AE attained under these optimized settings was 95.36 percent, which was quite near to projected values.

Representation of gas metal arc pulsed welding process behavior on bead geometry: a study of leading variables

Gas metal arc welding is one of the most influential processes in the production and repair of structures and equipment; therefore, the need to improve the productivity and quality of welded joints has led to the development of techniques for good control of welding parameters. Also, the development of semi-automatic welding processes led to the control of one of the variables such as pulsed current; this technique is characterized by a lower heat input and lower energy expenditure, which directly influences the structural quality of the welded joint and the geometry of the weld bead. This work focused on evaluating the effects of various welding operating parameters using the central composite design tool based on the response surface methodology; next, the experimental development employed an inverter type power source for weld depositions, a commercial grade Stargold clean 96% Ar and 4% CO2 shielding gas at the rate of 15 L/min stationary arc, a 1.2 mm metal cored wire for welding deposit and a carbon steel base plate with a thickness of 6 mm. During the welding process, the torch was kept at a 90° inclination and a 16 mm stroke. To examine the adequacy of the empirical models and the significance of the regression coefficients, the variance analysis was employed. Consequently, the graphs were obtained through the determination of the model; from the statistical results obtained, it was shown that the above models were adequate to predict the weld width, bead height, and penetration within the range of variables studied. Furthermore, it was observed that the wire feed rate it has a very marked effect on weld bead geometry, followed by frequency pulse and peak current; finally, the effectiveness of employing these methodologies for the management of variables attributing to the execution of welding tasks with higher accuracy was demonstrated.

Optimization and Process Modeling of Viscosity of Oil Based Drilling Muds

The viscosity of oil-based drilling mud was optimized and modeled in this study. Imported bentonite and local clay additives, and diesel oil (base fluid) were used to prepare two muds; oil-based mud with bentonite (OBMB) and oil-based mud with clay (OBMC). The local clay was beneficiated with hydrochloric acid (HCl) and then characterized using an x-ray fluorescence (XRF) spectrometer. The result of the characterization revealed that the local clay is more silica (SiO2) than kaolin. The interactive effects of three operating conditions, temperature, aging time, and bentonite/clay dosage, respectively, on the viscosity of each mud were determined. The Response surface methodology (RSM) of the central composite design tool of Design Expert software (version 12) was employed to optimize the viscosity of each mud. The RSM carried out revealed the interaction between the three operating variables of temperature, time, and dosage of bentonite/clay and their impact on the viscosity of each mud. Optimum viscosity of 19.3 cP for OBMB and 25.9 for OBMC were obtained at temperature of 313K, aging time of 30 minutes and bentonite/clay dosage of 9 wt%. Analysis of variants (ANOVA), mathematical modeling, and graphical plots further established the actual interaction between the response-viscosity of each mud and the considered process factors. The generated models revealed linear, interactive, and quadratic equations which adequately described the relationship between the viscosity of each mud and the considered factors of temperature, time, and dosage. The experimental data and the predicted results were compared, and the model predicted values are in good agreement with the experimental results. Doi: 10.28991/HEF-2021-02-04-09 Full Text: PDF

Steel work design, production and analysis of a fish feed mixing machine

As Nigeria props up her desire to boost local manufacturing and production industries, the need for proper design of an efficient and reliable fish feed mixing machine for safe and economic use cannot be overemphasized, as an efficient and reliable machine would minimize deterioration and losses during production to deliver good quality products (fish feeds) obtainable at the lowest production cost as well as the shortest production time. A blade-type fish feed mixer has been designed and fabricated. The mixer runs with a 1.5Hp, single-phase electric motor and has a production capacity of 50 kg/h. It was designed with the aid of auto cad software and fabricated using stainless steel and galvanized steel materials. All the fixed metal parts were joined using electric arc welding, while the detachable parts were fastened with an adequate size of bolt and nut. he effect of mixing time and speed on the homogeneity of the feed mix obtained was ascertained using the Central Composite Design tool of the Design-Expert software was used. The result showed that mixing time has a positive effect on the homogeneity of fish feed with its peak at about 25 minutes. the mixing speed also gives a positive effect with its peak at 220rpm. However, mixing speed beyond 220rpm gives a negative effect on the homogeneity of the feed. With the aid of the Auto cad inventor software, stress analyses were conducted on the conveyor assembly, considering gravity forces, body forces, remote forces, and moment. On testing, the efficiency of the machine was evaluated to be 75 %. The finite element analysis gave a maximum von mixes stress of 53.7697 MPa for the assembly which is not up to half of the yield strength of the material used for the machine. Hence, the machine is safe and durable.

Optimization of Composition of Selected Biomass for Briquette Production

In this study, investigations were carried out on the energy evaluation, performance analysis and optimization of briquettes produced from biomass wastes (rice-husk and sawdust) and their composites using starch and clay as binders. The proximate compositions of the briquettes were determined following ASTM analytical methods. The moisture content of rice husk and sawdust before briquettes was 20wt.% and 15wt.% respectively. The briquettes produced from bio-waste material of homogeneous particle sizes of 0.5mm and two binders of a percentage of 90:10 which were sun-dried, prepared and moisturized, were reduced to 5wt.% and compressed for the production of briquettes. The energy evaluation of the briquettes was performed using an oxygen bomb calorimeter and the performance test of the briquettes was carried out. Design Expert Central Composite Design Tool was used in the design and Response surface methodology was used to optimize the energy values of rice-husk/sawdust composite briquettes with clay and starch as binders, after which composite briquette made of mahogany sawdust/rice-husk were produced using the optimum condition values of 15% binder starch, 28% rice-husk and 9Mpa compaction pressure. The results showed that composite briquettes of mahogany sawdust and rice-husk produced with starch had a maximum energy value of 5.69kcal/g, while those made with clay had a minimum energy value of 3.35kcal/g. However, the experimental result was less than the predicted optimum value of 2%. This shows that composite briquette made from mahogany sawdust/rice-husk has better energy efficiency than other briquettes considered and it has been observed that starch is a better bonding material than clay. Briquetting technology has great potential to transform waste biomass in affordable, effective and environmentally safe, high-quality solid fuel for households and industry use.

Effect of cane wood and palm kernel fibre filler on the compressive strength and density of automobile brake pad

The study on the effect of cane wood and palm kernel as filler materials on the compressive strength and density of an automobile brake pad has been done. The Central Composite Design tool of the Design Expert 8 software was used to design percentage composition of the test samples for 20 experimental runs. To ascertain how well the factors fit in the design, the lack of fit test was performed. The analysis of variance shows that the developed models are significant and quadratic, showing that both materials affect the responses. On optimization, optimal compressive strength and density of 107.3 MPa and 1.73 g/cm3 were obtained for the composition of 30% resin content, 21.329% palm kernel fibre content and 40% cane wood content. Thus, the combination of cane wood and palm kernel fibre as filler material for brake pad production will give an automobile brake pad with good compressive strength and density.

Formulation and Optimization of Piroxicam Orodispersible Tablets by Central Composite Design

Objective: The present work was designed to formulate and optimize Orodispersible tablets of Piroxicam using QbD approach. The central composite design tool was used to evaluate the scientific understanding of input and output variables to construct design space for regulatory flexibility. Methodology: The concentrations of super disintegrants were selected as independent variables. The dependent variables selected were in vitro dispersion time and percentage drug release. The quantitative effect of independent variables at different levels on response variables was predicted using polynomial equations. The model was found to be nonlinear and the curvature effect was significant. Therefore study resorted to composite design for optimization. Results and Discussion: DSC studies indicated drug and excipients were compatible. Precompression parameters indicated fairly good flow properties. Tablets were prepared by direct compression method and all the tablets prepared in the above studies were evaluated for pharmacotechnical properties and were found to be within specified limits. Increase in the concentration of Sodium starch glycolate (SSG), Crospovidone (CP) decreased the in vitro dispersion time and increased percentage drug release. Kinetic studies revealed that drug release from all formulations followed first order release. The relationship between independent variables and dependent variables was further elucidated using contour plots. Based on these plots most economical batch was decided which were in desired range. The statistical model is mathematically valid as the experimental values and predicted values suggested by the full model were relatively close to each other. Conclusion: The results demonstrated the effectiveness of the proposed design for development of Piroxicam orodispersible tablets with optimized properties. Key words: Piroxicam, Croscarmellose sodium (CCS), Sodium starch glycolate (SSG), Crospovidone (CP), Central composite design.

Erratum to: Evaluation of photosynthetic efficacy and CO2 removal of microalgae grown in an enriched bicarbonate medium.

Bicarbonate species in the aqueous phase is the primary source for CO2 for the growth of microalgae. The potential of carbon dioxide (CO2) fixation by Chlorella pyrenoidosa in enriched bicarbonate medium was evaluated. In the present study, effects of parameters such as pH, sodium bicarbonate concentration and inoculum size were assessed for the removal of CO2 by C. pyrenoidosa under mixotrophic condition. Central composite design tool from response surface methodology was used to validate statistical methods in order to study the influence of these parameters. The obtained results reveal that the maximum removal of CO2 was attained at pH 8 with sodium bicarbonate concentration of 3.33 g/l, and inoculum size of 30 %. The experimental results were statistically significant with R 2 value of 0.9527 and 0.960 for CO2 removal and accumulation of chlorophyll content, respectively. Among the various interactions, interactive effects between the parameters pH and inoculum size was statistically significant (P < 0.05) for CO2 removal and chlorophyll accumulation. Based on the studies, the application of C. pyrenoidosa as a potential source for carbon dioxide removal at alkaline pH from bicarbonate source is highlighted.

Evaluation of photosynthetic efficacy and CO2 removal of microalgae grown in an enriched bicarbonate medium.

Bicarbonate species in the aqueous phase is the primary source for CO2 for the growth of microalgae. The potential of carbon dioxide (CO2) fixation by Chlorella pyrenoidosa in enriched bicarbonate medium was evaluated. In the present study, effects of parameters such as pH, sodium bicarbonate concentration and inoculum size were assessed for the removal of CO2 by C. pyrenoidosa under mixotrophic condition. Central composite design tool from response surface methodology was used to validate statistical methods in order to study the influence of these parameters. The obtained results reveal that the maximum removal of CO2 was attained at pH 8 with sodium bicarbonate concentration of 3.33 g/l, and inoculum size of 30 %. The experimental results were statistically significant with R 2 value of 0.9527 and 0.960 for CO2 removal and accumulation of chlorophyll content, respectively. Among the various interactions, interactive effects between the parameters pH and inoculum size was statistically significant (P < 0.05) for CO2 removal and chlorophyll accumulation. Based on the studies, the application of C. pyrenoidosa as a potential source for carbon dioxide removal at alkaline pH from bicarbonate source is highlighted.

Optimization of Process Parameters for Spray Drying of Fermented Soy Milk

Generally used as an inexpensive source of high-quality protein with many other health-promoting properties, soy milk offers an interesting alternative when fermented. Fermentation with lactic acid bacteria brings about the value addition to soy milk, making a nutritious probiotic food product. Dehydration helps to achieve longer shelf life and easier transportation and storage, enabling wider distribution of the product. The present work pertains to optimization of process parameters for spray drying of fermented soy milk using response surface methodology (RSM). The process parameters studied include inlet air temperature, aspirator speed (air flow rate), feed flow rate, and atomization pressure. The experiments were designed using the central composite design tool. Residual moisture content was found to be low at higher inlet air temperature, lower feed flow rate, higher atomization pressure, and higher air flow rate. Porosity reduced with increased atomization pressure. Higher product yield was obtained at high air flow rate and low feed flow rate. The increase in the atomization pressure increases the cohesiveness between particles, resulting in reduced flowability. An increase in the inlet air temperature greatly reduces the viability and the isoflavone aglycone content in the product. Protein denaturation during the process was found to reduce the product solubility.