RMST-based multiple contrast tests in general factorial designs.

Several methods in survival analysis are based on the proportional hazards assumption. However, this assumption is very restrictive and often not justifiable in practice. Therefore, effect estimands that do not rely on the proportional hazards assumption are highly desirable in practical applications. One popular example for this is the restricted mean survival time (RMST). It is defined as the area under the survival curve up to a prespecified time point and, thus, summarizes the survival curve into a meaningful estimand. For two-sample comparisons based on the RMST, previous research found the inflation of the type I error of the asymptotic test for small samples and, therefore, a two-sample permutation test has already been developed. The first goal of the present paper is to further extend the permutation test for general factorial designs and general contrast hypotheses by considering a Wald-type test statistic and its asymptotic behavior. Additionally, a groupwise bootstrap approach is considered. Moreover, when a global test detects a significant difference by comparing the RMSTs of more than two groups, it is of interest which specific RMST differences cause the result. However, global tests do not provide this information. Therefore, multiple tests for the RMST are developed in a second step to infer several null hypotheses simultaneously. Hereby, the asymptotically exact dependence structure between the local test statistics is incorporated to gain more power. Finally, the small sample performance of the proposed global and multiple testing procedures is analyzed in simulations and illustrated in a real data example.

Investigating Best Practices for Ecological Momentary Assessment: Nationwide Factorial Experiment.

BACKGROUND: Ecological momentary assessment (EMA) is a measurement methodology that involves the repeated collection of real-time data on participants' behavior and experience in their natural environment. While EMA allows researchers to gain valuable insights into dynamic behavioral processes, the need for frequent self-reporting can be burdensome and disruptive. Compliance with EMA protocols is important for accurate, unbiased sampling; yet, there is no "gold standard" for EMA study design to promote compliance. OBJECTIVE: The purpose of this study was to use a factorial design to identify optimal study design factors, or combinations of factors, for achieving the highest completion rates for smartphone-based EMAs. METHODS: Participants recruited from across the United States were randomized to 1 of 2 levels on each of 5 design factors in a 2×2×2×2×2 design (32 conditions): factor 1-number of questions per EMA survey (15 vs 25); factor 2-number of EMAs per day (2 vs 4); factor 3-EMA prompting schedule (random vs fixed times); factor 4-payment type (US $1 paid per EMA vs payment based on the percentage of EMAs completed); and factor 5-EMA response scale type (ie, slider-type response scale vs Likert-type response scale; this is the only within-person factor; each participant was randomized to complete slider- or Likert-type questions for the first 14 days or second 14 days of the study period). All participants were asked to complete prompted EMAs for 28 days. The effect of each factor on EMA completion was examined, as well as the effects of factor interactions on EMA completion. Finally, relations between demographic and socioenvironmental factors and EMA completion were examined. RESULTS: Participants (N=411) were aged 48.4 (SD 12.1) years; 75.7% (311/411) were female, 72.5% (298/411) were White, 18.0% (74/411) were Black or African American, 2.7% (11/411) were Asian, 1.5% (6/411) were American Indian or Alaska Native, 5.4% (22/411) belonged to more than one race, and 9.6% (38/396) were Hispanic/Latino. On average, participants completed 83.8% (28,948/34,552) of scheduled EMAs, and 96.6% (397/411) of participants completed the follow-up survey. Results indicated that there were no significant main effects of the design factors on compliance and no significant interactions. Analyses also indicated that older adults, those without a history of substance use problems, and those without current depression tended to complete more EMAs than their counterparts. No other demographic or socioenvironmental factors were related to EMA completion rates. Finally, the app was well liked (ie, system usability scale score=82.7), and there was a statistically significant positive association between liking the app and EMA compliance. CONCLUSIONS: Study results have broad implications for developing best practices guidelines for future studies that use EMA methodologies. TRIAL REGISTRATION: ClinicalTrials.gov number NCT05194228; https://clinicaltrials.gov/study/NCT05194228.

Green micellar factorial design optimized first derivative synchronous spectrofluorimetric method for tripelennamine and diphenhydramine determination in pharmaceutical gel.

A green micellar synchronous spectrofluorimetric method was developed and validated for simultaneous determination of tripelennamine hydrochloride and diphenhydramine in bulk and combined pharmaceutical formulation. Synchronous fluorescence of tripelennamine hydrochloride and diphenhydramine was determined using Δλ = 60 nm. The first derivative of synchronous fluorescence was computed to resolve overlap in the synchronous fluorescence spectra. Tripelennamine hydrochloride was quantified at 375 nm, whereas diphenhydramine was quantified at 293 nm; each is the zero-crossing point of the other. As diphenhydramine exhibited weak native fluorescence, micelle enhancement upon incorporation of sodium dodecyl sulfate was considered. Two-level full factorial design was carried out to optimize experimental parameters. Optimum conditions involved using SDS (2% w/v) along with Teorell and Stenhagen buffer (pH 9). The method was found to be linear over the range 0.2-4.5 and 0.2-5 µg/mL for tripelennamine and diphenhydramine, respectively, with limits of detection 0.211 and 0.159 µg/mL. The method was successfully applied for simultaneous determination of tripelennamine hydrochloride and diphenhydramine in laboratory-prepared gel containing all possible excipients with mean percent recoveries ±SD 100.59 ± 0.79 and 98.99 ± 0.98 for tripelennamine hydrochloride and diphenhydramine, respectively. The proposed method was proved to be eco-friendly using different greenness assessment tools.

Enhanced low-cost lipopeptide biosurfactant production by Bacillus velezensis from residual glycerin.

Biosurfactants (BSFs) are molecules produced by microorganisms from various carbon sources, with applications in bioremediation and petroleum recovery. However, the production cost limits large-scale applications. This study optimized BSFs production by Bacillus velezensis (strain MO13) using residual glycerin as a substrate. The spherical quadratic central composite design (CCD) model was used to standardize carbon source concentration (30 g/L), temperature (34 °C), pH (7.2), stirring (239 rpm), and aeration (0.775 vvm) in a 5-L bioreactor. Maximum BSFs production reached 1527.6 mg/L of surfactins and 176.88 mg/L of iturins, a threefold increase through optimization. Microbial development, substrate consumption, concentration of BSFs, and surface tension were also evaluated on the bioprocess dynamics. Mass spectrometry Q-TOF-MS identified five surfactin and two iturin isoforms produced by B. velezensis MO13. This study demonstrates significant progress on BSF production using industrial waste as a microbial substrate, surpassing reported concentrations in the literature.

Quality-by-design driven approach in the formulation of an anti-ulcer and gastro-protective oral suspension.

OBJECTIVE: This work aims to present a Quality-by-Design (QbD) step-by-step methodology to formulate anti-ulcer and gastro-protective oral suspensions. METHODS: Sucralfate was used as a drug model. The Quality Target Product Profile was established early during preformulation. Viscosity, resuspendability, pH, and density were assessed through the screening of several suspension platforms based on different prototype compositions. A compatibility study between the active pharmaceutical ingredient and the excipients was performed by thermal analysis and infrared spectroscopy. An Ishikawa fishbone diagram and Failure Mode and Effect Analysis were employed to identify the Critical Material Attributes (CMAs), Critical Process Parameters (CPPs), and Critical Quality Attributes (CQAs). CMAs' and CPPs' impact on identified CQAs was further assessed through a 22 full factorial experimental design at normal conditions after manufacture and one month at super-accelerated stress conditions. Results: The lead prototype exhibited no physicochemical incompatibilities. The risk assessment tools revealed that the concentration of the wetting agent and the total concentration of thickening agents represented critical factors for the quality profile of the preparation in terms of viscosity. The optimized formulation comprising 1.125 w/v% total concentration of Natrosol 250 HX and Avicel RC 591 exhibited an enhanced performance according to the established profile. CONCLUSIONS: The analytical and physicochemical tests showed the robustness and compliance of the final preparation with the quality profile. The proposed step-by-step methodology based on QbD, Design of Experiments, and Quality Risk Management presented in our research holds practical implications for local industries and formulation scientists involved in the development of oral suspensions.

Improvement of Bioavailability of Sildenafil Citrate Through Taste Masked Orodispersible Film for Pulmonary Hypertension Management.

The oral bioavailability of sildenafil citrate is approximately 43%, primarily limited by the low aqueous solubility and first-pass effect. Considering the drug properties and biopharmaceutical considerations, this study aimed to develop an immediate release, taste masked orodispersible film (ODF) of sildenafil citrate for the efficient management of pulmonary arterial hypertension (PAH). The optimization was done by applying 32 full-factorial design. The drug-loaded film was prepared and evaluated for the physical and mechanical parameters like; thickness, disintegration time, tensile strength, elongation, swelling index, content uniformity, disintegration and in vitro drug release in pH 6.2 stimulated salivary fluid. The FTIR and DSC data proved excellent compatibility between the drug and polymers used. The time taken for disintegration by the optimized film was about 62.66 s, while the drug release was observed ~ 96% in 10 min. Pharmacokinetic studies exhibited better sildenafil plasma level (p < 0.05) and Cmax (p < 0.001) of orally disintegrating film which is significantly higher than the oral drug solution. The AUC0-8 (24874.425 ± 1234.45 ng. h/mL) in the oromucosal application was 1.2-fold more (p < 0.0001) than the control. The presence of sweetening and flavoring agents in the formulation masked the drug bitterness, resulting in a higher intake of the formulation in rats compared to the unmasked drug solution, as observed with in vivo taste masking studies. The importance of ODF as a feasible, effective, and optimal approach for delivering sildenafil citrate via oromucosal administration for the treatment of PAH was successfully highlighted by these results.

Verapamil-Loaded Cubosomes for Enhancing Intranasal Drug Delivery: Development, Characterization, Ex Vivo Permeation, and Brain Biodistribution Studies.

Verapamil hydrochloride (VRP), an antihypertensive calcium channel blocker drug has limited bioavailability and short half-life when taken orally. The present study was aimed at developing cubosomes containing VRP for enhancing its bioavailability and targeting to brain for cluster headache (CH) treatment as an off-label use. Factorial design was conducted to analyze the impact of different components on entrapment efficiency (EE%), particle size (PS), zeta potential (ZP), and percent drug release. Various in-vitro characterizations were performed followed by pharmacokinetic and brain targeting studies. The results revealed the significant impact of glyceryl monooleate (GMO) on increasing EE%, PS, and ZP of cubosomes with a negative influence on VRP release. The remarkable effect of Poloxamer 407 (P407) on decreasing EE%, PS, and ZP of cubosomes was observed besides its influence on accelerating VRP release%. The DSC thermograms indicated the successful entrapment of the amorphous state of VRP inside the cubosomes. The design suggested an optimized formulation containing GMO (50% w/w) and P407 (5.5% w/w). Such formulation showed a significant increase in drug permeation through nasal mucosa with high Er value (2.26) when compared to VRP solution. Also, the histopathological study revealed the safety of the utilized components used in the cubosomes preparation. There was a significant enhancement in the VRP bioavailability when loaded in cubosomes owing to its sustained release favored by its direct transport to brain. The I.N optimized formulation had greater BTE% and DTP% at 183.53% and 90.19%, respectively in comparison of 41.80% and 59% for the I.N VRP solution.

Formulation, Optimization and In-Vivo Characterization of Thermosensitive In-Situ Nasal Gel Loaded with Bacoside a for Treatment of Epilepsy.

The intranasal route has demonstrated superior systemic bioavailability due to its extensive surface area, the porous nature of the endothelial membrane, substantial blood flow, and circumvention of first-pass metabolism. In traditional medicinal practices, Bacopa monnieri, also known as Brahmi, is known for its benefits in enhancing cognitive functions and potential effects in epilepsy. This study aimed to develop and optimize a thermosensitive in-situ nasal gel for delivering Bacoside A, the principal active compound extracted from Bacopa monnieri. The formulation incorporated Poloxamer 407 as a thermogelling agent and HPMC K4M as the Mucoadhesive polymer. A 32-factorial design approach was employed for Optimization. Among the formulations. F7 exhibited the most efficient Ex-vivo permeation through the nasal mucosa, achieving 94.69 ± 2.54% permeation, and underwent a sol-gel transition at approximately 30.48 °C. The study's factorial design revealed that gelling temperature and mucoadhesive strength were critical factors influencing performance. The potential of in-situ nasal Gel (Optimized Batch-F7) for the treatment of epilepsy was demonstrated in an in-vivo investigation using a PTZ-induced convulsion model. This formulation decreased both the occurrence and intensity of seizures. The optimized formulation F7 showcases significant promise as an effective nasal delivery system for Bacoside A, offering enhanced bioavailability and potentially increased efficacy in epilepsy treatment.

Apixaban and clopidogrel in a fixed-dose combination: Formulation and in vitro evaluation.

Fixed-dose combination (FDC) products represent a novel, safe, and cost-effective formulation. Combined use of anticoagulant and antiplatelet medications is common among comorbid cardiovascular patients. This study aimed to formulate FDC tablets for Apixaban and Clopidogrel, as prophylaxis and treatment of thrombo-embolic events. FDC tablets were developed by combining small tablets of Immediate-Release Clopidogrel 75 mg and Extend-Release Apixaban 5 mg through direct compression and wet granulation. Particularly, Apixaban tablets were developed using design expert software, and various types and concentrations of polymers were entered. For Clopidogrel tablets, various diluents were used to develop the formulation. Then, the dissolution profile for each formula was studied. Finally, the optimized formulations were encapsulated within hard gelatin capsules. Apixaban formulation followed zero-order with super case Ⅱ transport mechanism as the dominant mechanism of drug release. The Apixaban drug release rate was affected by the type and concentration of the polymers in the formulation (P < 0.05). As the HPMC concentration was increased, Apixaban release was retarded. For, Clopidogrel, the formulated tablets with spray-dried lactose filler and sodium stearyl fumarate lubricant were found to be stable with good properties. In conclusion, the optimum formulation yielded Clopidogrel and extended-release Apixaban for 24 h with the desired in vitro drug dissolution.

AQbD-guided development and validation of an innovative extraction procedure and stability-indicating RP-HPLC method for quantification of posaconazole in tablet formulation.

OBJECTIVE: The objective of this work is to develop a stability-indicating HPLC method for the quantification of posaconazole (PCZ) in tablet formulation using an Analytical Quality by Design (AQbD) approach. MATERIALS AND METHODS: The development process involved the Design of Experiments (DOE) utilizing distinctive constraints mixture design for mobile phase ratio optimization and a 2-level factorial design for selection of extraction diluent compositions. Key responses measured included % assay and system suitability parameters. Method operable design regions (MODR) were determined, and final optimum conditions were selected. Forced degradation studies were conducted to assess method stability. RESULTS: The optimized HPLC method employed a Zorbax C18 column with a mobile phase consisting of pH 3.5 10mM phosphate buffer, acetonitrile, and methanol in a ratio of 30:53:17% v/v/v. The method demonstrated stability-indicating capabilities, with PCZ degradation observed in acidic and oxidative environments, while remaining stable in alkali. Peak purity analysis from Empower software confirmed the absence of interaction with degradants. Validation according to ICH Q2 (R2) guidelines showed precision, linearity over the range of 0.25 to 376µg/mL, and accuracy demonstrated through recovery studies from 50 to 150%. CONCLUSION: The developed HPLC method utilizing AQbD approach is specific, robust, precise, and accurate for the quantification of PCZ in tablet formulations, thus suitable for routine analysis.

Quality by design-based capillary electrophoresis method development for the quantitative analysis of four iridoid compounds in Gentiana macrophylla Radix.

In this study, the capillary electrophoresis-photodiode array detector was employed for the analysis of four iridoid compounds in Gentiana macrophylla Radix (RGM), and the method was optimized based on the concept of analytical quality by design (AQbD). The peak areas relative standard deviation (n = 3) and resolution of the four analytes were selected as critical method attributes. Fractional factorial design test combined with Pareto analysis were employed to screen critical method parameters (buffer concentration, pH, sodium dodecyl sulfate [SDS] micelle concentration, temperature, and voltage). Subsequently, three main factors (buffer concentration, buffer pH, and SDS concentration) were selected by central composite design test for constructing the design space. The optimal separation conditions as follows: capillary column (50.2 cm × 50 µm, detection length 40 cm). Working background electrolyte consisted of 51 mmol/L borax solution (pH = 9.47) and 40 mmol/L SDS. The samples were injected by pressure (5 s at 0.5 psi) and the detection was performed at 254 nm. Applied voltage was 20 kV and column temperature was 23°C. The developed method is rapid and reliable for the quantitative analysis of four iridoid compounds in RGM, providing a reference for the application of AQbD concept in the analysis of natural products.

Step-by-step full factorial design to optimize a quantitative sandwich ELISA.

In this work, a quantitative sandwich ELISA was optimized, through a full factorial design of experiments (DOE) in successive steps of a preliminary protocol obtained by the method of one factor at a time (OFAT). The specificity of the optimized ELISA, the lower limit of quantification, the quantification range and the analytical sensitivity of the antigen quantification curve were evaluated, in comparison with the curve obtained from the preliminary protocol. The full factorial DOE was linked to a simple statistical processing, which facilitates the interpretation of the results in those laboratories where there is no trained statistician. The step-by-step optimization of the ELISA and the successive incorporation into the protocol of the best combination of factors and levels, allowed obtaining a specific immunoassay, with an analytical sensitivity 20 times greater and with a lower limit of antigen quantification that decreased from 156.25 at 9.766 ng/mL. As far as we know, there are no reports of optimization of an ELISA following the step-by-step scheme used in this work. The optimized ELISA will be used for the quantification of the TT-P0 protein, the active principle of a vaccine candidate against sea lice.

Pleurotus pulmonarius: a protease-producing white rot fungus in lignocellulosic residues.

The production of proteases by white rot fungi, such as those of the genus Pleurotus, is related to the degradation of wood proteins, the substrate on which these fungi grow in the environment. From the point of view of production, they are still little explored for this purpose. A selection of agro-industrial residues highlighted corn bagasse as the best substrate for solid-state protease production using the basidiomycete Pleurotus pulmonarius. The enzyme production was maximized through a factorial design, where the enzyme activity increased from 137.8 ± 1.9 to 234.1 ± 2.7 U/mL. Factors such as temperature stability, pH, and chemical reagents were evaluated. The optimum temperature was 45 °C, showing low thermal stability at higher temperatures. The enzyme inhibition occurred by Mn2+ (50.3%) and Ba2+ (76.4%); SDS strongly inhibited the activity (82.4%), while pepstatin A partially inhibited (56%), suggesting an aspartic protease character. Regarding pH, the highest protease activity was obtained at pH 5.5. Partial characterization resulted in apparent values of the KM and Vmax constants of 0.61 mg/mL and 1.79 mM/min, respectively.

Effects of Behavioral Intervention Components for African American/Black and Latino Persons Living with HIV with Non-suppressed Viral Load Levels: Results of an Optimization Trial.

There is an urgent need for efficient behavioral interventions to increase rates of HIV viral suppression for populations with serious barriers to engagement along the HIV care continuum. We carried out an optimization trial to test the effects of five behavioral intervention components designed to address barriers to HIV care continuum engagement for African American/Black and Latino persons living with HIV (PLWH) with non-suppressed HIV viral load levels: motivational interviewing sessions (MI), focused support groups (SG), peer mentorship (PM), pre-adherence skill building (SB), and navigation with two levels, short (NS) and long (NL). The primary outcome was HIV viral suppression (VS) and absolute viral load (VL) and health-related quality of life were secondary outcomes. Participants were 512 African American/Black and Latino PLWH poorly engaged in HIV care and with detectable HIV viral load levels in New York City, recruited mainly through peer referral. Overall, VS increased to 37%, or 45% in a sensitivity analysis. MI and SG seemed to have antagonistic effects on VS (z = - 1.90; p = 0.057); the probability of VS was highest when either MI or SG was assigned, but not both. MI (Mean Difference = 0.030; 95% CI 0.007-0.053; t(440) = 2.60; p = 0.010) and SB (Mean Difference = 0.030; 95% CI 0.007-0.053; t(439) = 2.54; p = 0.012) improved health-related quality of life. This is the first optimization trial in the field of HIV treatment. The study yields a number of insights into approaches to improve HIV viral suppression in PLWH with serious barriers to engagement along the HIV care continuum, including chronic poverty, and underscores challenges inherent in doing so.

Phyto-assisted synthesis of CuO/industrial waste derived biochar composite for adsorptive removal of doxycycline hydrochloride and recycling of spent biochar as green energy storage device.

The highest exposure of Endocrine disrupting compounds (EDC) into the water bodies as a result of extensive production and application of Covid-19 related drugs is a growing concern now a days. Herein, a novel nanocomposite material was developed by impregnating green synthesized copper oxide nanoparticles on the porous surface of fabric waste derived biochar to eliminate the concerned EDCs along with a sustainable disposal strategy for the spent adsorbent. Morphological characterizations by Field emission scanning electron microscopy confirmed the formation of hierarchical porous structured material. X-ray analysis revealed presence of both amorphous nature of biochar matrix as well as the crystalline nature attributed from monodispersion of copper oxide nanoparticles onto biochar surface. Batch sorption study showed removal of doxycycline hydrochloride (DOX) of >97% after 2 h at pH 7, 30 mg L-1 initial concentration of DOX and 2 g L-1 of adsorbent dose at room temperature after a two-step optimization process. Spectroscopic study and Raman shift suggested that pore filling, strong complexation and electrostatic interactions maximise the adsorption of DOX in the CuO/biochar composite as compared to the pristine biochar. However disposal of spent adsorbent is a crucial aspect for the environment and therefore, a sustainable recycling strategy for DOX loaded adsorbent as electrode material has been proposed for the first time in this study. Maximum specific capacitance value was observed in the range of 221.9-297.3 F g-1 for the DOX loaded nanocomposite at 1 mV s-1 comparable with other reported heteroatom-doped carbonaceous material as electrode. Therefore the excellent adsorption capacity of green synthesized CuO/biochar composite and its recycling after DOX adsorption can be recommended as a sustainable solution for mitigation of pharmaceuticals from wastewater. A detail study on degradation of DOX into eco-friendly products and its cost-effectiveness would be beneficial to suggest appropriate mitigation strategy for such compounds.

Development, stability-indicating assessment, and evaluation of influential method conditions using a full factorial design for the determination of Nintedanib esylate-related impurities.

The design of an appropriate analytical method for assessing the quality of pharmaceuticals requires a deep understanding of science, and risk evaluation approaches are appreciated. The current study discusses how a related substance method was developed for Nintedanib esylate. The best possible separation between the critical peak pairs was achieved using an X-Select charged surface hybrid Phenyl Hexyl (150 × 4.6) mm, 3.5 µm column. A mixture of water, acetonitrile, and methanol in mobile phase-A (70:20:10) and mobile phase-B (20:70:10), with 0.1% trifluoroacetic acid and 0.05% formic acid in both eluents. The set flow rate, wavelength, and injection volumes were 1.0 ml/min, 285 nm, and 5 µl, respectively, with gradient elution. The method conditions were validated as per regulatory requirements and United States Pharmacopeia general chapter < 1225 >. The correlation coefficient for all impurities from the linearity experiment was found to be > 0.999. The % relative standard deviation from the precision experiments ranged from 0.4 to 3.6. The mean %recovery from the accuracy study ranged from 92.5 to 106.5. Demonstrated the power of the stability-indicating method through degradation studies; the active drug component is more vulnerable to oxidation than other conditions. Final method conditions were further evaluated using a full-factorial design. The robust method conditions were identified using the graphical optimization from the design space.

Potential of Antarctic lipase from Acinetobacter johnsonii Ant12 for treatment of lipid-rich wastewater: screening, production, properties and applications.

The present study aimed to screen and optimize lipase production by the Antarctic strain Acinetobacter johnsonii Ant12 for lipid-rich wastewater treatment. Lipase production was successfully enhanced threefold through optimization of culture conditions. The optimum crude lipase activity was observed at 50 °C with high stability in a wide temperature range. The lipase also exhibited high activity and stability in the presence of solvents, metal ions, and surfactants. The crude lipase was used for the treatment of lipid-rich wastewater, which poses a significant challenge, as traditional removal methods are often inefficient or non-eco-friendly. In this study, bioaugmentation with Ant12 resulted in substantial lipid reduction in synthetic as well as real-world wastewater. Multiple linear regression analysis showed that lipid concentration and time were the most significant factors influencing lipid degradation. Bioaugmentation of real-world wastewater with Ant12 cells resulted in 84% removal of lipids in 72 h, while its crude lipase degraded 73.7% of lipids after 24 h. Thus, the specific rate of lipid degradation was higher for crude lipase (0.095/h) than the whole cell treatment (0.031/h). Economic analysis revealed that crude lipase production was much cheaper, faster and more eco-friendly than purified or partially purified lipase production, which justifies its use in wastewater treatment. The high activity of enzyme also implicates its application as a detergent additive. In our knowledge, it is the first study to establish A. johnsonii isolate from Antarctica for lipid-rich wastewater treatment.

Quality by design tool-evaluated stability-indicating ultra-performance liquid chromatography method for the determination of drugs (ritonavir and darunavir) used to treat the human immunodeficiency virus/acquired immunodeficiency syndrome.

Ritonavir and darunavir were examined using a ultra-performance liquid chromatography (UPLC) approach in pharmaceutical dosage forms. The small number of analytical studies that are currently available do not demonstrate the method's stability or nature. The study sought to assess both chemicals using a stability-indicating approach with a relatively short run time. The HSS C18 (100 × 2.1 mm), 2-mm column was used for the chromatographic separation, and isocratic elution was used to achieve this. In the mobile phase, methanol and 0.01 M phosphate buffer (pH 4.0) were included in a 60:40 (v/v) ratio. Throughout the analysis, the flow rate was kept at 0.2 mL min-1 , and a photodiode array detector set to 266 nm was used to find the major components. The proposed method showed a linear response (r2  > 0.999), and the accuracy was between 98.0% and 102.0%. The precision data showed relative standard deviation ≤1.0%. The UPLC method for quantification of ritonavir and darunavir in pharmaceutical dosage forms using a very short run time of under a minute is the subject of the proposed article. To meet current regulatory criteria, the quality by design idea was used in the method performance verification.

Methylprednisolone 100 mg tablet formulation with pea protein: experimental approaches over intestinal permeability and cytotoxicity.

OBJECTIVE: This study was carried out to transform the hydrolyzed pea protein into a pharmaceutical tablet form by masking methylprednisolone. SIGNIFICANCE: This study provides some crucial contributions in showing how functional excipients such as pea protein, which are generally used in food industries, can be used in pharmaceutical product formulations and their effects. METHODS: Methylprednisolone was formulated using spray drying technology. Design Expert Software (Version 13) was used for the statistical analysis. The in vitro cytotoxic effects for NIH/3T3 mouse fibroblast cells were investigated by XTT cell viability assay. HPLC was used to analyze the Caco-2 permeability studies and dissolution tests. RESULTS: The optimum formulation was evaluated against the reference product by performing cytotoxicity and cell permeability studies. According to our test results, Papp (apparent permeability) values of Methylprednisolone were measured around 3 × 10-6 cm/s and Fa (fraction absorbed) values around 30%. These data indicate that Methylprednisolone HCl has 'moderate permeability' and our study confirmed that it could have belonged to BCS Class II-IV since both low solubility and moderate permeability. CONCLUSION: The findings offer valuable information to guide and inform the use of pea protein in pharmaceutical formulations. Significant effects on methylprednisolone tablet formulation designed with the philosophy of quality by design (QbD) of pea protein have been demonstrated by both in vitro and cell studies.

Effect of metals on mesophilic anaerobic digestion of strawberry extrudate in batch mode.

According to recent studies, the anaerobic digestion of strawberry extrudate is a promising option with potential in the berry industry biorefinery. However, the lack and/or unbalance of concentrations of metals in some agro-industrial residues could hamper methane production during the anaerobic digestion of these kinds of wastes. In this study, a fractional factorial design was applied to screen the supplementation requirements regarding six metals (Co, Ni, Fe, Cu, Mn, and Zn) for methane production from strawberry extrudate (SE). The logistic model was used to fit the experimental data of methane production-time. It allowed identifying two different stages in the anaerobic process and obtaining the kinetic parameters for each step. Maximum methane production obtained in the first (Bmax) kinetic stage, the methane production in the second stage (P), and the maximum methane production rates (Rmax) concluded a statistically significant effect for Ni and Zn. The second set of experiments was carried out with Ni and Zn through a central composite design to study the concentration effect in the anaerobic digestion process of the strawberry extrudate. The parameters P and Rmax demonstrated a positive interaction between Ni and Zn. Although, Bmax did not prove a statistically significant effect between Ni and Zn.