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Chemical engineering is an engineering branch that deals with the chemical production and manufacture of products that undergo chemical processes. This includes equipment design, creating systems and processes to refine raw material, as well as mixing, compounding, and processing chemicals to create products.
Chemistry and Chemical Engineering
Abstract
The first targeted Rho-associated protein kinase 2 inhibitor was Belumosudil (Rezurock). After at least two systemic treatments failed for chronic graft-versus-host disease in adults and children aged 12 and older, belumosudil (BLS) was approved on July 16, 2021. This study established a validated Ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) system to estimate BLS in HLMs and assess metabolic stability. Agilent C18 column was used to separate BLS and encorafenib (internal standard) in HLMs using an isocratic mobile phase. The electrospray ionization (ESI) source produced BLS parent ions. Multiple reaction monitoring identified and measured BLS daughter ions. The methodology was validated following FDA standards that assessed linearity, selectivity, accuracy, sensitivity, precision, extraction recovery, matrix effects, and stability. The accuracy and precision ranged from −1.42 to 12.50% between days and from −0.89 to 10.5% within a day. The created BLS calibration curve displayed a linearity in the range from 1 ng mL−1 to 3,000 ng mL−1. The LLOQ of 0.64 ng mL−1 showed the method's sensitivity. The AGEE program displayed that the approach was eco-friendly. In vitro half-life and intrinsic clearance of BLS were 17.55 min and 46.21 mL min−1 kg−1, demonstrating a high extraction ratio drug. These features can improve the metabolic stability of new derivatives compared to BLS, making them important in medication design.
Abstract
The magnitude of the interactions between two phases may be deduced from results collected by various experimental techniques. One of them is Inverse Gas Chromatography (IGC).
The aim of the work was to compose and examine various polymer blends of PVC/PMMA, PMMA/PS and PVC/PS. Behavior of these blends was characterized by using the Flory-Huggins parameters estimated by means of the IGC. Based on the obtained results, the miscibility of the components in the tested polymer blends was determined. Characteristics derived from IGC data were compared with literature data calculated from equilibrium solvent (methanol) absorption.
Abstract
In this study, a simple, fast, and sensitive stability indicating CE method was developed for the quantification of Triamterene (TRM) and Hydrochlorothiazide (HCT) in pharmaceutical preparations. Detection was achieved using a photo diode array detector, and the separation process was conducted in a capillary with an inner diameter of 75 µm and a length of 40 cm. Optimum conditions were achieved by using a run buffer of 15 mM borate containing 20 mM SDS at pH 9.00, and applying a potential of 25 kV. HCT and TRM exhibited migration times of approximately 2.75 ± 0.007 min and 4.61 ± 0.022 min, respectively, under these conditions. The developed method was validated by assessing parameters such as linearity, selectivity, precision, accuracy, sensitivity, stability, and robustness. To assess the selectivity of the method, HCT, TRM, and tablets containing these compounds were exposed to acidic, basic, oxidative, thermal, and photolytic stress conditions. Ultimately, the method was proved successfully in accurately determining HCT and TRM levels in tablets.
Abstract
This study examined the effect of grapefruit seed extract (GSE) (0%–3%) on the stability of total phenolic content (TPC), anthocyanins, and colour in aronia juice under heat treatments (60 °C, 80 °C for up to 120 min). TPC and anthocyanins were measured using spectrophotometry and HPLC. The highest TPC (8545.02 ± 355.55 GAE mg L−1) was measured in aronia juice with 1% GSE after 60 min at 80 °C. The highest anthocyanin retention (3178.75 mg L−1) was detected in the sample with 1% GSE after 5 min at 60 °C. Cyanidin-3-galactoside was the most abundant anthocyanin, followed by cyanidin-3-xyloside and cyanidin-3-arabinoside. Cyanidin-3-arabinoside showed the lowest heat stability, while cyanidin-3-galactoside was relatively more stable. This study, the first to evaluate anthocyanin half-life values in chokeberry juice, suggests that 1% GSE enhances colour stability during heat treatment, supporting its use as a natural food additive.
Abstract
ASP3026 is a recently formulated and highly selective inhibitor designed to target the ALK kinase. ASP3026 efficiently inhibited ALK kinase activity and demonstrated superior selectivity at a panel of Tyr-kinases compared to crizotinib. The target of this investigation was to establish a highly accurate, fast, green, and highly sensitive Ultra-high performance liquid chromatography- Tandem mass spectrometry (UHPLC-MS/MS) technique for assessing the concentration of ASP3026 in human liver microsomes (HLMs). In vitro incubation, the metabolic stability of ASP3026 in HLMs was evaluated using this known approach. The validation steps for the UHPLC-MS/MS analytical technique in the HLMs were performed along with the bio-analytical method validation guidelines settled by the US-FDA. To increase the ecological sustainability of the current UHPLC-MS/MS system, a lower flow rate of 0.3 mL min−1, a shorter elution duration of 1 min, and a reduced consumption of ACN have been implemented. A screening of the chemical structure of ASP3026 for hazardous alerts and metabolic lability was performed by the StarDrop package, that includes the DEREK and P450 modules. The analytical separation of ASP3026 and fenebrutinib (FNB) on the reversed phase Eclipse Plus C18 column was performed using an isocratic mobile phase approach. The calibration curve produced by the ASP3026 showed a linear association over the level range of 1–3,000 ng mL−1. A study was conducted to evaluate the precision and accuracy of UHPLC-MS/MS technology in evaluating both intra-day and inter-day variations. The accuracy exhibited a range of −1.56%–7.33% across various days, and a range of −0.78%–10.66% within the same day. The ASP3026 underwent in vitro half-life and intrinsic clearance measurements, yielding values of 14.32 min and 56.62 mL min−1 kg−1, correspondingly. According to in silico software research, using minor modifications to the piperazine component or substituting the group in drug design has the potential to improve the metabolic safety and stability of novel derivatives in comparison to ASP3026.
Abstract
In this experiment, ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was employed to quantify karacoline in mouse plasma following both intravenous and oral administration, thereby elucidating the pharmacokinetic characteristics of karacoline in mice. The analytes were extracted from mouse plasma using acetonitrile for protein precipitation. Chromatographic separation was performed on an HSS T3 column via gradient elution, with the mobile phase consisting of methanol and 0.1% formic acid in water. Quantification of karacoline and the internal standard (IS) was achieved using multiple reaction monitoring (MRM) mode. Six mice received an intravenous (i.v.) injection of karacoline at a dose of 1 mg kg−1, while another six mice were administered karacoline orally (p.o.) at a dose of 5 mg kg−1. The calibration curve for karacoline in mouse plasma ranged from 1 ng mL−1 to 2,500 ng mL−1. The intra-day precision was within 10.4%, and the inter-day precision was within 13.0%. Accuracy ranged from 89.1% to 107.5%, with recovery rates between 77.6% and 88.2%. Matrix effects were observed within the range of 77.6%–107.4%. This method successfully estimated the pharmacokinetics of karacoline, and its bioavailability was determined to be 27.2%, these are preliminary studies that require verification on a larger group of animals.
Abstract
An alternative to roller mills, a French-designed stone mill, was evaluated and compared with traditional laboratory roller mills through grinding performance. Developed by the Astrié brothers in the 1950s, the stone mill's slow-rotating granite stones purportedly preserve the full nutritional value of the grain. This study, conducted in collaboration with the Csoroszlya farm, compared flour from the same wheat batch ground by both an Astrié stone mill and a laboratory roller mill. Evaluations included the Pekar test for bran content, sieve analysis, measuring wet gluten content, and gluten index to assess protein quality. Rheological properties of the doughs were analyzed using Farinograph and Mixolab equipment, which indirectly also measured amylase enzyme activity. Results indicated that the stone mill produced flour with finer grain size, higher protein content, and higher enzyme presence, although challenges remain in achieving optimal gluten index and dough stability.
Abstract
In this study, a simple, rapid, and sensitive capillary electrophoresis (CE) method was developed that allows simultaneous analysis of zonisamide (ZNS), rufinamide (RFN), and lamotrigine (LMT) in pharmaceutical preparations. This study introduces the first application of CE for the simultaneous determination of ZNS, RFN, and LMT in pharmaceutical dosage forms. For the comparison a High-Performance Liquid Chromatography (HPLC) method was developed. In CE method, detection was achieved using a photodiode array detector (DAD) at a wavelength of 210 nm. A capillary with an internal diameter of 75 µm and an effective length of 40 cm was used for separation. The optimum conditions were achieved using 35 mM SDS, 6 mM borate, 10 mM phosphate buffer (pH 9.00) containing 5% isopropyl alcohol (IPA), and applying a potential of 15 kV. Under these conditions, the migration times of ZNS, RFN and LMT were observed to be 5.99 min, 6.77 min and 8.46 min, respectively. In HPLC method, detection was achieved using a photodiode array detector at a wavelength of 210 nm. A C18 column (4.6 × 100.0 mm, 3.5 µm i.d.) was used for separation, with a mobile phase consisting of acetonitrile and pH 4.0 50 mM phosphate buffer (18:82, v/v) at a flow rate of 1.0 mL min−1. In this method, the retention times of ZNS, RFN and LMT were observed to be 6.41 min, 7.29 min and 4.95 min, respectively. The validity of the developed methods was examined through parameters such as linearity, precision, accuracy, sensitivity, stability, and robustness. In CE method, the limit of detection (LOD) values for ZNS, RFN and LMT were calculated as 0.035 μg mL−1, 0.016 μg mL−1 and 0.007 μg mL−1, respectively. For HPLC method, the LOD values were determined as 0.003 μg mL−1, 0.002 μg mL−1 for RFN and 0.001 μg mL−1 for LMT. Both developed methods were successfully applied to pharmaceutical dosage forms and shown to be compliant with United States Pharmacopeia (USP 47 - NF 42). In conclusion, both methods developed in our study yielded comparable results in terms of robustness and analysis time. HPLC demonstrated higher sensitivity compared to CE and is preferred for analyses at very low concentrations, while CE is ideal for green chemistry applications due to its minimal solvent and sample consumption.
Abstract
Violanthin, a compound isolated from the stems of Dendrobium officinale, exhibits potent antioxidant and antibacterial activities. However, no research has been conducted on the identification of violanthin in mouse plasma using UPLC-MS/MS. The present study aims to develop a selective UPLC-MS/MS method for the quantification of violanthin in mouse plasma. Samples were prepared using acetonitrile for protein precipitation, with aconitine as an internal standard (IS). Chromatographic separation was achieved on a UPLC HSS T3 column with acetonitrile and 0.1% formic acid as the mobile phase. Quantification was performed in multiple reactions monitoring (MRM) mode, targeting fragment ions m/z 579.6→457.2 for violanthin and m/z 646.6→586.5 for IS. Mouse blood samples were collected at different time points following intravenous (4 mg kg−1) and oral (30 mg kg−1) administration of violanthin. The calibration plots for violanthin in mouse plasma exhibited a linear trend across the entire range of 5–2,000 ng mL−1, with both intra-day and inter-day precision RSDs below 10%. The bioavailability was determined to be 24.3%. This UPLC-MS/MS method effectively facilitated pharmacokinetic studies of violanthin in mice.
Abstract
The determination of total flavonoid content (TFC) through the aluminum chloride (AlCl3) colorimetric test utilizing spectrophotometry is commonly used as a parameter for evaluating the quality of processes as well as food and herbal medicines materials. Nonetheless, it is laborious, lengthy, and necessitates substantial amounts of chemicals. This study aims to develop and validate the dot-blot assay with AlCl3 reagent for determining TFC in plant materials. In this method, the samples were not subjected to chromatography; instead, the plates were derivatized using AlCl3 in ethanol immediately after the application of samples and evaporation the solvent. The Al(III)-flavonoid complex was scanned (421 nm) using a TLC-scanner. The validation of the method was conducted on stability, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, and robustness. The TFC of samples determined by dot-blot assay and spectrophotometry was subsequently analyzed using linear regression and Pearson correlation. The dot-blot assay for determining TFC met the stability parameter (RSD = 1.31–8.25%), intraday precision (RSD = 2.20–6.11%), inter day precision (RSD = 1.56%), linearity (r 2 = 0.9928), LOD (251.03 ng/spot), LOQ (760.71 ng/spot), accuracy (recovery = 70.81–75.61%), and robustness (RSD = 2.55 and 7.60%). There was a very strong positive linear relationship between the dot-blot assay method and spectrophotometry, with a linear regression coefficient of 0.9078 and a Pearson correlation coefficient of 0.911. The proposed method proved to be simpler, faster, and more economical for determining TFC. Thus, the method was beneficial in providing references for enhancing the quality control of food and herbal medicines.
