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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
Phellopterin, a naturally derived furanocoumarin, is widely distributed in medicinal plants like Angelica dahurica and Toddalia asiatica, as well as in citrus fruits. In this experiment, an UPLC-MS/MS bioanalytical method over the concentration range of 0.725–290 ng mL−1 was established for the quantitative analysis and pharmacokinetic study of phellopterin in rat plasma. Following protein precipitation with acetonitrile, the samples were separated by gradient elution on a UPLC system, using acetonitrile-0.1% formic acid as the mobile phase. Quantification was performed using multiple reaction monitoring (MRM) method in electrospray positive-ion mode (ESI+), with the ion transitions of m/z 301.1 → 233.4 for phellopterin and m/z 209.1 → 194.1 for the internal standard, fraxetin. The accuracy of phellopterin ranged from 87.9 to 112.4%, with the precision between 4.1 and 12.2%. The matrix effect was 92.4–97.4%, and the recovery was over 77.9%. The optimized UPLC-MS/MS bioanalytical method was successfully used to study the pharmacokinetics of phellopterin in rats. The AUC(0−t) values were 74.2 ± 7.9 ng mL−1*h for intravenous and 37.1 ± 5.3 ng mL−1*h for oral administration, while the corresponding half-lives (t1/2z) were 1.1 ± 0.2 h and 3.1 ± 0.7 h, respectively. The bioavailability of phellopterin was determined to be 16.7%.
Abstract
Berkeley rapid composting is one of the most effective ways of recovering organic waste, producing a final composting product in a very short time compared with other types of composting. For the first time in Morocco, and more specifically in Béni Mellal, this rapid composting process was applied to casing waste (50%) mixed with a manure fraction (50%) in order to study its qualitative and quantitative feasibility. The results of this experiment showed that the C/N ratio of the compost reached 21.3 and the quantitative efficiency did not exceed 47.9%. The aim of this work is to study the influence of the mixed fraction percentages and the effect of grinding the casings on the feasibility of rapid composting. The results showed that the economic efficiency of composting surpassed 60% when the casing fraction was more than 50% of the mixture and reached 65% when the casing waste was shredded.
Abstract
An analytical method based on ion-pair liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to accurately determine neomycin B in bovine edible tissues (muscle, kidney, liver, fat) and milk. The pre-treatment procedure, including protein precipitation and solid phase extraction, was investigated to extract the analytes of interest better and remove matrix interferences. After sample pre-treatment, the 1% heptafluorobutyric acid 20 μL was added to the final extract. Then, the chromatography and mass spectrometry conditions were optimized, and the established method was validated. Good linearity (r > 0.999) was obtained at five matrices. The limit of detection, and the limit of quantitation were 10 and 20 μg kg−1, respectively. Trueness and repeatability at 0.5× maximum residue limit (MRL), MRL, and 2× MRL ranged from 96.67 to 109.54% and 3.36 to 9.01%, respectively. Adding the ion-pair agent to the extracts, rather than the mobile phase, ensures that neomycin B is efficiently retained on the reverse-phase column without contaminating the ion source. This simple and sensitive LC-MS/MS method is suitable for regularly monitoring neomycin residue in bovine edible tissues and milk.
The replacement of maize with grain sorghum is a promising practice for enhancing climate change adaptation strategies in the drought-prone areas of Central Europe. The refinement of the agrotechnics of commercial hybrids contributes to the development of sustainable agriculture. A field experiment was conducted between 24 May 2023 and 27 September 2023 in Keszthely (Hungary) in order to evaluate the effects of plant density (D1 = 240,000 plants ha–1, D2 = 280,000 plants ha–1) and equidistantly increasing N doses (0–40–80–120–160–200 kg N ha–1) on the grain yield, biomass weight and leaf area index (LAI) of 4 grain sorghum cultivars (G1 = KWS Nemesis, G2 = RTG Huggo, G3 = GK Erzsébet, G4 = ES Foehn). Another aim was to examine the effect of treatments on weed coverage. According to the results, plant density and N treatment had a general significant effect on grain yield (p < 0.05), biomass weight (p < 0.05) and LAI (p < 0.05; p = 0.015), regardless of the applied cultivar. Positive correlations were observed between biological and grain yield (D1: r = 0.9, p = 0.02; D2: r = 0.91, p = 0.01) as well as between LAI and grain yield (D1: r = 0.89, p = 0.6; D2: r = 0.91, p = 0.07). Significant differences were also observed between the grain yield (p < 0.05), biomass weight (p < 0.05) and LAI (p < 0.05) of the cultivars. In general, grain yields peaked around 120 kg N ha–1 at the plant density of 240,000 plants ha–1 and around 160 kg N ha–1 at the plant density of 280,000 plants ha–1. Among the experimental conditions RTG Huggo yielded the best results. In general, weed coverage was significantly lower (p = 0.002) in denser stands. The enhancing effect of N on weed coverage could not be detected (p = 0.318). In conclusion, a plant density of 280,000 plants ha–1, a N dose of 120–160 kg N ha–1 and RTG Huggo cultivar proved to be the best under the experimental conditions.
Abstract
The BET specific area (SBET), total pore volume and micropore volume were calculated to be 1319.36 m2 g−1, 0.686 cm3 g−1, and 0.636 cm3 g−1, respectively. ZIF-67 shows a type I isotherm for N2 adsorption-desorption. The ZIF-67 have particle size 614.9 nm with zeta potential equal to 5.52 mV (neutral surface) at pH 7, which indicates possibility of hydrophobic and π-π interaction between fipronil and ZIF-67. Fipronil adsorption with ZIF-67 was found to be monolayer and favourable, as evidenced by the Langmuir adsorption isotherm and endothermic and chemisorption process, as indicated by Pseudo second order (Ps.Sec.Ord.) kinetic model. The endothermic temper of adsorption was also concluded from the value of ∆Ho and ∆S i.e. 17.19 kJ mol−1 and 0.063 kJ mol−1 K−1, respectively. The ∆Go for adsorption of fipronil were found to be −1.293, −2.749, and −3.818 kJ mol−1 for 303, 318, and 333 K, respectively. Negative value of ∆Go shows feasibility and spontaneous nature of adsorption process. Under optimised conditions, ZIF-67 achieved 68.2% maximum removal of fipronil (20 mg L−1). Results obtained from the reusability studies suggested that ZIF-67 can be recycled by washing it five times with DMF and heating at 50 °C.
Abstract
Since the last few decades, the TLC has been an essential tool in the standardization and quality control of herbal medicines. Often, the traditional Thin Layer Chromatographic (t-TLC) profiling is inadequate in separating and identifying the huge numbers of phytochemicals present therein. A simple t-TLC is unable to accommodate or separate such large numbers of spots or bands on a plate. The present investigation has tried to adopt multidimensional and multiple development methods in combination to separate 21 phytochemicals and to generate a decisive chromatographic fingerprint of the sample. The most exciting point is that the qualitative profile generated here is highly reproducible for 19 phytocompounds. The limitations of traditional TLC in separating and identifying were overcome by the present investigation. The output of the present study may be an example of creating herboprint, which is generic and conclusive in the qualitative identification of complex herbal formulations. The most significant output of this work is that the presence or absence of any herb in a polyherbal formulation can easily be detected. It generates a unique herboprint, which can be referred as an authentic chromatographic fingerprint of the complex formulation. The concept adopted here is not new in the domain of TLC, but here maximized improvisation has been imposed in the field of herbs and herbal formulations. Significantly, a concept of coordinate position(s) which has been introduced is more rational than Rf value(s) for qualitative profiling in multidimensional development.
Abstract
Despite extensive development and widespread use, existing methods for analysis of caffeine and paracetamol overlook their environmental impact. Furthermore, these methods were not developed using the Analytical Quality by Design approach, leading to a significant gap in understanding critical separation factors. Moreover, the absence of a hydrophilic interaction liquid chromatography (HILIC) method for the simultaneous analysis of caffeine and paracetamol, integrating Analytical Quality by Design and a comprehensive green approach, presents an exciting opportunity for innovation and advancement in the field. In this paper, we report an efficient and sustainable HILIC method for caffeine and paracetamol analysis, which is based on Analytical Quality by Design, green and white chemistry principles. Optimal chromatographic conditions were adjusted using an InertSil Diol column with the mobile phase of acetonitrile and ammonium acetate buffer. The method was validated according to the International Council for Harmonisation guidelines, and its applicability in the analysis of Panadol Extra® tablets was confirmed. Relative standard deviation values were 0.07–0.28% for accuracy and 0.45–0.54% for precision. The environmental footprint and effectiveness of the method were evaluated through assessments of triple-color analysis which showed the dominance of green, blue, and white with scores of 0.66, 85.0, and 83.3, respectively. These parameters confirm that the method is eco-friendly, reliable, accurate, and precise for future use in the analysis of dosage forms containing caffeine and paracetamol. This is the first time that the Analytical Quality by Design approach has been combined with green and white chemistry principles, creating a strong synergy for the development of environmentally friendly methods.
Abstract
To investigate the determination of carbamazepine, oxazepine and their metabolites 10, 11-epoxy carbamazepine (CBZ), 10, 11-dihydro10-hydroxyl carbamazepine (MHD) in blood by HPLC and their interfering factors. The samples were pretreated by protein precipitation method. The chromatographic conditions were as follows: Agilent Eclipse Plus C18 column (4.6 mm × 250 mm, 5 μm); Mobile phase: acetonitrile-water (30–70); Flow rate: 1 mL·min−1; Column temperature: 37 °C; Uv detection wavelength: 210 nm. Based on common clinical antiepileptic drugs and serum samples of high bilirubin, high lipemia and low hemolysis, the anti-interference test was established. Under the chromatographic conditions, the separation of CBE, OXC and their metabolites was good, CBZ had a good linear relationship between 0.1 and 20 mg L−1 (r = 0.9994), and CBZE had a good linear relationship between 0.05 and 10 mg L−1 (r = 0.9998); OXC has a good linear relationship in 0.05–20 mg L−1 (r = 0.9993); MHD has a good linear relationship in 0.5–50 mg L−1 (r = 0.9995). The intra-day and inter-day precision RSD<13%, and the RSD of LLOQ<19%; the stability is good, the relative recovery rate is 91.17%–118.06%, and the method validation is in line with the “Chinese Pharmacopoeia” (2020 edition). Common clinical antiepileptic drugs, hyperlipidemia, and low hemolysis serum sample matrix have no obvious interference with monitoring, but high bilirubin serum sample matrix may have interference to varying degrees. The method is sensitive, accurate, simple, rapid and economical. It can be used for blood concentration monitoring and pharmacokinetic study of CBZ, OXC and their active metabolites.
Abstract
Rosuvastatin and ezetimibe, each with distinct mechanisms of action, have a well-established use in hyperlipidemia treatment. The recent adoption of their fixed-dose combination therapy has gained significant attention due to its enhanced therapeutic efficacy in managing hyperlipidemia and improved patient convenience. However, both active pharmaceutical ingredients (APIs) face challenges related to low bioavailability and non-selective action, highlighting the need for delivery systems able to target and control their release at the site of action. To overcome these limitations, lipid-polymer hybrid nanoparticles (LPHNPs) have been developed, leveraging the combined advantages of lipid and polymer nanocarriers for improved API delivery. This study focuses on the development and validation of a simple reversed-phase high-performance liquid chromatography (RP-HPLC) method for the determination of rosuvastatin and ezetimibe in the developed LPHNPs, optimized to assess critical attributes of quality such as encapsulation efficiency (EE) and API loading capacity, which influence therapeutic outcomes.
Chromatographic separation was achieved by using a Zorbax Eclipse Plus C18 column and a mobile phase of diluted formic acid and acetonitrile (55:45, V/V) at a flow rate of 1.5 mL min−1. Detection was performed at 240 nm. The method was validated according to ICH Q2(R2) guideline, demonstrating excellent linearity, accuracy, precision and robustness.
The proposed method was used for the successful quantification of the EE and loading capacity of both APIs in LPHNPs, showing also potential for analysing their release profile by which valuable insights into their release mechanism and kinetics from the nanoparticle system could be obtained, and the stability of the designed delivery system as well, by providing effective assessment of API leakages from the LPHNPs over time, when kept at specific storage conditions.
Abstract
The preponderance of benign prostatic hyperplasia (BPH) and prostate cancer has increased in prevalence among aging men; prostate health management is becoming increasingly important. Studies indicate that substances such as beta-sitosterol and cholecalciferol may have therapeutic benefits for prostate disorders. This study aims to innovate the HPLC approach for the coexisting quantification of beta-sitosterol in Pygeum extract (Prunus africana) and cholecalciferol, providing a comprehensive strategy for evaluating the quality of herbal products targeting prostate health. The RP-HPLC technique was appraised using modified green star area (MoGSA) and BAGI metrics based on an Inertsil ODS-3 C18 column with a mobile phase of methanol and acetonitrile in a 95:5 ratio and detection at 210 nm. The strategy exhibited outstanding resolution, precision, and robustness, with a 12-min runtime. The method's linearity was confirmed with R 2 above 0.99, and the LOD and LOQ values were 0.61 μg mL−1, 0.76 μg mL−1, and 1.85 μg mL−1, 2.31 μg mL−1 for beta-sitosterol and cholecalciferol, respectively. Precision intra- and inter-day testing revealed RSD below 2%, confirming the method's reliability. Recovery studies indicated high accuracy, with recoveries of 101.50, 100.99, and 101.17, 100.92% in the pharmaceutical formulations and the supplement formulations for beta-sitosterol and cholecalciferol, respectively. This innovative dual-action approach may provide a promising therapeutic strategy by targeting multiple pathways involved in prostate function and disease prevention.
