Journal of chromatographic science最新文献

Nowadays, there is a strong interest in the scientific community in developing innovative methodologies within a green analytical chemistry framework. Herein, we introduce the first chromatographic approaches for the concurrent estimation of paracetamol (PAR), carbinoxamine (CRX), and pseudoephedrine (PSE) intended to relieve COVID-19 and common cold symptoms. The first method was thin layer chromatography (TLC) densitometry, which depends on the separation of the studied medications on TLC silica gel plates using ethyl acetate: methanol: ammonia (7.0: 3.0: 0.2, by volume) as the developing system, and were scanned at 208.0 nm. The data were linear in the ranges of 1-25 μg/band for PAR, 1-25 μg/band for PSE and 0.1-5 μg/band for CRX. The second method was reversed-phase high-performance liquid chromatography separation on a Kromasil C18 column using a mixture of 0.01 M phosphate buffer containing 0.1% triethylamine (pH 3.5) adjusted with orthophosphoric acid and ethanol at a flow rate of 1.0 mL/min in a gradient program. The separated peaks were detected at 215.0 nm over a concentration range of 10-250 μg/mL for PAR, 5-35 μg/mL for PSE, and 0.5-25 μg/mL for CRX. Both approaches were validated according to International Conference on Harmonization (ICH) guidelines. Finally, the impact of these methods on the environment was evaluated by many tools.

Novel C18-functionalized magnetic nanomaterials; i.e., C18@poly-styrene-divinylbenzene-glycidyl methacrylate-Fe3O4 (C18@PS-DVB-GMA-Fe3O4) have been synthesized by using N, N-dimethyloctadecylamine as modifying agent, which could be beneficial to remove the blood phospholipids. The C18@PS-DVB-GMA-Fe3O4 nanoparticles have been used and evaluated in the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) procedure for human plasma prior to the analysis of propofol by supercritical fluid chromatography (SFC). In the QuEChERS procedure, human plasma samples are directly mixed with extraction solvent and C18@PS-DVB-GMA-Fe3O4 nanoparticles, and the extraction and cleanup procedures have been accomplished simultaneously. The SFC separation was performed with a C18 column (Thermo Scientific™ Acclaim™ 120, 250 × 4. 6 mm, 5 μm) within 5 min, using thymol as the internal standard. Supercritical carbon dioxide was used as the mobile phase with methanol as the cosolvent at the flow rate of 1.0 mL/min. The column temperature was 38°C, and detection wavelength was 275 nm. A good linearity was obtained among the propofol concentration range of 0.5-10 mg/L (R2 = 0.9997) with the limit of detection of 0.17 mg/L. Recoveries were in the range of 76.5-91.9%, with RSD less than 7.9%. These results suggested that method is convenient, rapid with high accuracy and little matrix effect, and suitable for rapid determination of propofol plasma concentration.

Huangxueyishen decoction (HXYS) is proven effective in treating chronic renal failure in clinical practice. The study aims to identify and analyze the chemical constituents of HXYS decoction, and to quantitatively analyze and perform the study of the pharmacokinetics of its main active ingredients. The Ultra-Performance Liquid Chromatography-Linear Trap Quadrupole-Orbitrap Mass Spectrometry (UPLC-LTQ-Orbitrap-MS) system was used to qualitatively analyze the main components of HXYS. Among these compounds, UPLC-QTRAP-MS/MS was applied to further perform the simultaneous quantification of selected important constituents, and pharmacokinetic studies were performed on eight blood-entry components. A total of 87 compounds were tentatively identified, including 26 flavonoids and flavonoid glycosides, 9 phthalides, 9 phenylpropanoids, 9 lignans and 30 other compounds. Two rapid, sensitive and reliable UPLC-MS/MS method have been successfully developed for the simultaneous determination of 11 constituents and 8 components in the plasma of rats at different time points after HXYS administration. Tmax of the eight components was 0.88-4.00 h, t1/2 was 0.65 ~ 4.58 h and AUC(0-∞) ranged from 145.88 ~ 1785.63 μg·h/L. In this study, the chemical components of HXYS were comprehensively characterized, and the active components were further screened in combination with network pharmacology, which predicted and verified the chemical material basis of HXYS and laid the foundation for analyzing its bioactive substances.

A Stability indicating revered phase high performance liquid chromatography (RP-HPLC) method have been developed and validated for the estimation of Mifepristone. LC-MS Studies was carried out for identification of possible degradation products. A simple, rapid, accurate and precise stability indicating RP-HPLC method was developed for quantification of Mifepristone. The developed method used the mixture of methanol and water (88:12 v/v) as mobile phase at flow rate of 1 ml /min, which was optimized with the help of Quality by Design approach. Detection was carried out at 305 mm. The linearity of the proposed method was found in the concentration range of 5-25 μg/ml with regression coefficient (R2) of 0.996. LOD and LOQ were found to be 0.0324 and 0.0982 μg/ml, respectively. The recovery of the proposed method was found to be 98%-100%. The method was found to be precise and robust. The developed stability indicating RP-HPLC method was successfully applied for quantification of Mifepristone in pharmaceutical dosage form. The degradation products were characterized by LC-MS and the fragmentation pathways were proposed.

San-Huang-Xie-Xin-Tang (SHXXT), a traditional Chinese medicine formula composed of Coptidis rhizome (CR), Scutellariae radix (SR) and Rhei rhizome (RR), is widely used to treat hypertension, gastritis and peptic ulcer clinically. However, the chemical constituent of SHXXT is still unclear due to its complexity, which hindered the discovery of effective compounds and quality control. Thus, an in-depth understanding of its chemical constituents is very essential. To address this problem, comprehensive analysis of chemical constituents of SHXXT was performed by high performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS/MS). As a result, 45 compounds were identified, including 8 phenolic acids, 15 flavonoids, 13 alkaloids, 8 anthraquinones and 1 lignan. Among them, 17 compounds were from CR, 17 compounds were from SR and 11 compounds were from RR. This established method can systematically and rapidly analyze the chemical constituents in SHXXT, which provides chemical foundation for further research on effective substances and action mechanism of SHXXT.

Residual solvent analysis is a common method used in the manufacturing of finished goods and pharmaceuticals to ensure the safety of the final product to the consumer. Typically, this involves a headspace sample introduction set up and then separation by gas chromatography (GC) with detection by a flame ionization detector (FID). This analysis can be very time consuming in sample preparation, calibration and analysis time. A full evaporative technique has been applied to both solid and liquid samples for the rapid vaporization of the solvent analytes, which is then introduced to a GC for separation. Additionally, a methanizer was used in line with the FID creating a uniform response for solvents of various heteroatoms and functionalities. This combination of full evaporative technique with a methanized-FID allows for the use of a single response factor for residual solvent analysis with demonstrated repeatability of ˂4%RSD. Spiked solid sample analysis shows recovery between 95% and 105% of solvents tested at ⁓2 μg of each analyte. Overall, the combination of full evaporative headspace sampling and methanized-FID can be applied to any sample matrix for any solvent used in manufacturing or production, making a universal method for residual solvent analysis.

Medicines used in ayurveda are typically made of many herbs or are polyherbals. Standardization of these medicines can be carried out by quantitative estimation of two or more of its markers simultaneously. Berberine and ursolic acid are two active markers which are present in an Ayurvedic formulation, Giloy Tulsi tablets. In the present research work, the Reverse Phase High Performance Liquid Chromatography (RP-HPLC) method was developed and validated for the simultaneous quantitative determination of berberine and ursolic acid from the formulation. With an RP Hemochrom C18 column, chromatographic separation was accomplished at 292 nm with eluent composed of methanol: acetonitrile (4:1, v/v) at a flow rate of 1.0 mL/min. The retention time of berberine and ursolic acid was obtained to be 1.5 ± 0.02 and 3.2 ± 0.02 min, respectively. A simple, rapid, accurate, specific, and robust analytical method was developed to estimate berberine and ursolic acid. This validated method can be used for routine quality control of ayurvedic formulations or herbal formulations having plants which contain berberine and ursolic acid.

Two enantiomeric novel chiral stationary phases (CSPs) R-3-Amide-BINOL CSP (CSP-1) and S-3-Amide-BINOL CSP (CSP-2) were prepared using (R/S)-1,1'-bi-2-naphthol (BINOL) derivatives as chiral selectors. The structure of CSPs was characterized by nuclear magnetic resonance, scanning electron microscope and elemental analysis. Four chiral solutes were selected under normal phase HPLC conditions to evaluate the chiral separation ability of the two novel CSPs. The effects of mobile phase and acidic additives on enantiomeric separation were investigated. The combination of molecular docking simulation and experimental data has elucidated the crucial role of hydrogen bonds and π-π interactions formed between the analyte and CSP in chiral recognition, and different configurations of CSP can cause enantiomeric elution sequence reversal, indicating that the configuration of chiral selectors in CSP has a significant impact on chiral recognition ability.

Ayurveda describes purification process of certain herbal drugs to reduce the toxicity and make them suitable for therapeutic purpose. The objective of the study was to evaluate the effect of detoxification process on plumbagin (PG) from the Plumbago zeylanica L. roots in marketed samples. It involved procurement of market samples from five states of India viz. Andhra Pradesh, Gujarat, Maharashtra, Madhya Pradesh and Punjab. The roots were purified in lime water (LW) as mentioned in Ayurveda. Reverse Phase Ultra-Flow Liquid Chromatography method was validated for identification of PG in unprocessed and processed roots and in the media (LW) used for purification after processing. The data was statistically analyzed by Analysis of Variance (ANOVA) and tested for significance by the Dunnett multiple comparison test. Results were expressed as mean ± SD mg/g dry weight of extract. The study indicated that the PG was reduced quantitatively after processing, while the amount of PG found in the LW was observed to be increased, indicating the leaching of PG during the purification process. In conclusion, the detoxification process eliminates PG from its roots and discloses the leaching effect in the media for the first time.

Dapagliflozin (DAPA), an inhibitor of sodium-dependent glucose cotransporter-2, has been created to treat individuals with type 2 diabetes mellitus. A method was developed and validated using high-performance liquid chromatography coupled to tandem mass spectrometry to aid in studying the connection between clinical effectiveness and concentration of DAPA and its primary metabolite dapagliflozin 3-O-glucuronide (D3OG) in human plasma. The two analytes were separated using the Waters XSELECT HSS T3 (2.1 × 100 mm, 3.5 μm; Waters Co., Milford, USA) chromatographic column, with a mobile phase flow rate of 0.3 mL/min. The elution program was performed after protein precipitation with methanol, which only required a 5-min duration. The extraction recovery was from 99.8 to 109% for DAPA and from 101 to 103% for D3OG. Validation of the method for detecting DAPA within the range of 5-50 ng/mL and D3OG within the range of 50-500 ng/mL demonstrated satisfactory inter- and intra-day precision and accuracy. The method was successfully developed and validated, and it was used to measure the levels of DAPA and D3OG in plasma samples from patients with type 2 diabetes mellitus.