Biomedical Chromatography最新文献

Sibutramine (SBT) is a synthetic anorectic agent formerly prescribed for obesity but withdrawn due to cardiovascular risks. Its illicit addition to herbal weight-loss products remains a major health concern. This study reports the development and validation of a green, rapid, and sensitive HPLC-PDA method for SBT quantification in herbal teas. Separation was performed on a C18 reversed-phase column (150 × 4.6 mm, 5 μm) using ethanol:water (35:65, v/v) acidified to pH 3.0 with orthophosphoric acid, under isocratic conditions (2.0 mL/min, 40°C, 10-min runtime). A matrix-matched calibration strategy was employed to minimize matrix effects. The method showed excellent linearity (R² = 0.9987) within 1.00–30.00 μg mL⁻¹, with LOD and LOQ of 0.06 and 0.20 μg mL⁻¹. The validation of the method, rigorously conducted in accordance with the ICH Q2(R2) guidelines, unequivocally confirmed its high accuracy, reproducibility, and robustness across multiple experimental conditions. Comprehensive multi-metric assessments further demonstrated the method's outstanding analytical performance, remarkable applicability, and notable environmental sustainability. Taken together, these results underscore that the method is not only highly reliable and precise but also eco-conscious, making it exceptionally well suited for routine screening and monitoring of complex herbal matrices, fully aligning with the principles of white analytical chemistry.

Podophyllotoxin, a naturally occurring cyclolignan isolated from the root and rhizomes of Podophyllum species is mainly used to synthesise etoposide and teniposide, which are used in various diseases. The present work proposes a simple, sensitive, specific, and rapid method to quantify podophyllotoxin using high-performance thin-layer chromatography (HPTLC). Podophyllotoxin was quantified in the roots and rhizomes of Podophyllum hexandrum, isolated podophyllotoxin and marketed mother tincture. A precise and validated densitometric method (R_f 0.41) was developed after resolving it on a silica gel plate using toluene:acetone:formic acid (6.5:5.6:1.4 v/v/v) as the mobile phase. The developed method was validated by linearity, accuracy, precision, range, limit of detection, limit of quantification, specificity and robustness. For podophyllotoxin, there was a linear relationship between standard solution concentration and peak response (area) in the 200–1000 ng spot⁻¹ range. The interday precision of podophyllotoxin ranged from 194.26 ± 9.302 to 314.06 ± 4.15, with a %RSD of 4.7–1.3. Similarly, the intraday precision ranged from 214.7 ± 19.55 to 443.6 ± 35.84, with a %RSD of 3.5–5.9. The chromatographic results suggest that the developed method can be used for the comparative identification of podophyllotoxin in the ethanolic extract, isolated podophyllotoxin and marketed mother tincture.

Tafenoquine, an 8-aminoquinoline antimalarial, represents a promising advancement in combating malaria, but its bitter taste and lack of paediatric formulations hinder effective treatment for children. In response, we have formulated a chocolate-based chewable tafenoquine tablet for paediatric use. A rapid, stability-indicating high-performance liquid chromatography method with ultraviolet detection was developed and validated for tafenoquine succinate quantification. Tablet samples were extracted with 85% methanol and analysed on a Waters XBridge C18 (150 × 4.6 mm, 5 μm) column using an isocratic mobile phase of 50 mM potassium dihydrogen orthophosphate buffer (pH 4.5) and acetonitrile (40:60, v/v). Detection was at 254 nm, with a retention time of 4.3 min. The method was linear over 0–313.6 μg/mL (R² ≥ 0.999) with limits of detection and quantification of 2.22 and 6.73 μg/mL, respectively. Precision (RSD 0.15%–1.35%) and accuracy (101.48%–101.90%) met International Council for Harmonisation Q2 (R2) criteria. Forced degradation showed tafenoquine's susceptibility to acidic (29.33%), basic (18.83%), photolytic (complete degradation by day 14), and oxidative (8.33%) stress, with complete chromatographic separation from degradation products. This robust, rapid and low-cost assay is suitable for routine content and stability testing, is adaptable to other tafenoquine formulations and can be further applied to clinical settings.

Preeclampsia (PE) is a severe hypertensive disorder of pregnancy involving complex metabolic disturbances. This study aimed to elucidate PE's pathogenesis and aspirin's preventive mechanism using metabolomics and network pharmacology. The untargeted urinary metabolomics via ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) were performed on healthy pregnant women (n = 11), PE patients (n = 9), and potential PE patients with aspirin intervention (n = 12). Multivariate analysis identified 162 differential metabolites. The PE group exhibited a distinct metabolic profile characterized by dysregulation in tryptophan, purine, arachidonic acid, and quinone pathways, contributing to increased oxidative stress, vasoconstriction, platelet aggregation, and inflammation. Notably, aspirin intervention reversed the levels of 28 key metabolites. Its primary preventive mechanism was associated with the targeted modulation of tryptophan metabolism and one-carbon pool by folate, which appeared to inhibit the serotonin synthesis pathway and improve endothelial function. Importantly, both metabolomics and network pharmacology identified the one-carbon metabolic and tryptophan metabolism pathways as key preventive targets for PE, corroborating their role in aspirin's mechanism. In conclusion, this study revealed a “metabolic network imbalance” in PE and confirmed that aspirin conferred specific protection to metabolism. These findings offered new insights for multitarget prevention strategies for PE and the development of diagnostic systems for metabolic biomarkers.

Flibanserin is the initial pharmaceutical treatment for hypoactive sexual desire disorder (HSDD). The analysis of urine samples plays a crucial role in the quantitation of flibanserin since a portion of flibanserin is excreted unchanged in the urine. An analytical method was proposed to quantify flibanserin in artificial urine samples (as model matrices). The integration of the spray-assisted fine droplet formation-liquid phase microextraction (SFDF-LPME) method and gas chromatography–mass spectrometry (GC–MS) system was performed for the first time to improve the sensitivity of the GC–MS system for flibanserin. Several parameters, including spraying cycle, extraction solvent type, mixing type and period, and sample volume, were systematically optimized to enhance the signal-to-noise ratio (S/N) of the analyte. After determining the optimal conditions, the analytical performance measurements of the system were figured out. The limit of detection (LOD), the limit of quantification (LOQ), and coefficient of determination (R²) values were 6.91, 23.05 μg kg⁻¹, and 0.9989, respectively. Recovery experiments were performed in artificial urine samples within the specified linear working range of 33.15–505.66 μg kg⁻¹. The SFDF–LPME–GC–MS method was efficiently applied to artificial urine samples by computing the matrix-matching calibration strategy, with percentage recovery values ranging from 90.0% to 105.9%.

Parkinson's disease (PD) is a progressive neurodegenerative disorder marked by the loss of dopaminergic neurons in the substantia nigra and the pathological accumulation of α-synuclein (α-Syn). Rotenone, a mitochondrial complex I inhibitor, reliably reproduces these hallmark features and is therefore widely used to establish experimental PD models. Shiliuwei Kangchanzhijing capsules (SLW-KCZJ capsules), a traditional Chinese medicine (TCM) formulation comprising 16 herbal components, were specifically developed for PD management. This study systematically evaluated the neuroprotective effects and underlying mechanisms of SLW-KCZJ in a rotenone-induced PD mouse model. SLW-KCZJ treatment significantly improved movement distance and balance–coordination, attenuated neuronal loss in the substantia nigra, and markedly suppressed neuroinflammatory responses. At the molecular level, the capsules increased tyrosine hydroxylase expression by approximately 200% and elevated Parkin and protein phosphatase 2A levels by approximately 60% and 80%, respectively. In contrast, they robustly inhibited polo-like kinase 2 expression and reduced α-Syn levels by approximately 60% and 40%. The intervention also increased striatal dopamine (DA) and homovanillic acid levels while lowering neurofilament light chain and oligomeric α-Syn. In summary, this study provides the first evidence that SLW-KCZJ capsules exert neuroprotective effects by modulating the Parkin/PP2A/α-Syn signaling pathway, offering a promising TCM-based therapeutic strategy for PD.

Selpercatinib (SPB) is a selective RET kinase inhibitor used to treat non–small cell lung cancer and thyroid cancer. Separation and identification of impurities formed during the manufacturing or storage of drug substances play a key role in determining their stability under various conditions during the life cycle of the drug. Hence, in the present study, SPB was exposed to different stress conditions like hydrolytic (acid, base and neutral), oxidative, thermal and photolytic stress conditions. A total of five degradation products were formed under the specified conditions. A UHPLC-PDA method employing Agilent Zorbax Extend C18 RRHD (100 × 2.1 mm, 1.8 μm) column with mobile phases of 0.1% formic acid in H₂O (A) and 0.1% formic acid in MeOH: ACN (70:30 v/v) (B) in gradient elution at a flow rate of 0.3 mL/min was developed to separate the potential degradation products. LC-QToF-MS/MS was used for the structural characterisation of the impurities. One of the degradation products (DP-2) was isolated and characterised through 1D and 2D NMR experiments. The developed method was validated as per ICH Q2 (R2) guidelines and provides valuable information about the stability of SPB, which can offer a strong foundation for its formulation development, quality control and regulatory compliance in bulk drug and dosage forms.

Diabetes mellitus is a global health burden, necessitating effective combination therapies. The fixed-dose formulation of sitagliptin phosphate (SGP, 100 mg) and lobeglitazone sulfate (LGS, 0.5 mg) offers synergistic benefits by enhancing insulin sensitivity and glucose-dependent insulin secretion. However, simultaneous quantification remains challenging due to their dosage disparity and the narrow therapeutic index of LGS. This study reports a validated, stability-indicating RP-HPLC method for concurrent estimation of SGP and LGS in a synthetic mixture. Separation was achieved on a Pursuit 5 Diphenyl column (150 × 4.6 mm, 5 μm) using a gradient of 0.1% formic acid and acetonitrile at 1.0 mL/min, with PDA detection at 254 nm. The method complied with ICH Q2(R2) guidelines, showing specificity, linearity, accuracy, precision, and robustness. Forced degradation studies revealed marked instability of SGP under acidic and alkaline conditions, whereas LGS remained stable. LC-MS/MS analysis identified a major degradation product at m/z 234, and probable fragmentation pathways were proposed. In silico ADMET and toxicity profiling predicted high gastrointestinal absorption for all degradation products, with PI-1 and PI-2 flagged for carcinogenicity and all except PI-3 showing nephrotoxicity. This integrated analytical–computational approach provides a reliable tool for quality control and safety assessment of this antidiabetic formulation.

Enasidenib (ESD), an oral medication, was used for the treatment of patients with refractory or relapsed Acute Myeloid Leukemia. No prior UPLC-MS/MS method with combined green metrics and in silico metabolism analysis for ESD was reported, so the research sought to establish an ultrafast UPLC-MS/MS method for estimating ESD in the HLMs matrix. The MS/MS analysis was applied applying positive ESI ionization mode, and chromatography using an Eclipse Plus C8 column (reversed phase) within one minute. The UPLC-MS/MS method exhibited a good degree of greenness as approved by the MoGAPI score (68.0) and the AGREE score (0.66). The linearity range was form 1 ng/mL (LOQ) to 4000 ng/mL. The precision and accuracy for intraday and interday measurements varied from −3.11% to 10.67% and −7.22% to 12.33%, respectively. The in vitro t_1/2 and the intrinsic clearance (Cl_int) were determined to be 82.52 min (long) and 9.83 mL/min/kg (low), respectively that is considered a low clearance drug. Slight structural modifications to the 2-methyl propan-2-ol moiety and pyridine ring in drug design could upsurge the ESD metabolic stability. The combined in vitro/in silico method delivers a resource-efficient strategy for early-stage metabolic screening and progressing innovative drug research focused on improving metabolic stability.