Chromatographia最新文献

Superficially porous silica microspheres (SPSMs) with a dendritic mesoporous shell were successfully synthesized and functionalized with poly(2-(tert-butylamino)ethyl methacrylate) (PTBAEMA) brushes for application as high-performance liquid chromatography (HPLC) stationary phases. The particle size and shell morphology of the SPSMs were precisely tailored by adjusting the concentrations of tetraethyl orthosilicate (TEOS) and ammonia, as well as the TEOS addition rate. The optimized SPSM-PTBAEMA column exhibited excellent mechanical stability, as evidenced by the linear relationships observed between flow rate and column backpressure, as well as between column temperature and backpressure. Notably, the SPSM-PTBAEMA column achieved efficient separation of alkylbenzenes and polycyclic aromatic hydrocarbons (PAHs) under optimal chromatographic conditions. It demonstrated high resolution, with the chromatographic peaks of alkylbenzenes achieving resolutions between 1.5 and 5. Additionally, the column exhibited efficiency up to 59,100 plates/m for 1-phenylhexane and 64,610 plates/m for chrysene. These findings highlight the column’s superior performance in reverse-phase separations, offering excellent selectivity and stability across a diverse range of hydrophobic compounds. Overall, the study confirms the potential of SPSM-PTBAEMA as a highly effective stationary phase for HPLC, delivering robust and reliable performance in the separation of complex hydrophobic analytes.

The N-nitroso-vildagliptin impurity has been classified as genotoxic. According to the EMA, this impurity must be controlled within a limit of 15 ppm in the vildagliptin drug substance. This work demonstrates the synthesis and characterization of the N-nitroso-vildagliptin impurity using IR, NMR, and LC–MS techniques. The synthesized N-nitroso-vildagliptin impurity was used as a reference standard for the development and validation of an LC–MS/MS method, achieving a limit of detection (LOD) of 0.44 ppm and a limit of quantification (LOQ) of 1.46 ppm.

A robust and environmentally sustainable LC–MS method was developed and optimized using a Box–Behnken Design (BBD) to simultaneously quantify montelukast, etofylline, and theophylline in synthetic plasma and marketed formulations. Design-Expert software (version 13.0) facilitated a systematic exploration of three critical chromatographic variables—methanol concentration, flow rate, and mobile phase pH—across three coded levels, with their effects assessed on retention time (RT) and tailing factor (TF). Response surface methodology and statistical analyses (ANOVA) confirmed model significance and predictive reliability, with second-order polynomial equations describing variable-response relationships. The optimized conditions (78.13% methanol, 1.0 mL/min flow rate, pH 4.4) yielded reproducible retention and peak symmetry, with < 5% deviation between predicted and experimental values. Mass spectrometry analysis employed a triple quadrupole instrument in positive ESI mode with SRM transitions: m/z 593.27 (montelukast), m/z 224.22 (etofylline), and m/z 180.164 (theophylline). The validated method met all regulatory criteria per EC guidelines, with excellent linearity (R² > 0.999), precision (%CV < 15%), and recovery (99–100.46%). Stability studies demonstrated analyte robustness under various storage conditions. Notably, method greenness was evaluated using Analytical GREEnness (AGREE), ComplexGAPI, Eco-Scale tools and Blue Applicability Grade Index (BAGI), confirming a low environmental footprint due to minimal solvent consumption, non-toxic reagents, and efficient runtime. In addition, the method was successfully applied to quantify analytes in commercial tablet formulation, confirming accuracy, selectivity, and absence of interference. This study not only establishes a highly sensitive, precise, and green LC–MS platform for multi-analyte quantification in biological matrices but also extends its applicability to quality control in marketed products.

Accurate values of the specific refractive index increment (∂n/∂c) are essential to the accurate determination of molar mass averages, distributions, and related macromolecular parameters by, among others, size-based separations with online static light scattering and differential refractive index (DRI) detection. Examined here is the 100% mass recovery method of calculating the ∂n/∂c of dilute macromolecular solutions, when employing mixed solvents in a size-based separation (e.g., size-exclusion chromatography or SEC) with DRI detection. This method has been used successfully in the past for determining the ∂n/∂c of various polyelectrolytes. It is quicker, generally simpler, and less sample-intensive than its offline, batch-mode DRI counterpart. Whether or not the 100% mass recovery method allows for the necessary solvent equilibration within the immediate vicinity of the polymer chain during a chromatographic run, so as to allow for accurate determination of ∂n/∂c in SEC/DRI experiments, is evaluated here. This is done using a set of three narrow-dispersity linear polystyrene standards covering a 40-fold range in molar mass, dissolved in a 25:75 mix of tetrahydrofuran and N,N-dimethyl formamide. Results are compared to those previously obtained by the batch-mode method and from calculations involving the accurately known molar masses of the polymers and refractive indices of the solvents. The 100% mass recovery method of obtaining ∂n/∂c values, while of great help for determining the ∂n/∂c of, e.g., polyelectrolytes, does not appear able to overcome the obstacle of preferential solvation when analyzing macromolecules in a mix of non-isorefractive solvents with dissimilar second virial coefficients.

Aim

This study aimed to develop and validate a chromatography-based analytical method for the quantification of Vonoprazan fumarate in pharmaceutical formulations, minimizing solvent consumption. A single chromatographic condition was optimized using the principles of design of experiments (DoE) and an analytical quality by design (QbD) approach, in compliance with regulatory guidelines.

Methods

The method was validated per ICH guidelines, assessing linearity, system suitability, accuracy, precision, robustness, specificity, solution stability, and filter compatibility. Box–Behnken response surface methodology was employed to optimize critical method parameters (CMPs) based on the analytical target profile. Green analytical tools, including the Green Analytical Procedure Index (GAPI), National Environmental Method Index (NEMI), Analytical GREEnness Metric (AGREE), and Analytical Eco-Scale (AES), were applied to evaluate environmental impact.

Results

The method exhibited excellent linearity (R² = 0.9999) within a working concentration range of 7.5–22.5 µg mL⁻¹. Recovery studies at 50–150% concentrations demonstrated 99–101% accuracy. The assay of Vonoprazan yielded 100.6%, with a retention time of 1.825 min. Intra- and inter-day precision showed relative standard deviations below 2%. Robustness studies confirmed method stability under varied conditions. The Box–Behnken design demonstrated a significant quadratic relationship between CMPs and critical material attributes (CMAs).

Conclusion

The developed HPLC method provides accurate, precise, and specific quantification of Vonoprazan in bulk and formulations. Its excellent recovery, minimal standard deviation, and eco-friendly profile make it suitable for routine pharmaceutical analysis, confirming its reliability and sustainability.

Graphical Abstract

A simple and efficient strategy was developed for the identification of material devices’ polymers and the extraction of the additives contained within. In this study, the focus is put on the presence of phthalate esters in French medical devices, mainly on diethylhexyl phthalate (DEHP), being reported as toxic, endocrine disruptor plasticisers. Their presence was investigated across seven standard medical devices, especially concerning newborn exposure, and compared with results obtained in similar materials from the past decades. Only traces of DEHP, below the limit of quantification (< 6 ppm) were detected in one of the samples by GC–MS using a standard for identification and quantification. This study shows that phthalates’ presence in medical devices used in French hospitals has been greatly diminished, to the benefit of healthier hospital environments.

Aconitum alkaloid poisoning which can lead to malignant arrhythmia, cardiogenic shock and even death has been frequently reported due to improper intake of Aconitum species in hospital emergency rooms. In this study, a simple method for simultaneous determination of 14 aconitum alkaloids in human blood and urine by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) was developed. Blood and urine samples were purified by supported liquid extraction (SLE) and analyzed by UPLC-MS/MS. Good linear relationships for 14 aconitum alkaloids were obtained in the corresponding range of 0.1–50 ng mL⁻¹ with correlation coefficients greater than 0.999 and detection limits of between 0.002 and 0.019 ng mL⁻¹. The average recoveries measured at three concentration levels ranged from 80.0% to 110.1% and 85.0% to 110.2% in spiked blood samples and urine samples, respectively, with the relative deviation less than 10%. The blood matrix effects ranged from 88.3% to 109.8%, while the urine matrix effects ranged between 91.4% and 103.6%. Both the intra-day and inter-day precisions were less than 11%. Finally, the method was successfully applied to the determination of aconitum alkaloids in the blood and urine of clinic poisoned patients showing its good potential for poison diagnosis in clinical emergency cases.

In this study, silanized cardboard samples (HSi-CB, MeSi-CB, EtSi-CB, and PrSi-CB) were prepared by reacting bare cardboard with ethoxysilane/chlorosilanes bearing different substituents (H-, CH₃-, CH₃CH₂-, and CH₃CH₂CH₂-) in toluene. Characterization using FTIR spectroscopy, elemental analysis, and surface area/pore volume measurements confirmed successful silanization, with HSi-CB exhibiting the largest amount of grafted silanes and branched polymeric/oligomeric siloxane networks. However, inverse gas chromatography (IGC) revealed that MeSi-CB exhibited the highest adsorption affinity toward hydrocarbons due to its larger dispersive surface energy (left( {mathop gamma nolimits_{{text{S}}}^{{text{D}}} } right)) , resulting from grafted methylsilane groups, reduced hydroxyl groups, and the formation of micropores and channels via siloxane condensation. In contrast, EtSi-CB and PrSi-CB displayed lower (mathop gamma nolimits_{{text{S}}}^{{text{D}}}) values due to the grafting of fewer silane groups and the limited formation of branched siloxane networks. Although HSi-CB exhibited the highest amount of silanes, its (gamma_{{text{s}}}^{{text{D}}}) values remained comparable to those of bare cardboard. These results underscore the critical role of surface dispersive components and micropore/channel formation in boosting the adsorption performance of silanized cardboard. These results also provide valuable insights for the development of more efficient adsorbents for hydrocarbon capture and separation applications.

A straightforward and precise technique for the analysis of Rose Bengal concentrations in canine plasma was established and validated using HPLC. Following a simple protein precipitation method with methanol, separation occurred on an XBridge Phenyl column with a mobile phase of 10 mM ammonium phosphate and acetonitrile (65:35, v/v). Rose Bengal and meloxicam, the internal standard, were confirmed by monitoring UV–visible wavelengths at 549 nm and 370 nm, respectively. The lower limit of quantification (LLOQ) was determined to be 25 ng mL⁻¹ in a 100 μL sample. The recovery was greater than 90% while intra-assay variability was less than 5%. Inter-assay variability was less than 7%. This method could be useful in pharmacokinetic studies.

Parkinson’s disease is a progressive neurodegenerative disorder with an increasing global prevalence, necessitating advanced therapeutic and analytical approaches. Puerarin, a phytoconstituent from Pueraria lobata (Kudzu), has therapeutic potential in respiratory illnesses, neurological diseases, psoriasis, and viral infections. However, puerarin quantification remains challenging due to complex methods, prolonged retention times, and missing stability-indicating degradation studies in published data. This study develops a simple, reliable, rapid, and cost-effective reverse-phase high-performance liquid chromatography method for quantifying puerarin in marketed and nanoformulations. A central composite design enabled statistical optimization, fewer experimental runs, and critical analytical attributes. The method was validated as per ICH (Q2R1) guidelines. Chromatographic conditions included an acetic acid buffer (0.1%, pH 3.2):methanol (50:50, v/v) mobile phase, a 1 mL min⁻¹ flow rate and a 250 nm detection wavelength, achieving a puerarin retention time of 3.1 min. The linear calibration curve (R² > 0.999) had LOD and LOQ values of 0.2148 µg mL⁻¹ and 0.6511 µg mL⁻¹, respectively. Precision studies (intra-day and inter-day) showed an RSD below 2% with consistent recovery. The method quantified puerarin in marketed and nanoformulations with 102.29% and 98.84% efficiency. Stress degradation studies confirmed robustness. The developed method provides a reasonably lower retention time and its validation produces quality data compared with publications resembling a problem-solving approach for quantifying puerarin. This validated method provides an accurate, precise, and economical strategy for puerarin quantification in pharmaceuticals.