Journal of Chromatography A最新文献

Food safety problem caused by aflatoxins (AFs) has become a major concern worldwide. However, due to the complexity of food matrices and the low concentration of analytes, the accurate and sensitive determination of AFs and their precursors in the biosynthetic pathway is extremely challenging, so the development of efficient sample preparation techniques has been urgently required. This paper reviews the recent advances in sample preparation based on some emerging extraction media for the determination of AFs and their precursors in different food samples, including ionic liquids (ILs) and IL-based composites, metal-organic frameworks (MOFs) and covalent organic frameworks (COFs). These extraction media can be combined with different sample preparation techniques, such as dispersive liquid-liquid microextraction, solid-phase extraction, and magnetic/dispersive solid-phase extraction, mainly depending on their physicochemical properties. They exhibit efficient extraction and enrichment performance towards AFs and their precursors, which is attributed to their multiple-interaction mechanism and/or porous structure. This review also presents the current challenges and future prospects of these emerging extraction media for sample preparation of AFs and their precursors from food.

Significant progress has been made in the last two decades in producing small (<2μm), high-purity, and low-adsorption particles, columns and system hardware, for ultra-high pressure liquid chromatography (UHPLC). Simultaneously, the recent rapid expansion of cell and gene therapies for treating diseases necessitates novel analytical technologies for analyzing large (>2 kbp) plasmid double-stranded (ds) DNA (which encodes for the in vitro transcription (IVT) of single-stranded (ss) mRNA therapeutics) and dsRNAs (related to IVT production impurities) biopolymers. In this context, slalom chromatography (SC), a retention mode co-discovered in 1988, is being revitalized using the most advanced column technologies for improved determination of the critical quality attributes (CQAs) of such new therapeutics. In this review, we first recall non-exhaustively the main currently available analytical techniques (enzyme-linked immunosorbent assay (ELISA), agarose gel electrophoresis (AGE), pulse field gel electrophoresis (PFGE), capillary gel electrophoresis (CGE), mass photometry (MP), anion-exchange chromatography (AEX), ion-pairing reversed-phase liquid chromatography (IP-RPLC), hydrophobic interaction chromatography (HIC), size-exclusion chromatography (SEC), hydrodynamic chromatography (HDC), highly converging flow ultra-filtration (HCF-UF), asymmetrical flow field-flow fractionation (AF4), mass spectrometry (MS), and atomic force microscopy (AFM)) for analyzing mixtures containing large nucleic acid biopolymers, while assessing their strengths and weaknesses. We then focus comprehensively on the SC technique, report on its past applications since its birth, and review in detail the history and evolution of the proposed retention mechanisms accounting for the observations made in SC. This includes and emphasizes the latest physico-chemical insights (shear rates in packed HPLC columns, entropic elasticity and relaxation of dsDNA, dsRNA, and mRNA biopolymers) governing the retention behavior of such biopolymers in SC. Finally, based on the recent advancements in understanding the fundamentals of retention in SC, we provide some perspectives and recent proof-of-concept for the analytical characterization by SC of large dsDNAs (plasmid digests, polymerase chain reaction (PCR) verification), the separation of supercoiled/circular and linear dsDNAs (plasmid linearization), the isolation and quantification of large dsRNAs impurities present in mRNA samples produced by IVT, and the differentiation between dsRNA conformers.

Two-dimensional liquid chromatography (2D-LC) separation systems, based on two independent columns with different separation mechanisms, have exhibited strong resolving power for complex samples. Therefore, in recent years, the exceptional resolution of 2D-LC has significantly advanced the chemical separation of natural products, such as complex herbs, greatly facilitating their qualitative and quantitative analysis. This paper aims to review the latest strategies of 2D-LC in the quantitative analysis of complex chemical compositions in natural products. To this end, the major advantages and disadvantages of various column couplings in 2D-LC are discussed based on specific studies, along with suggested solutions to address the identified drawbacks. Moreover, the applications of different detectors combined with the latest chemometrics in 2D-LC for accurate quantitative analysis of natural products are reviewed and discussed.

Evodiamine, a chiral quinazoline alkaloid in the traditional Chinese medicine Evodiae fructus, exhibited efficacy for CNS diseases. In this study, the pure enantiomers of evodiamine were prepared in large quantities via chemical resolution. Their structures were elucidated by MS, NMR and ECD. The optical purity was determined to be as high as 99.8 %. The differences of the enantiomers in protective effect against neuronal cell injury were evaluated using MTT assay. Notably, R-(-)-evodiamine showed better neuroprotection effects against H₂O₂-induced damage in PC12 cells. An efficient HPLC-MS/MS method for determination of evodiamine enantiomers in rat plasma and brain was developed and verified. Satisfactory enantioseparation of evodiamine was achieved on a Chiralcel OD-RH column with the mobile phase of acetonitrile-water (70:30, v/v) at a flow rate of 0.6 mL/min. The analytes were measured under multiple reactions monitoring (MRM) mode with m/z 304.3→134.3 for evodiamine and m/z 289.3→97.1 for testosterone (IS) using electrospray ionization source (ESI) in the positive ion mode. The method was validated and fulfilled the requirements of bioanalysis. It was successfully applied to study the stereoselectivity of evodiamine in pharmacokinetics and the ability across the blood-brain barrier in rats. After oral and intravenous administration of racemic evodiamine to rat, the area under the concentration-time curve of R-evodiamine was noticeably 1.70 and 1.33 times higher than those of S-evodiamine, respectively. Furthermore, while there was no significant difference in the B/P values, the concentration of R-(-)-evodiamine in the brain was approximately 1.31 times greater than that of S-(+)-evodiamine. The results indicated that evodiamine enantiomers exhibited significant stereoselectivity in pharmacokinetics after oral administration and intravenous administration. While the two enantiomers showed no significant stereoselectivity in the ability across the blood-brain barrier. These findings provided new insights into the development of a single enantiomer of evodiamine as a potential drug candidate for the treatment of CNS diseases.

Separation of a monoclonal antibody (mAb) from impurities was examined on different cation exchange resins (CEX), including POROS XS, POROS HS, NUVIA S, and NUVIA HRS. Impurities mainly consisted of cell culture-derived mAb fragments, or lysozyme, that mimicked the presence of an adsorbing protein of low molecular weight. The choice between the flowthrough mode and the bind-and-elute mode for the purification was guided by the shape of the adsorption isotherm. If the slope of the isotherm chord of mAb was markedly lower than that of the impurities at the loading concentration used, the flowthrough mode performed efficiently. If the opposite held, the use of the bind-and-elute mode was preferable. The existence of an intersection of the isotherm courses indicated the possibility of separation in both flowthrough and bind-and-elute modes in properly selected concentration ranges. For the above reasons, the flowthrough separation of the mAb from its fragments was the most effective for the POROS XS resin, and mAb from LYZ for the NUVIA S resin. Moreover, for the NUVIA S resin, both flowthrough and bind-and-elute modes could be efficiently used for the separation of the mAb from its fragments.

Chirality is a fundamental property in nature, and chiral molecules are closely related to human health and the origin of life. Therefore, the exploration and preparation of optically active compounds of paramount importance. Membrane separation is a large-scale and continuous separation technique that has been developing quickly in recent years. It has many potential applications, particularly in chiral membrane separation technology, which is currently a hotspot for study. Depending on the types of membranes, chiral membranes can be divided into two categories: chiral solid membranes and chiral liquid membranes. Solid membranes outperform the others in terms of better mechanical performance and separation efficiency. This review presents in-depth summaries of chiral solid membranes made of different materials, and their applications in drug separation. It also providing insights into the potential for the future development of chiral solid membranes.

Benzophenone derivatives (BPs), as synthetic chemicals widely used in personal care products, have drawn increasing attention due to their potential health risks. However, monitoring BPs in biological samples remains challenging due to their complex matrices and the deficiency in sensitivity and selectivity in current methods. Herein, a method combining hierarchically flower-like hollow covalent organic frameworks (HFH-COFs) with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established for the enrichment and detection of BPs in serum samples. The HFH-COFs were synthesized at room temperature and employed as an adsorbent due to their advantageous properties. The as-prepared HFH-COFs exhibited high specific surface area (2286.53 m²/g), excellent chemical stability, and good thermal stability, making them ideal for efficient enrichment applications. Under optimized experimental conditions, five BPs were effectively enriched and quantified by HPLC-MS/MS in the range of 50.0-5000.0 ng/L with good linearity (r > 0.9992). The limit of detections was 0.5-10.0 ng/L. Furthermore, HFH-COFs showed high enrichment factors even over multiple adsorption-desorption cycles. This study proposed a reliable and efficient method for monitoring endocrine-disrupting compounds in complex biological samples and highlighted the potential of HFH-COFs as a superior adsorbent material for BP.

Recent advancements in technology, such as the emergence of artificial intelligence (AI) and machine learning (ML), have facilitated the progression of the biopharmaceutical industry toward the implementation of Industry 4.0. As per the guidelines set by the USFDA, process validation for biopharmaceutical production consists of three stages: process design, process qualification, and continuous process verification (CPV). This paper proposes a strategy for achieving CPV for a cation exchange chromatography unit operation, emphasizing the urgent need for such strategies in the biopharmaceutical industry. Statistical process control (SPC) charts were generated based on real-time measurement of the various critical process parameters (CPPs) measured via in-built sensors (pH, conductivity, UV, and delta column pressure) as well as of critical quality attributes (CQAs) like charge variant composition (Raman spectroscopy) and concentration (Near infrared spectroscopy). A Python-based program was created to read these SPC charts and respond to any deviation. The developed models for NIR coupled DNN PAT tool and Raman coupled DNN PAT tool exhibited satisfactory R² values (> 0.90), highlighting the statistical significance of the proposed model. Further, the control strategy designed based on Raman spectroscopy for charge variant composition in CEX eluate has been demonstrated by intentional perturbations in the CEX load. The resulting CEX eluate output showed a consistent charge variant composition as that of control runs (acidic ∼20 ± 2 %, main ∼62 ± 2 % and basic ∼18 ± 2 %). It has been demonstrated how an appropriate selection of analyzers, soft sensors, and advanced data analytics can be used to execute CPV and enable the biopharmaceutical industry to implement Industry 4.0.

Non-destructive chromatographic methods were used to determine the hold-up volumes of four self-packed columns containing embedded phosphate groups. The stationary phases are named Diol-P-C10, Diol-P-C18, Diol-P-Benzyl and Diol-P-Chol. The hydrophobicity of organic ligands bound to the phosphate group increases in the benzyl< decyl < octadecyl

Polyethylene glycol (PEG) is one kind of polymeric pharmaceutical excipient widely used in pharmaceutics. The critical quality attributes (CQAs) are essential to their physicochemical properties and functions. However, there is no effective strategy to rapidly and simply analyze PEG multi-CQAs. Herein, a novel strategy was developed to simultaneously evaluate four PEG CQAs including average degree of polymerization, average molecular weight, weight-average molecular weight and polydispersity based on comprehensive identification and mathematical models of PEG components. In this strategy, an ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) method was established and different types and concentrations of mobile phase additives were optimized to overcome the mass discrimination effect of PEG components. MS data was deconvoluted by molecular feature extraction to identify PEG components with multi-charged quasimolecular ions. A total of 168 PEG components were identified in PEG mixture samples. Mathematical models were established based on the logarithmic relation between the degree of polymerization and retention time and a theoretical database including 220 detected and predicted PEG components was constructed to rapidly recognize and identify PEG components in PEG excipients and preparations samples. The calculation formulae for multi-CQAs using UHPLC-Q-TOF/MS analysis results were created, then the strategy workflow to evaluate multi-CQAs was established and validated by PEG standards, showing high efficiency for quality control of PEG excipients and their preparations.