J Chromatogr A [JOURNAL]
Sun
200 papers
Efficient extraction of fluorinated non-steroidal androgen receptor antagonists on a novel trifluoromethyl functionalized magnetic microporous organic network.
Liu C, Kang JM, Cui YY … +1 more , Yang CX
J Chromatogr A · 2026 Aug · PMID 42251845 · Publisher ↗
Given the widespread clinical use, environmental persistence, and potential ecological and health risks of non-steroidal androgen receptor antagonists (NSAAs), developing a highly selective and sensitive method to detect...
Given the widespread clinical use, environmental persistence, and potential ecological and health risks of non-steroidal androgen receptor antagonists (NSAAs), developing a highly selective and sensitive method to detect their residues in aquatic environments is of significant importance and poses considerable challenges. Based on the hydrophobicity and fluorine-containing characteristics of NSAAs, this study designed and prepared a novel trifluoromethyl functionalized magnetic microporous organic network (MMON-CF) for the efficient and selective magnetic solid-phase extraction (MSPE) of three typical NSAAs, namely flutamide, bicalutamide, and enzalutamide, from environmental water samples before HPLC-UV quantification. The as-prepared MMON-CF features a uniform core-shell structure, high specific surface area, good hydrophobicity, and superparamagnetism. These characteristics endow the material with outstanding extraction capability and selectivity toward the target NSAAs, driven by distinctive F-F contacts, hydrogen-bonding interactions, hydrophobic adsorption, and π-π conjugation. Under optimum extraction parameters, the developed MMON-CF-MSPE-HPLC-UV method demonstrated satisfactory analytical performance for the three analytes, including low limits of detection (0.1-0.2 μg L), a broad linear range (0.5-1000 μg L), high enrichment factors (91.2-95.6), minimal adsorbent dosage (3 mg), and fast extraction equilibrium (6 min). The present work underscores the promising application potential of fluorinated MON-based materials in the sample pretreatment of fluorinated pharmaceutical contaminants from complicated environmental matrices.
Isolation and purification of extracellular vesicles based on dual mechanisms of charge/size exclusion by quaternized magnetic nanomaterials.
Qiang Z, Yang Z, Hu W … +2 more , Zhang L, Zhang W
J Chromatogr A · 2026 Aug · PMID 42250512 · Publisher ↗
Extracellular vesicles (EVs), as key mediators of intercellular communication, are widely present in various biological samples. In this study, chitosan (CS) and polyethyleneimine (PEI) with different molecular weights w...
Extracellular vesicles (EVs), as key mediators of intercellular communication, are widely present in various biological samples. In this study, chitosan (CS) and polyethyleneimine (PEI) with different molecular weights were grafted onto FeO microspheres, followed by quaternization to yield two series of multifunctional brush-like materials denoted as FeO@QCS and FeO@QPEI. The quaternary ammonium groups efficiently capture EVs via electrostatic binding to membrane phosphate groups. Meanwhile, the grafted CS and PEI chains of different molecular weights form brush layers with tunable sieving properties, enabling size‑selective enrichment of EVs via the size exclusion effect. With moderate chain length and an extended polymer brush conformation, FeO@QCS (200 kDa) captured EVs from fetal bovine serum (FBS) with the broadest size distribution. To isolate EVs from biological samples with high protein interference, we developed a charge/size synergy strategy. First, FeO@PAA, a polyacrylic acid (PAA)-coated anionic magnetic nanoparticle, was used to adsorb positively charged contaminant proteins. Subsequently, FeO@QCS (200 kDa) was employed to capture EVs and residual proteins, followed by salt-gradient elution to remove negatively charged contaminant proteins and release EVs. This strategy successfully achieved a protein removal efficiency of 96.9% and an EV recovery rate of 87.8% for milk samples, identifying 236 EV-characteristic proteins. This method was further applied to the enrichment of human plasma EVs, and downstream proteomic analysis identified 484 EV proteins.
Optimised extraction and HPLC-DAD determination of steroidal glycoalkaloids in potato tubers: Analytical validation and environmental sustainability evaluation.
Ben Ammar H, Dolničar P, Pipan B … +1 more , Sinkovič L
J Chromatogr A · 2026 Aug · PMID 42250511 · Publisher ↗
Steroidal glycoalkaloids (α-solanine and α-chaconine) are major potato toxins whose accurate quantification is often challenged by matrix effects and chromatographic selectivity. This study reports the optimisation and v...
Steroidal glycoalkaloids (α-solanine and α-chaconine) are major potato toxins whose accurate quantification is often challenged by matrix effects and chromatographic selectivity. This study reports the optimisation and validation of a robust reversed-phase HPLC-DAD method for the determination of glycoalkaloids in potato tissues, combined with a systematic assessment of the environmental sustainability of the analytical workflow. Extraction conditions were optimized by integrating systematic solvent screening with a factorial experimental design to evaluate the effect of key operational variables on glycoalkaloid recovery and refine extraction performance The resulting extraction medium improved extract cleanliness and chromatographic stability. A subsequent C18 solid-phase extraction SPE step further reduced matrix effect and enhanced analytical selectivity. Chromatographic separation was achieved on a conventional C18 column using an acetonitrile-water gradient, providing baseline resolution (Rs > 1.5) of α-solanine and α-chaconine with stable diode-array detection (DAD) at 205 nm. The method was validated according to ICH Q2(R2) and AOAC guidelines, demonstrating excellent linearity (R > 0.995), low limits of detection (0.462-0.767 µg/mL) and quantification (1.540-2.558 µg/mL), high precision (≤ 5% RSD), and recoveries of 90-105%. Robustness testing confirmed minimal sensitivity to routine variations in chromatographic parameters. Application to potato breeding lines demonstrated reliable quantification and revealed genotype-dependent variation in glycoalkaloid content. The environmental assessment of the analytical procedure was evaluated using Analytical Eco-scale, GAPI and AGREE metrics, demonstrating reduced solvent consumption, avoidance of strongly acidic extraction conditions, and a simplified sample preparation workflow. The proposed HPLC-DAD workflow provides a validated, high-performance, and environmentally conscious approach for routine GA quantification, suitable for food-safety monitoring, regulatory compliance and breeding programme applications.
Continuous molecular separation in a polymer-introduced circular tube via diffusion, forced convection and adsorption.
Toyoshima Y, Morisada S, Ohto K … +1 more , Kawakita H
J Chromatogr A · 2026 Aug · PMID 42250510 · Publisher ↗
Membrane filtration is commonly used for the separation of biomacromolecules; however, fouling often leads to a loss in the recovery of the target materials. As a separation material capable of isolating molecules and po...
Membrane filtration is commonly used for the separation of biomacromolecules; however, fouling often leads to a loss in the recovery of the target materials. As a separation material capable of isolating molecules and polymers on the order of several tens of nanometers, we have newly prepared a tubular device whose inner surface was modified with a cationic polymer, poly(2‑(dimethylamino)ethyl methacrylate) (polyDMAEMA). Small molecules and particles diffuse in the radial direction and are adsorbed onto the polymer layer, whereas larger particles are transported axially by forced convection and elute from the tube before reaching the adsorption layer, size‑based separation becoming feasible. Compared with gel-permeation chromatography (GPC), this method allows continuous flow through the tube, enabling higher processing throughput, and clogging does not occur because the separation unit is a simple cylindrical tube. The number density of polyDMAEMA introduced into the polyimide tube was assumed to be 0.57 chains/nm², indicating the formation of a dense polymer layer. When solutions of bromophenol blue (BPB, Mw 669) and poly(styrene sulfonic acid) (PSS, Mw 70 kDa) were permeated through the tube, BPB was adsorbed whereas PSS eluted immediately, demonstrating that the polymer‑modified tube can achieve separation. The breakthrough curves were fitted using partial differential equations to obtain the mass‑transfer coefficient, maximum adsorption capacity, and dispersion coefficient, which were then correlated with the Peclet and Damköhler numbers. Using these correlations, the separation efficiency of BPB and PSS at different flow rates was predicted, demonstrating that efficient separation is achieved at low flow rates. This proposed tube shows high potential for application in the separation of biomolecules and particles.
Streamlined LC-HRMS-based determination of sterols and triterpenic alcohols in edible oils for authentication purposes.
Caño-Carrillo I, Schiavone B, Rascón AJ … +2 more , Gilbert-López B, García-Reyes JF
J Chromatogr A · 2026 Aug · PMID 42247912 · Publisher ↗
Sterol analysis is a key parameter for assessing the authenticity and quality of olive oil, as defined by official methods. Nevertheless, these protocols are labor-intensive and require multiple preparation steps, includ...
Sterol analysis is a key parameter for assessing the authenticity and quality of olive oil, as defined by official methods. Nevertheless, these protocols are labor-intensive and require multiple preparation steps, including sample fractionation and derivatization. In the present work, a simplified analytical methodology is proposed for the determination of free sterols and triterpenic alcohols, eliminating these time-consuming procedures. The method is based on the direct analysis of saponified extracts, prepared according to the official protocol, followed by a single dilution step and analysis by liquid chromatography coupled to high-resolution mass spectrometry with electrospray ionization (LC-ESI-HRMS). To enhance the ionization efficiency of free sterols, which exhibit low response under conventional ESI conditions due to their non-polar nature, ammonium formate was added to the mobile phase. The analytical performance of the method was evaluated in terms of linearity, reproducibility, and limits of quantification to support its suitability for comparative fingerprinting analysis. Based on the obtained sterol profiles, several compounds were identified as potential markers for differentiating edible oils, including extra virgin olive oil, pomace olive oil, rapeseed oil, avocado oil, almond oil, and sunflower oil. The application of principal component analysis (PCA) to these data further enabled the distinction of extra virgin olive oil from the remaining vegetable oils, demonstrating the discriminatory potential of the proposed approach for oil characterization and classification.
GC‑EI‑MS and GC‑CI‑MS characterization of n-Alkenyl mono- and diesters of Alkylphosphonic acids with retention index correlations.
Boczkowski M, Nawała J, Popiel S … +1 more , Milczarek JM
J Chromatogr A · 2026 Aug · PMID 42247911 · Publisher ↗
Microscale syntheses of thirty‑two n-alkenyl derivatives of alkylphosphonic acids - sixteen symmetric O,O-dialkenyl diesters and sixteen O-alkenyl monoesters (analyzed as their O-trimethylsilyl derivatives) were carried...
Microscale syntheses of thirty‑two n-alkenyl derivatives of alkylphosphonic acids - sixteen symmetric O,O-dialkenyl diesters and sixteen O-alkenyl monoesters (analyzed as their O-trimethylsilyl derivatives) were carried out for comparative mass‑spectrometric and chromatographic studies. These compounds fall under Schedule 2.B.04 of the Chemical Weapons Convention (CWC); however, twenty‑four of them are absent from major mass‑spectral libraries (NIST 23, OCAD v28_2026, VGWD_2026) and lack published retention index (RI) values. GC‑EI‑MS and GC‑CI‑MS analyses were performed, and methane PCI conditions yielded abundant protonated molecules [M+H], which frequently constituted the base peak and provided reliable confirmation of molecular weight. Distinct fragmentation behavior enabled classification of the compounds into two structural groups: derivatives with terminal double bonds and crotyl derivatives, the latter showing suppressed [M+H] intensities and altered adduct formation. For all homologous series, RI values showed linear correlations with the number of carbon atoms in the alkenyl chain or, in the case of crotyl derivatives, with the alkyl group attached to phosphorus. The generated EI and PCI mass-spectral data, diagnostic ions, and experimental and predicted RI values expand the analytical basis for identification of CWC‑relevant compounds. All results have been submitted for incorporation into the OPCW Central Analytical Database (OCAD) to support chemical-weapons verification and non‑proliferation efforts.
An online packing strategy for high volume injection in sensitivity-enhanced UPLC-MS/MS analysis of 30 veterinary drugs in beef.
Ji B, Zhang M, Luo Y … +6 more , Hou Z, Zhao F, Zhang M, Xu X, Li J, Bai Y
J Chromatogr A · 2026 Aug · PMID 42247910 · Publisher ↗
In this study, an online packing strategy was proposed for vortex mixing-enhanced high volume injection in ultrasensitive UPLC-MS/MS analysis of 30 veterinary drugs in beef. Spherical glass beads were densely packed into...
In this study, an online packing strategy was proposed for vortex mixing-enhanced high volume injection in ultrasensitive UPLC-MS/MS analysis of 30 veterinary drugs in beef. Spherical glass beads were densely packed into a custom-fabricated hollow stainless steel pre-column to achieve efficient vortex-induced mixing with the initial weak mobile phase, thus enabling online sample stacking at the analytical column inlet. Sample elution strength was effectively attenuated via online vortex-enhanced mixing within the packing column assembly, and the inherent solvent imbalance in high volume injection was effectively mitigated. Key parameters including particle size, inner diameter, column length, flow direction, and flow rate demonstrated significant influence for targeted drugs. Method validation demonstrated excellent linearity across 0.125-100 μg/kg, with coefficients of determination (R²)>0.998. Matrix effects were quantified as -17.7% to 17.9%. Spiked recovery assays at 2, 10, and 20 μg/kg yielded acceptable accuracy: 70.9%-111.8%, 60.5%-100.1%, and 63.0%-104.8%, respectively. Intra- and inter-day precision displayed favorable relative standard deviations (RSDs) ≤17.3%. Analytical sensitivity was characterized by limits of detection (LODs, 0.03-1.7 μg/kg) and quantification (LOQs, 0.1-4.2 μg/kg). The utilized strategy achieved 10.9 ± 3.7-fold peak area enhancement for target veterinary drugs via 20 μL injection (vs. conventional 2 μL), resolving the persistent "solvent effect" imbalance in high loading injection and exhibiting excellent compatibility with conventional LC-MS systems without hardware/software upgrades. The packed column exhibits intrinsic practical advantages, encompassing streamlined structural design, straightforward installation, and economical packing materials, thereby underscoring its versatility as a valuable analytical tool for widespread application in trace-level substance monitoring.
A proof-of-concept evaluation of an ROI-MCR and HILIC-based method for screening environmental contaminants in surface and groundwater.
Pellacani S, Ronchetti F, Cerrato A … +6 more , Capriotti AL, Cocchi M, Collischonn L, Durante C, Perra G, Strani L
J Chromatogr A · 2026 Aug · PMID 42247909 · Publisher ↗
This study presents a preliminary evaluation of an untargeted approach for the detection of persistent and mobile organic contaminants, PMOCs, in surface and groundwater samples from northern Italy. The main objective wa...
This study presents a preliminary evaluation of an untargeted approach for the detection of persistent and mobile organic contaminants, PMOCs, in surface and groundwater samples from northern Italy. The main objective was to assess the performance and applicability of an untargeted screening workflow based on the Regions of Interest- Multivariate Curve Resolution (ROI-MCR) approach on a data set collected by liquid chromatography coupled with high-resolution mass spectrometry (LCHRMS). Particular attention was given to ensure the reliability and robustness of the extracted spectral features. A targeted analysis was also performed on thirteen PMOCs, eight pharmaceuticals, three central nervous system (CNS) stimulants, one pesticide, and one artificial sweetener, which were selected for their physicochemical properties and their high mobility in aquatic environments. The untargeted screening led to the tentative identification of twenty-four chemical compounds belonging to different classes such as pharmaceuticals, cosmetics, pesticides and industrial products. Their distribution was analysed in relation to the geological and hydrological features of the study area, highlighting the influence of local environmental conditions on the occurrence and mobility of contaminants.
On-site multi-matrix profiling of per- and polyfluoroalkyl substances using mobile liquid chromatography - mass spectrometry.
Mikhail IE, Mai Y, Lebanov L … +6 more , Lam SC, Durage KK, Firme B, Askeland M, Gooley A, Paull B
J Chromatogr A · 2026 Aug · PMID 42242130 · Publisher ↗
This study demonstrates rapid, on-site detection of per- and polyfluoroalkyl substances (PFAS) at a legacy-impacted site along Barilla Rivulet in Cambridge, Tasmania, using a mobile liquid chromatography-mass spectrometr...
This study demonstrates rapid, on-site detection of per- and polyfluoroalkyl substances (PFAS) at a legacy-impacted site along Barilla Rivulet in Cambridge, Tasmania, using a mobile liquid chromatography-mass spectrometry (LC-MS) laboratory (lab-in-a-van). Ten key PFAS were monitored in freshwater, soil, and soil pore-water samples, providing an integrated view of their distribution and mobility. Sample collection, on-site preparation, and LC-MS analysis of standards and 13 environmental samples were finished within six hours. The compact LC-MS system, pallet-framed in a van, combines a Versiti liquid chromatograph with a Shimadzu autosampler and single quadrupole mass spectrometer. The system was transported from Victoria to Tasmania, where on-site analysis was conducted using an LC-MS method with a total run time of <8 min and limits of detection (LODs) ranging from 0.06 to 0.84 µg/L. Inter-day precision showed %RSD ≤18.3%, and on-site analysis of a certified proficiency test soil sample yielded deviations of 4-35% relative to reference values. Freshwater samples from Barilla Rivulet and soil pore-water samples collected via a ceramic pore-water sampler were processed using a rapid solid-phase extraction (SPE) protocol, completed in 30 min per batch of 3-5 samples, while soil samples were extracted using a solid-liquid extraction (SLE) protocol. The combined concentration of the targeted PFAS ranged from 1.5-2.4 µg/L in freshwater samples, 5.9-22.9 µg/kg in soil, and 0.3-1.9 µg/L in soil pore-water. Clear distinctions were observed in the distribution of short- and long-chain homologues, as well as between carboxylic- and sulfonic-acid PFAS across soil and soil pore water. This study demonstrates that a rapid multi-matrix PFAS survey can be conducted on-site using mobile LC-MS, providing a practical solution for time-critical environmental assessments and supporting data-driven remediation decisions.
A targeted partial reduction cyanylation strategy coupled with HRMS for accurate disulfide bridge mapping in disulfide rich cyclic peptides.
Chaturvedi S, Sneha K, Sharma N
J Chromatogr A · 2026 Aug · PMID 42242129 · Publisher ↗
Determining disulfide bridge connectivity in disulfide rich peptides presents significant analytical challenges, primarily due to the presence of isobaric species that cannot be distinguished by intact mass analysis alon...
Determining disulfide bridge connectivity in disulfide rich peptides presents significant analytical challenges, primarily due to the presence of isobaric species that cannot be distinguished by intact mass analysis alone. This study describes a targeted approach based on controlled partial reduction followed by cyanylation for the reliable assignment of disulfide linkages. The method was evaluated using representative approved cyclic peptide therapeutics, specifically Linaclotide, Plecanatide, and Ziconotide. These peptides were selected as model due to their clinical relevance, well-defined and diverse disulfide bond architectures, and their status as benchmark examples of disulfide-rich therapeutics. Partial reduction was optimized to generate mono-reduced intermediates, which were subsequently derivatized through cyanylation. This modification enabled selective cleavage at cysteine residues, producing structurally informative fragments after final reduction. These fragments were characterized using high-resolution mass spectrometry (HRMS), facilitating clear identification of disulfide connectivity. The proposed workflow demonstrates high reproducibility and analytical consistency, with excellent mass accuracy and enhanced structural resolution relative to conventional methodologies. Notably, it enables reliable differentiation of disulfide isomers that are otherwise indistinguishable using routine analytical techniques. Overall, this study establishes a practical and robust method for disulfide bond mapping in cyclic peptides, with broad applicability for structural characterization and quality assessment and don't require enzymatic digestion or specialized instrumentation.The methodology was successfully validated using Linaclotide, Plecanatide, and Ziconotide, which contain three, two, and three disulfide bridges, respectively.
High correlation of HPSEC-MALLS-based viral particle quantification to infectivity enables quality-by-design for recombinant vesicular stomatitis virus process development.
Li Z, Jia X, Xie B … +4 more , Zhao J, Ma Y, Su Z, Zhang S
J Chromatogr A · 2026 Aug · PMID 42242128 · Publisher ↗
Traditional viral titer methods (e.g., TCID₅₀) are activity-based and time-consuming, limiting rapid process development and quality by design (QbD) for viral vector production. Here, using recombinant vesicular stomatit...
Traditional viral titer methods (e.g., TCID₅₀) are activity-based and time-consuming, limiting rapid process development and quality by design (QbD) for viral vector production. Here, using recombinant vesicular stomatitis virus (rVSV) as a model, we established a method based on high performance size exclusion chromatography coupled with multi angle laser light scattering (HPSEC -MALLS) to simultaneously monitor viral particle concentration and purity. Importantly, the physical particle concentration measured by HPSEC-MALLS correlated strongly with biological infectivity (TCID₅₀), yielding an R² of 0.975. Leveraging this correlation, we achieved real-time quality control across downstream and upstream processes. During the upstream culture stage, a multiplicity of infection (MOI) of 0.1 maximized particle production. For purification, Capto Core 700 multimodal chromatography achieved 83.53% particle recovery while removing >99% of host cell proteins and nucleic acids. In formulation studies, sucrose preserved 95.20% particle stability after five weeks at 4 °C, whereas trehalose yielded 94.92% retention following lyophilization. This HPSEC-MALLS platform enables rapid, label-free, multi parameter quality control throughout the entire viral vector process, accelerating both process optimization and clinical translation.
Addressing method transfer and robustness challenges using design space modeling.
Zöldhegyi A, Horváth K, Molnár I … +1 more , Kormány R
J Chromatogr A · 2026 Aug · PMID 42242127 · Publisher ↗
In high-performance liquid chromatography (HPLC), robust and easily transferable analytical methods are essential to ensure consistent performance throughout the entire lifecycle of an analytical procedure, including unf...
In high-performance liquid chromatography (HPLC), robust and easily transferable analytical methods are essential to ensure consistent performance throughout the entire lifecycle of an analytical procedure, including unforeseen future applications. Nevertheless, robustness-, and ruggedness-related issues are frequently reported in industrial practice, particularly during method transfer between laboratories. These challenges often arise from incomplete method understanding and insufficient consideration of HPLC system-related effects, such as dwell volume, extra-column contributions and other, at first less evident, instrument-to-instrument variations in solvent delivery, mixing behavior and column thermal control. In this context, modeling approaches aligned with Analytical Quality by Design (AQbD) principles provide valuable support for both proactive method development and reactive troubleshooting. In the current work, we used DryLab modeling Design Spaces (DSs) to create digitized modeling fingerprints of various instruments, enabling extensive in silico investigations, including in-depth assessment of method transferability and evaluation of subtle, instrument-dependent robustness characteristics.
Advanced modeling techniques in hydrophobic interaction chromatography (HIC).
Beryamysoltan S, Guzman-Tinoco J, Gudena K … +4 more , Gerbrich C, Cano A, O'Connor T, Chattoraj S
J Chromatogr A · 2026 Aug · PMID 42235435 · Publisher ↗
Hydrophobic Interaction Chromatography (HIC) is widely used in biopharmaceutical downstream processing for protein separation under mild and aqueous conditions. Accurate modeling of HIC for optimizing monoclonal antibody...
Hydrophobic Interaction Chromatography (HIC) is widely used in biopharmaceutical downstream processing for protein separation under mild and aqueous conditions. Accurate modeling of HIC for optimizing monoclonal antibody (mAb) monomer and aggregate separation remains challenging, primarily due to complex resin-protein interactions across diverse operating ranges. This study compares five advanced modeling approaches, mechanistic models, residual-based and differential parallel hybrid models, a serial hybrid model, and a physics informed neural network (PINN), to predict HIC behavior under varied conditions. Model performance was evaluated using qualitative trend analysis and quantitative metrics (R², RMSE, MBE). Among the tested approaches, the differential parallel hybrid model consistently demonstrated superior performance, accurately capturing the complex dynamics of HIC, including breakthrough, plateau, wash, and tailing phases for both monomer and aggregate species. It achieved remarkable accuracy for aggregate predictions (R² = 0.99, RMSE = 0.02, MBE = 0.01) and similarly strong performance for monomer (R² = 0.99). These findings underscore that sophisticated hybrid modeling strategies, especially the differential parallel approach, offer robust and highly accurate predictive capabilities essential for optimizing complex downstream bioprocesses like HIC.
Interpretable generative machine learning platform for chronological prediction of forensic paper aging via GC-IMS volatiles characterization in judicial authentication.
Lu W, Kong L, Zhang L … +4 more , Ma J, Qi Y, Lei M, Li X
J Chromatogr A · 2026 Aug · PMID 42229280 · Publisher ↗
The determination of paper aging is crucial for forensic document examination, enabling the identification of temporal origin in forgery or fraud cases. Paper aging is difficult to distinguish due to the high composition...
The determination of paper aging is crucial for forensic document examination, enabling the identification of temporal origin in forgery or fraud cases. Paper aging is difficult to distinguish due to the high compositional complexity, intricate temporal evolution mechanisms, and challenges in tracing diagnostic markers, limiting reliable chronological authentication. Herein, an interpretable generative end-to-end machine learning platform integrating gas chromatography-ion mobility spectrometry (GC-IMS) with machine learning was established for prediction of the temporal origin of forensic paper aging. Sixty-three differential volatiles were identified in paper materials via GC-IMS analysis. Chronological classification and regression machine learning models were constructed based the volatile fingerprints from papers aged 1 to 35 years. The CatBoost model achieved the best overall performance in both age-class identification and year prediction based on characteristic volatile profiles. SHAP (SHapley Additive exPlanations) model identified key markers as the most influential predictors, such as 3‑hydroxy-2-butanone-D, Hydroxyacetone, Cyclopentanone, and Isomenthone, enabling paper samples specific attribution of prediction outcomes. An end-to-end chronological prediction software tool was developed to automate data import, age prediction, and interpretation result generation, thereby improving its practicality and accessibility for forensic applications. Overall, this study provides a deployable analytical framework for interpretable chronological prediction of forensic paper aging and is expected to generate reliable results for judicial authentication.
Comprehensive optimization of chromatographic separation and iterative data acquisition for liquid chromatography-tandem mass spectrometry non-targeted plasma metabolomics: Enhancing feature-based molecular networking.
Yang J, Lai X, Liu Q … +3 more , Tao Y, Huang H, Ding B
J Chromatogr A · 2026 Aug · PMID 42229279 · Publisher ↗
Liquid chromatography-tandem mass spectrometry (LC-MS/MS) non-targeted plasma metabolomics is essential for biomarker discovery, yet the lack of standardized analytical protocols often compromises data reliability. In th...
Liquid chromatography-tandem mass spectrometry (LC-MS/MS) non-targeted plasma metabolomics is essential for biomarker discovery, yet the lack of standardized analytical protocols often compromises data reliability. In this study, we systematically optimized the entire metabolomics workflow, focusing on the integration of feature-based molecular networking (FBMN) to enhance metabolite annotation. Critical parameters, including protein precipitation chemistry, chromatographic selectivity, and data acquisition strategies, were comprehensively assessed. Optimal extraction was achieved using a methanol/ethanol (1:1, v/v) mixture at a 1:4(v/v) sample-to-solvent ratio. For chromatographic separation, an XBridge BEH C18 column outperformed alternatives. Superior peak capacity and ionization efficiency were obtained using 0.1% formic acid (or 10 mM ammonium acetate with 0.1% formic acid) in positive mode, and 10 mM ammonium formate with 0.1% acetic acid in negative mode. While the timing of internal standard addition did not significantly alter the metabolic profile, instrument signal stability became a critical factor for sequences exceeding one week. Notably, the transition to a 100 mm column and the implementation of iterative data-dependent acquisition (DDA) on quality control samples significantly expanded the FBMN size and the number of uniquely annotated compounds. This optimized, robust workflow provides a standardized framework for improving metabolite coverage and annotation confidence in large-scale clinical investigations.
Recycling slalom and hydrodynamic chromatography for the improved characterization and purification of large plasmids and mRNAs in cell and gene therapy.
Gritti F
J Chromatogr A · 2026 Aug · PMID 42229278 · Publisher ↗
The recent re-introduction of slalom chromatography (SC) in 2023 as a bioanalytical technique to solve complex mixtures of large (> 1 MDa) dsDNAs and dsRNAs biopolymers has been particularly useful to distinguish between...
The recent re-introduction of slalom chromatography (SC) in 2023 as a bioanalytical technique to solve complex mixtures of large (> 1 MDa) dsDNAs and dsRNAs biopolymers has been particularly useful to distinguish between extensible, linearized DNAs and more compact, weakly stretchable plasmids. Today, SC using a single GTxResolve 250 Å Slalom Column, MaxPeak Premier Technology 2.5μm, 4.6 × 300 mm, and 40 mM tris-acetate-EDTA as the mobile phase still falls short of achieving baseline separation of supercoiled (sc) and open circular (oc) plasmids under high shear flow conditions due to their quasi-identical entropic elasticity. This separation is critical for the isolation of pure sc plasmids used as the coding DNA template for in vitro transcription of mRNA vaccines. The isocratic baseline separation of a 5486 bp sc plasmid and its nicked, relaxed 5486 bp oc plasmid isoform based on the principle of alternating pumping recycling liquid chromatography (APRLC) under shear flow is investigated. Two twin 30 cm long GTxResolve 250 Å Slalom Columns were connected to a six-port, two-position valve actuated periodically to enable the transfer of the partially resolved target separation zone over multiple cycles. The results obtained at 0.5 mL/min show that the sc plasmid is in fact slightly less retained than its oc plasmid isoform, with a relative retention time of only 1.012. The final results show complete baseline separation after as many as 9 cycles and a total analysis time of less than 30 min. Notably, over successive cycles and repetitive shear events along the column, valve, and tubing, the 5486 bp sc plasmid remains intact, whereas the 5486 bp nicked oc plasmid is progressively degraded into shorter ssDNA strands and dsDNA fragments. The method allows the production of very pure (>95%) sc plasmid with high yield (>95%) prior to IVT of large mRNA vaccines. Finally, we extrapolate the present concept of APRLC to address the highly demanded and high-throughput separation of very large and flexible mRNAs based on the principle of hydrodynamic chromatography using two twin 15 cm long GTxResolve 250 Å Slalom Columns. Results show that 2 and 3 knt mRNAs can be baseline separated in less than 10 min under non-retained and isocratic elution conditions.
Diastereomer separation of phosphorothioate oligonucleotides via conformationally stabilizing ion pairs in reversed-phase liquid chromatography.
Zhang P, Wang T, Jiang S … +4 more , Li Q, Kong W, Yang K, Nan H
J Chromatogr A · 2026 Aug · PMID 42229277 · Publisher ↗
Phosphorothioate (PS) modification is usually incorporated in oligonucleotide structures to improve nuclease resistance and biological activity. In another hand, PS modification introduces chiral centers and formation of...
Phosphorothioate (PS) modification is usually incorporated in oligonucleotide structures to improve nuclease resistance and biological activity. In another hand, PS modification introduces chiral centers and formation of diastereomers, leading to more challenging characterization. Several approaches have been reported to separate diastereomers, including ion-pairing reversed-phase liquid chromatography (IP-RPLC), hydrophilic interaction chromatography (HILIC), and anion exchange chromatography (AEX). The separation mechanisms are based on differences of hydrophobicity, charge and conformation between diastereomers. In this study, we showcase the power of alkyldiamines (ADs) as a new class of ion pairing reagents for oligonucleotide diastereomer separation using two FDA-approved small interfering RNA (siRNA) compounds, Lumasiran and Vutrisiran, and single-stranded sequences derived from the antisense strand of Lumasiran, as model compounds. The alkyldiamine ion-paring (AD-IP) systems showed significantly improved diastereomer separation compared with the widely used triethylamine acetate (TEAA) IP systems, varied selectivity for positional isomers and robust compatibility with denaturing conditions (e.g., high column temperature). This enhanced efficiency may be attributed to conformationally stabilizing effect of the ADs, confirmed by melting temperature (T) measurements. To best of our knowledge, this is the first time that ion pairing reagents with conformation-stabilizing effect are used for both single- and double-stranded oligonucleotide analysis. This work enriches the analytical toolkit for oligonucleotide characterization and may enable batch-to-batch diastereomer distribution monitoring in synthetic phosphorothioate oligonucleotides.
Chiral separation and analysis of sertraline and its stereoisomers by supercritical fluid chromatography: Thermodynamic evaluation and molecular docking simulation.
Li W, Jin W, Ye X … +2 more , Wu Y, Le J
J Chromatogr A · 2026 Aug · PMID 42224807 · Publisher ↗
In this study, a supercritical fluid chromatography (SFC) method was developed for the chiral resolution of sertraline hydrochloride (1S, 4S) and its three stereoisomers (1R, 4R), (1R, 4S), and (1S, 4R) using an amylose-...
In this study, a supercritical fluid chromatography (SFC) method was developed for the chiral resolution of sertraline hydrochloride (1S, 4S) and its three stereoisomers (1R, 4R), (1R, 4S), and (1S, 4R) using an amylose-tris(3,5-dimethylphenylcarbamate) chiral stationary phase (CSP). Among several polysaccharide-based CSPs screened, the Chiralpak AD-H exhibited the superior separation performance. Under optimized chromatographic conditions, using supercritical CO as mobile phase A and a methanol-ethanol mixture (1:1, v/v) containing 0.2% diethylamine (DEA) as mobile phase B, baseline separation of the four stereoisomers was achieved within 15 min at 210 nm. Thermodynamic investigations revealed that the resolution process for the two pairs of enantiomers was enthalpy-driven, whereas the separation of the diastereomers (1R, 4R) and (1R, 4S) was governed by entropy. Furthermore, molecular docking simulations were employed to elucidate the chiral recognition mechanism, showing that the calculated binding energies were in excellent agreement with the experimentally observed elution order. The proposed method was validated and successfully applied to the determination of sertraline in active pharmaceutical ingredients (APIs) and commercial tablets, providing a rapid and eco-friendly analytical tool for quality control.
Analysis of aroma compounds in dried red goji berries (Lycium sp.) after fractionation with countercurrent chromatography.
Zheng Y, Rüttler F, Vetter W
J Chromatogr A · 2026 Aug · PMID 42224806 · Publisher ↗
Capturing as many aroma compounds as possible in a sample is important, as aroma is a crucial factor for the acceptance of food by consumers. Here, we developed and applied a method for the detailed analysis of aroma com...
Capturing as many aroma compounds as possible in a sample is important, as aroma is a crucial factor for the acceptance of food by consumers. Here, we developed and applied a method for the detailed analysis of aroma compounds in dried red goji berries after fractionation by countercurrent chromatography (CCC). Tests with shake flask experiments of seven characteristic aroma compounds resulted in the solvent system n-pentane/dichloromethane/acetonitrile (20:4:20, v/v/v). After CCC separation with a pool of volatile fractions of goji berries obtained by solvent-assisted flavor evaporation (SAFE), the CCC fractions were Vigreux-concentrated and analyzed by gas chromatography with mass spectrometry (GC/MS). Altogether, 49 aroma compounds were detected after CCC fractionation. The parallel use of the conventional fractionation method via column chromatography enabled the detection of 45 aroma compounds. However, only 25 analytes were detected by both methods (24 exclusively by CCC and 20 analytes exclusively by conventional column chromatography). Unexpectedly, some aroma compounds were detected in virtually all CCC fractions. This indicated a particular effect in the CCC analysis of volatile compounds. Such a distribution across many fractions corresponds to a dilution effect which may be the reason that several volatiles could not be detected in the CCC fractions. Accordingly, the combination of both methods will provide the best information on the aroma compound profile.
4-Mercaptobenzenesulfonic acid-functionalized SiO@Au nanoshells for specific enrichment and SALDI-MS detection of quaternary ammonium compounds.
Du M, Chen X, Sun Y … +5 more , Hu J, Wen W, Xu H, Yin Z, Wu X
J Chromatogr A · 2026 Aug · PMID 42217394 · Publisher ↗
The widespread use and persistence of quaternary ammonium compounds (QACs) in food environments raise concerns about their detection at trace levels in complex matrices. In this study, we developed a negatively charged 4...
The widespread use and persistence of quaternary ammonium compounds (QACs) in food environments raise concerns about their detection at trace levels in complex matrices. In this study, we developed a negatively charged 4-mercaptobenzenesulfonic acid functionalized SiO@Au core-shell nanocomposite (MBSA-SiO@Au) that serves as both a selective adsorbent and an efficient surface-assisted laser desorption/ionization (SALDI) matrix. The sulfonate modified gold shell provides a stable negative surface potential to promote electrostatic interactions with cationic QACs, and their plasmonic properties synergistically enhance laser energy absorption and ionization efficiency. Critical enrichment parameters, including adsorbent amount, solution pH, adsorption time, and redispersion volume, were optimized. The optimized method achieved limits of detection of 0.5 ng/mL for paraquat (PQ), dodecyltrimethylammonium chloride (DTAC), and didodecyldimethylammonium chloride (DDAC), and 1.5 ng/mL for dodecyldimethylbenzylammonium chloride (DBAC), with excellent linearity (R ≥ 0.9843), achieving an enrichment factor of approximately 33.3, and a 20- to 40-fold sensitivity enhancement after enrichment. Application to real food samples, including white radish, carrot, and potato, revealed no detectable QAC residues and satisfactory recoveries ranging from 87.0 to 108.8%. The bifunctional MBSA-SiO@Au-based SALDI platform minimizes organic solvent consumption and offers a rapid, green, and sensitive approach for monitoring QACs in food safety applications.
About
- Frequency
- Sun
- Papers found
- 200
- RSS feed
- Subscribe