{"title":"Species-specific optimization of oxylipin ionization in LC-MS: a design of experiments approach to improve sensitivity.","authors":"Louis Schmidt, Ulrike Garscha","doi":"10.1007/s00216-025-05759-6","DOIUrl":"https://doi.org/10.1007/s00216-025-05759-6","url":null,"abstract":"<p><p>Oxylipins are diverse bioactive signaling molecules, which occur in very low concentrations in complex matrices, posing challenges in achieving consistent and sensitive analysis. UHPLC-MS/MS is the preferred technique to separate and quantify these molecules, often optimized using a time-consuming trial-and-error approach. In this study, we applied the design of experiments (DoE) approach to systematically investigate the ionization properties of multiple oxylipin species. Fractional factorial and central composite designs were employed to detect relevant instrument parameters and optimize signal intensity in ESI-MS/MS analysis. Response surface modeling revealed distinct ionization and fragmentation behaviors between polar and apolar oxylipins, driven by their responses to interface temperature and collision-induced dissociation (CID) gas pressure. Particularly, prostaglandins and lipoxins benefit from higher CID gas pressure and lower temperatures compared to the lipophilic HODEs and HETEs to achieve optimal intensity in multiple reaction monitoring analysis. While global source parameters were optimized, analyte-specific entrance/exit potentials and collision energies required individual adjustments. The final method was applied to analyze seven oxylipin classes including leukotrienes, prostaglandins, lipoxins, resolvins, HETEs, HODE<sub>S</sub>, and HoTrEs. Although improvements in lower limits of quantification were modest (< 1 pg on-column), signal-to-noise ratios increased two-fold for lipoxins and resolvins and three- to four-fold for leukotrienes and HETEs, enhancing detection at trace levels. This DoE-guided strategy provides a powerful tool to improve UHPLC-MS/MS analysis of oxylipins across various instrument vendors, guiding the way towards inter-laboratory comparability.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143073376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cost-effective, user-friendly detection and preconcentration of thrombin on a sustainable paper-based electrochemical platform.","authors":"Ada Raucci, Giuseppina Sorrentino, Sima Singh, Nicola Borbone, Giorgia Oliviero, Gennaro Piccialli, Monica Terracciano, Stefano Cinti","doi":"10.1007/s00216-025-05764-9","DOIUrl":"https://doi.org/10.1007/s00216-025-05764-9","url":null,"abstract":"<p><p>Thrombin overexpression in serum serves as a critical biomarker and is implicated in several diseases associated with significant morbidity and mortality. Existing techniques for thrombin detection are time-consuming and require sophisticated equipment and extensive sample preparation procedures, which further delay the detection and increase the cost of the procedure. Early and accessible diagnosis at the point of care, especially in limited-resource countries, represents the first step of clinical interventions. To overcome these limitations, we have proposed an innovative, sustainable paper-based electrochemical detection platform for thrombin. In this work, a sustainable paper-based aptasensor was rationally designed, characterized, evaluated against conventional gold standard plastic-based substrates, and applied to human serum, yielding a detection limit of ~ 60 pM. The present method provides an efficient and user-friendly way for the detection of thrombin and potentially leading to better management and treatment outcomes for patients.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143073231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yun Yang, Jaymin M Patel, Rong-Sheng Yang, Fengfei Ma, Xiangfeng Niu, Yixiao Zhang, Thomas Niedringhaus, Mohammad Al-Sayah, Xiaoyu Yang
{"title":"Determination of the decapping efficiency of THIOMAB™ antibodies with the engineered cysteine in the Fc region for making antibody-drug conjugates by specific hinge fragmentation-liquid chromatography.","authors":"Yun Yang, Jaymin M Patel, Rong-Sheng Yang, Fengfei Ma, Xiangfeng Niu, Yixiao Zhang, Thomas Niedringhaus, Mohammad Al-Sayah, Xiaoyu Yang","doi":"10.1007/s00216-024-05707-w","DOIUrl":"10.1007/s00216-024-05707-w","url":null,"abstract":"<p><p>The site-specific antibody-drug conjugates (ADCs), particularly those utilizing the engineered cysteine in Fc fragments of mAbs (THIOMAB™ antibodies), have emerged as a novel class of biotherapeutics for cancer treatment. The engineered cysteine residues in these antibodies are capped by cysteine or glutathione through a disulfide bond. Prior to conjugation with linker-payloads, these caps need to be removed through a reduction process. However, monitoring the efficiency of the decapping process has been challenging due to the lack of effective analytical methods. Intact reversed-phase liquid chromatography-mass spectrometry and hydrophobic interaction chromatography methods failed to separate decapped and capped intact THIOMAB™ mAbs in our study. Instead the fragmentation of mAbs provided a novel strategy to analyze the decapping effiency. After cleavage using a hinge specific enzyme, the generated Fc fragments with and without cysteine and/or glutathione caps displayed different hydrophobicity and were well separated by RPLC, allowing quantitative determination of the decapping efficiency. Enzymes that cleave both above and below the hinge disulfide bonds were tested. The use of FabALATICA can determine percentages of molecules with 0, 1, and 2 cysteine and/or glutathione caps, respectively, regardless of whether the antibody contains the hinge LALA mutations. On the other hand, FabRICATOR enzyme can only be utilized for antibodies without LALA mutations for the overall decapping percentage and cannot be used to estimate intact antibody each with 0, 1, and 2 caps. Therefore, FabALACTICA cleavage followed by RPLC provides a wider application of monitoring the decapping efficiency of all antibodies with the engineered cysteine in Fc.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":"847-859"},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142833593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cristina Sempio, Jorge Campos-Palomino, Jelena Klawitter, Wanzhu Zhao, Marilyn A Huestis, Uwe Christians, Jost Klawitter
{"title":"Quantification of 11 kratom alkaloids including mitragynine and its main metabolites in human plasma using LC-MS/MS.","authors":"Cristina Sempio, Jorge Campos-Palomino, Jelena Klawitter, Wanzhu Zhao, Marilyn A Huestis, Uwe Christians, Jost Klawitter","doi":"10.1007/s00216-024-05689-9","DOIUrl":"10.1007/s00216-024-05689-9","url":null,"abstract":"<p><p>Recently in the USA, kratom consumers increasingly report use of the plant for self-treatment of mood ailments, the lack of energy, chronic pain, and opioid withdrawal and dependence. Several alkaloids are present in kratom leaves, but limited data are available on their pharmacokinetics/pharmacodynamics, except for mitragynine. To support clinical studies, a high-performance liquid chromatography-tandem mass spectrometry assay for the simultaneous quantification of 11 kratom alkaloids in human plasma was developed and validated. For calibration standards and quality control samples, human plasma was fortified with alkaloids at varying concentrations, and 200 µL were extracted employing a simple one-step protein precipitation procedure. The extracts were analyzed using LC-MS/MS including electrospray ionization (ESI) in positive multiple reaction monitoring (MRM) mode. The lower limit of quantification was 0.5 ng/mL, and the upper limit of quantification was 400 ng/mL for all analytes. Inter-day analytical accuracy and imprecision ranged from 98.4 to 113% of nominal and from 3.9 to 14.7% (coefficient of variance), respectively. The analysis of plasma samples collected during a clinical trial administering capsules containing kratom leaf extract showed that most samples had quantifiable concentrations of mitragynine, 7-OH-mitragynine, speciogynine, speciociliatine, and paynantheine and that mitragynine, speciogynine, and speciociliatine accumulated in human plasma after daily administration over 15 days. An LC-MS/MS assay for the specific quantification of kratom alkaloids including mitragynine and its main metabolites was developed and successfully validated in human plasma. Human plasma samples collected following multiple oral administrations of a controlled Kratom extract documented accumulation of kratom alkaloids over 15 days.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":"761-769"},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142790652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Siqi Cui, Kun Wang, Yuanzhan Yang, Xuefei Lv, Xiaoqiong Li
{"title":"An integrated and paper-based microfluidic system employing LAMP-CRISPR and equipped with a portable device for simultaneous detection of pathogens.","authors":"Siqi Cui, Kun Wang, Yuanzhan Yang, Xuefei Lv, Xiaoqiong Li","doi":"10.1007/s00216-024-05693-z","DOIUrl":"10.1007/s00216-024-05693-z","url":null,"abstract":"<p><p>Point-of-care testing methods are essential for the large-scale diagnosis and monitoring of bacterial infections. This study introduces an integrated platform designed for the simultaneous detection of pathogenic bacteria. Users can simply inject samples into the system, which then conducts the entire procedure in a fully automated manner, eliminating the need for external power sources, all within 60 min or less. The innovative paper-based microfluidic system is capable of lysing bacteria and integrating loop-mediated isothermal amplification (LAMP) with the CRISPR/Cas12a system, achieving this with minimal reagent usage on a single piece of paper. The reaction reagents are pre-fabricated as freeze-dried powder on the paper, allowing for long-term storage. A portable and cost-effective detection device has been designed to provide stable temperature control and analyze fluorescent signals, complementing the paper-based microfluidic system. This compact device measures 150 × 150 × 100 mm, weighs less than 1.8 kg, has an average power consumption of under 15 W, and supports external power supply. The device utilizes non-contact QR codes for information transmission, ensuring functionality even in areas without Internet connectivity. This platform is capable of simultaneously detecting five typical pathogenic microorganisms, with a detection limit of 1 copy/μL. It boasts several advantages, including miniaturization, lightweight design, low power consumption, portability, affordability, rapid detection, and ease of operation, making it highly suitable for on-site detection.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":"785-797"},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142875953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Monica Mazzarino, Francesca Pizzolato, Lenka Honesová, Maria Tsivou, Günter Gmeiner, Peter Van Eenoo
{"title":"LC-HRMS screening procedure for the detection of 11 different classes of prohibited substances in dried urine spots for doping control purposes.","authors":"Monica Mazzarino, Francesca Pizzolato, Lenka Honesová, Maria Tsivou, Günter Gmeiner, Peter Van Eenoo","doi":"10.1007/s00216-024-05697-9","DOIUrl":"10.1007/s00216-024-05697-9","url":null,"abstract":"<p><p>Dried urine spots have recently been proposed as an alternative matrix in the anti-doping field. Drying urine may open the opportunity to limit microbial and thermal degradation of the prohibited substances during transportation to the anti-doping laboratories without the need for refrigeration or freezing. In this study, a multi-targeted initial testing procedure was developed for the determination of 237 prohibited drugs/metabolites from 11 different classes in dried urine spots. The comparability between two different microsampling techniques (i.e., Whatman<sup>®</sup> FTA DMPK-C cards and Mitra<sup>®</sup> tips) was evaluated. The developed method was then used to evaluate the stability of the target compounds in urine for 7 days under different environmental conditions to simulate the transportation of the urine samples from the collection sites to anti-doping laboratories. Sample preparation consists of (i) extraction of the analytes from the collection device using a mixture of acetonitrile/methanol (1/1) for 30 min at 40 °C, (ii) enzymatic hydrolysis, and (iii) sample concentration by solid-phase extraction. Analysis was performed using liquid chromatography coupled to high-resolution mass spectrometry. The entire workflow was validated in terms of specificity (analytes were distinguishable from the matrix interferences), sensitivity (only with the Mitra<sup>®</sup> tips the limits of detection comply with the World Anti-Doping Agency's requirements for the majority of the target compounds), carry-over (no signals in the negative urine injected after the positive urine), matrix effect (16-28% for Mitra<sup>®</sup> tips and 22-35% for DMPK-C cards), and extraction yield (Mitra<sup>®</sup> tips: 51-88%; DMPK-C cards: 40-76%). As proof of concept, authentic urine samples were analyzed: results obtained in dried urine were compared with those of fluid urine, providing good agreement. Stability studies showed that the target compounds were stable for the whole duration of the study (7 days) at -20 and 4 °C in both fluid and dried urine. At 50 °C or at 20-25 °C, several thiazide-based compounds were completely degraded to their degradation product in the first 24 h or after 3-4 days in fluid urine, whereas in dried urine the compounds were detectable for the entire duration of the study.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":"799-820"},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142926152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Matan Birenboim, Nimrod Brikenstein, David Kenigsbuch, Jakob A Shimshoni
{"title":"Aquaphotomics study of fresh cannabis inflorescence: near infrared spectral analysis of water matrix structures.","authors":"Matan Birenboim, Nimrod Brikenstein, David Kenigsbuch, Jakob A Shimshoni","doi":"10.1007/s00216-024-05685-z","DOIUrl":"10.1007/s00216-024-05685-z","url":null,"abstract":"<p><p>Aquaphotomics is an approach that describes the water-light interactions in aqueous solutions or biological systems and retrieves information about the nature of the underlying water-related interactions. We evaluated the water spectral pattern (WASP) and water matrix structure of freshly harvested cannabis inflorescence from seven different chemovars using near-infrared (NIR) spectral data coupled with chemometric models. Six activated water bands-1342, 1364, 1384, 1412, 1440, and 1462 nm, occurred consistently in all of the spectrum exploration steps as well as in the partial least squares-discriminant analysis (PLS-DA) steps. However, according to major class and chemovar aquagram values, the largest spectral variation was associated with the following bands: 1412, 1364, 1374, 1384, 1488, and 1512 nm. A strong positive correlation between 1364, 1374, and 1384 nm aquagram values and a strong negative correlation between 1412 and 1512 nm aquagram values were observed through all aquagram analysis steps. These water activated bands were found to serve as good discriminators and classifiers according to either major class or chemovar. Furthermore, significant differences in the water matrix structure of different cannabis chemovars were observed, with the highest variations associated with the presence of free water molecules, small molecule solvation shells, extent of strongly bound water, and the number of hydrogen bonds per water molecule. Minor cannabinoids and terpenes such as cannabigerolic acid and (-)-guaiol displayed relatively high correlations with these bands. The results of this study suggest that the most accurate way to explore the cannabis inflorescence water matrix spectral pattern is by chemovars and not by major classes.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":"747-760"},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11772404/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142798914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katarína Šťastná, Ludmila Martínková, Lenka Rucká, Barbora Křístková, Romana Příhodová, Pavla Bojarová, Miroslav Pátek
{"title":"Design and development of spectrophotometric enzymatic cyanide assays.","authors":"Katarína Šťastná, Ludmila Martínková, Lenka Rucká, Barbora Křístková, Romana Příhodová, Pavla Bojarová, Miroslav Pátek","doi":"10.1007/s00216-024-05703-0","DOIUrl":"10.1007/s00216-024-05703-0","url":null,"abstract":"<p><p>Determination of free cyanide (fCN) is required for various industrial, environmental, food, and clinical samples. Enzymatic methods are not widely used in this field despite their selectivity and mild conditions. Therefore, we present here a proof of concept for new spectrophotometric enzymatic assays of fCN. These are based on the hydrolysis of fCN affording the readily detectable NADH. fCN is hydrolyzed either in one step by cyanide dihydratase (CynD) or in two steps by cyanide hydratase (CynH) and formamidase (AmiF). An advantage of the latter route is the higher activity of CynH and AmiF compared to CynD. In both cases, the resulting formate is then transformed by an NAD-dependent formate dehydrogenase (FDH). The NADH thus formed is quantified colorimetrically using a known method based on a reduction of a tetrazolium salt (WST-8) with NADH. The developed assays of fCN are selective except for formic acid interference, proceed under mild conditions, and, moreover, fCN is detoxified during the reactions. The assays proceeded in a microtiter plate format. The limit of detection (LOD) and the limit of quantification (LOQ) were lower for the three-enzyme (CynH-AmiF-FDH) method (7.00 and 21.2 µmol/L, respectively) than for the two-enzyme (CynD-FDH) method (10.7 and 32.4 µmol/L, respectively). In conclusion, the new fCN assays presented in this work are selective, high-throughput, do not require harsh conditions, and use only small amounts of chemicals and enzymes.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":"697-704"},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142862862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Henrik Reuter, Dirk Steinritz, Franz Worek, Harald John
{"title":"Phosphonylated tyrosine and cysteine disulfide adducts both generated from immunoglobulin G and human serum albumin indicate exposure to the nerve agent VX in vitro.","authors":"Henrik Reuter, Dirk Steinritz, Franz Worek, Harald John","doi":"10.1007/s00216-025-05762-x","DOIUrl":"https://doi.org/10.1007/s00216-025-05762-x","url":null,"abstract":"<p><p>Pronase-catalyzed proteolysis is shown to produce single amino acid adducts of tyrosine (Tyr) and cysteine (Cys) obtained from both human serum albumin (HSA) and immunoglobulin G (IgG) after in vitro exposure of plasma to the nerve agent VX. Total plasma as well as isolated HSA and IgG yielded the Tyr residue phosphonylated with the ethyl methylphosphonic acid moiety, Tyr(-EMP). Furthermore, a Cys residue adducted with the diisopropylaminoethane thiol leaving group of the agent bound via a disulfide bridge, Cys(-DPAET), was also obtained from both proteins. Even though Tyr(-EMP) represents an internationally well-accepted biomarker of a VX-like agent its origin from plasma IgG has never been shown before. In addition, this is the first time that Cys(-DPAET) is presented as a biomarker of VX exposure clearly identifying the chemical nature of the V-type nerve agent's leaving group. Both biomarkers were detected after selective affinity-based solid-phase extraction (SPE) from plasma that yielded highly purified HSA and IgG as documented by sodium dodecyl polyamide gel electrophoresis (SDS-PAGE). Both biomarkers were found in the corresponding protein bands of HSA and IgG each after in-gel proteolysis with pronase. A micro liquid chromatography-electrospray ionization high-resolution tandem-mass spectrometry method (LC-ESI HR-MS/MS) was developed for the simultaneous detection of Tyr(-EMP) and Cys(-DPAET). The time for proteolysis was optimized for maximum biomarker yield. The method showed excellent selectivity and sensitivity, and the adducted proteins and biomarkers were found to be highly stable during storage. Accordingly, the presented method sheds more light on the molecular toxicology of VX and broadens the spectrum of methods suited for biomedical verification.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143073375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Regulating the surface chemistry of covalent organic frameworks for enhancement cationic dye removal and identification.","authors":"Xiaoli Zhou, Wenjuan Lei, Xiaohuan Qin, Xiaofen Lai, Kun Hu, Shulin Zhao","doi":"10.1007/s00216-024-05687-x","DOIUrl":"10.1007/s00216-024-05687-x","url":null,"abstract":"<p><p>Simultaneous removal and identification of trace-level cationic dye pollutants from water is both important and challenging owing to their highly polar and complex sample matrices. In this study, three covalent organic frameworks (COFs) were synthesized using 2, 4, 6-triformylphloroglucinol with ethidium bromide (EB) containing positively charged groups, 3, 5-diaminobenzoic acid (DABA) containing negatively charged groups, and p-phenylenediamine (Pa) lacking charged groups. These were named EB-COFs, TpPa-1, and DP-COFs, respectively, and were employed as adsorbents for the extraction and identification of cationic dyes. The adsorption performance of the three COFs toward methylene blue (MB) and crystal violet (CV) was investigated. By incorporating carboxyl groups into DP-COFs, the surface chemistry of the adsorbent was effectively tailored, enabling complete exploitation of selective cationic sites. This facilitated dynamic interactions with cationic dyes through multiple adsorption mechanisms, including electrostatic, π-π, and H-bonding interactions. DP-COFs exhibited high adsorption capacities for MB and CV, achieving 383 and 326 mg g<sup>-1</sup>, respectively. The adsorption behavior was further analyzed using adsorption isothermals, kinetics, and thermodynamics. Moreover, DP-COFs were employed as a matrix in laser desorption/ionization time-of-flight mass spectrometry (LDI-TOF MS) to adsorb and directly identify both cationic dyes without the need for an elution process. This approach demonstrated high sensitivity, high reproducibility, low background interference, and excellent salt tolerance. The limits of detection for MB and CV were 0.12 and 0.04 ng mL<sup>-1</sup>, respectively, representing improvements of 166-fold and 225-fold compared with using DP-COFs solely as a matrix. Recovery rates of both dyes in spiked industrial wastewater and lake water samples ranged from 81.4 to111.1% with RSDs of 1.9-6.3%. These results highlight the high reliability of the proposed method.</p>","PeriodicalId":462,"journal":{"name":"Analytical and Bioanalytical Chemistry","volume":" ","pages":"675-685"},"PeriodicalIF":3.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142793916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}