Journal of separation science最新文献

{"title":"Losartan API and Nitrosamines Impurities-Stability Profile Investigation Using HPLC, LC-MS, and In Silico Assessment.","authors":"Paulo Roberto Rodrigues Martini, Lilian Fanfa Machioli, Bruno Pereira Dos Santos, Tiago Franco de Oliveira, Fávero Reisdorfer Paula, Clésio Soldateli Paim, Andreas Sebastian Loureiro Mendez","doi":"10.1002/jssc.70438","DOIUrl":"https://doi.org/10.1002/jssc.70438","url":null,"abstract":"<p><p>Nitrosamines are potent genotoxic impurities with well reported mutagenic and carcinogenic effects. Their presence has been detected in several pharmaceutical products among them losartan, an angiotensin II receptor blocker. Considering the risks already reported for these impurities, the present study aimed to investigate the influence of four common nitrosamines-N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosodiisopropylamine (NDIPA), and N-nitrosodibutylamine (NDBA)-in the stability profile of losartan API. Quantitative assay was conducted through HPLC and LC-MS, with focus on monitoring degradation rate and degradation products under influence of nitrosamines. Predictive data by in silico investigation employing Zeneth Nexus and Spartan were simultaneously studied, considering degradation products, fragmentation pathway and nitrosamines reactivity. The drug residual content showed variability depending on the nitrosamine evaluated and the stressing condition applied. From photolysis, for example the residual content ranged 80%-90%, with a greater decomposition in samples containing nitrosamines. A greater decomposition was also observed in oxidative degradation, with exception for samples containing NDMA. Acid and basic media caused a significant decomposition, with the residual losartan content in a range of 41%-52% and 28%-51%, respectively. From LC-MS analyzes, these impurities were mostly not detected in the degraded samples, suggesting their consumption during the reaction due to their reactivity. A protective effect from nitrosamines can be also reported possibly due to their reactivity against the stressing factor. Seven degradation products were structurally proposed by LC-MS at m/z 449, m/z 447, m/z 366, m/z 338, m/z 274, m/z 391, and m/z 341, some of them predicted computationally by Zeneth.</p>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 5","pages":"e70438"},"PeriodicalIF":2.8,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147856577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrasensitive Determination of Artificial Sweeteners in Environmental Water Samples Through Capillary Electrophoresis Coupled With Capacitively Coupled Contactless Conductivity Detection","authors":"Yu-Ming Chou,&nbsp;Ming-Mu Hsieh,&nbsp;Wen Ting Yeh","doi":"10.1002/jssc.70412","DOIUrl":"10.1002/jssc.70412","url":null,"abstract":"<div>\u0000 \u0000 <p>A dual-enrichment method based on efficient sample cleanup offline ion-pair ultrasonic surfactant-assisted dispersive liquid–liquid microextraction coupled with efficient sample stacking through online field-amplified sample stacking was devised for the concurrent determination of three artificial sweeteners (acesulfame potassium, saccharin, and cyclamate) using capillary electrophoresis (CE) coupled with capacitively coupled contactless conductivity detection. Various parameters that affected the CE separation performance and the enrichment efficiency of ion-pair ultrasonic surfactant assisted dispersive liquid–liquid microextraction and field-amplified sample stacking were optimized, and excellent CE separation was attained within 20 min. The optimal ion-pair ultrasonic surfactant-assisted dispersive liquid–liquid microextraction method used 240 µL of chlorobenzene as the extraction solvent, 125 µM N-methyl-N, N-dioctyloctan-1- ammonium chloride as the surfactant, and a pH of 7. Sample stacking was achieved by field amplified sample stacking in a 65 mM butyric acid buffer (pH 2.95), and the signal was detected by capacitively coupled contactless conductivity detection (2 Vpp, 200 kHz). Under the optimized conditions, the proposed method achieved enrichment factors ranging from 3158 to 3261. The linear concentration range was found to be 0.3–30 nM (<i>r</i> &gt; 0.9993). The limits of detection for the three artificial sweeteners were in the range of 0.092–0.095 nM. Good precision was verified by the low relative standard deviations for migration times (3.0%) and peak areas (9.0%). The method was successfully applied to spiked environmental water samples. The relative errors for accuracy ranged from −3.4% to 7.5% for lake water, −8.8% to −0.3% for river water, and −6.8% to 9.6% for groundwater. Consequently, this method represents an efficient, rapid, and low-cost technique for extracting and determining artificial sweeteners in environmental water matrices.</p>\u0000 </div>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147674470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of Novel Epimer Metabolites of Sweroside in Rats With Liquid Chromatography/Time of Flight Mass Spectrometry Combined With Picolinoyl Derivatization","authors":"Yaqi Xu,&nbsp;Shuhan Tang,&nbsp;Yidan Sun,&nbsp;Hao Li,&nbsp;Yige Wang,&nbsp;Xintong Li,&nbsp;Minyue Zhang,&nbsp;Rong Ma,&nbsp;Xianna Li,&nbsp;Hongying Xu,&nbsp;Xuexi Wang,&nbsp;Ying Wang,&nbsp;Hailong Zhang,&nbsp;Zhigang Wang","doi":"10.1002/jssc.70413","DOIUrl":"10.1002/jssc.70413","url":null,"abstract":"<div>\u0000 \u0000 <p>Sweroside (SRD) is an important iridoid compound that exhibits various pharmacological and biological activities. However, it has been suggested that the remarkable pharmacological activity is due to the metabolites of the iridoids rather than themselves. Therefore, it is crucial to identify the actual bioactive metabolites of iridoids in vivo. The in vivo metabolites of SRD were analyzed using ultra-high performance liquid chromatography-time of flight-mass spectrometry (UHPLC-TOF-MS) and picolinoyl derivatization. Two major exosomatic SRD metabolites derived from human intestinal bacteria, epinaucledal and naucledal, were incubated with liver microsomes, which were reduced to swerosimetabolin A (SMA) and a novel metabolite named swerosimetabolin B (SMB), respectively. Pharmacokinetic studies of SRD were performed Wistar rats. The mass detection sensitivity of the epimer metabolites SMA and SMB using UHPLC-TOF-MS increased apparently following picolinoyl derivatization. These two metabolites distinctly existed within the rat plasma after gavage administration of SRD. The concentrations of SMA and SMB in plasma were analyzed using UHPLC-TOF-MS in positive ion mode, with 3,4-dihydro-5-(hydroxymethyl) isochroman-1-one as an endogenous reference. SMA and SMB achieved maximal mean plasma concentrations of 61.98 ± 8.6 ng/mL (within 2 h) and 42.64 ± 9.6 ng/mL (within 4 h), respectively, following gavage administration of 20 mg/kg SRD. The area under the concentration-time curve for SMB was 1.5-fold higher than that of SMA. Furthermore, the SRD metabolism to the sulfate of SMA and SMB was deduced. This study reports the metabolism of SRD into SMA and SMB in vivo. These metabolites demonstrated high pharmacological activity, which can help clarify the effects of SRD.</p>\u0000 </div>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147674533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultra-High-Performance Liquid Chromatography-High-Resolution Mass Spectrometry Coupled with Multivariate Analysis Deciphers the Dynamic Transformation of Ginsenosides and the Enhancement of Antioxidant Activity in Nine-Steaming-Nine-Drying Black Ginseng","authors":"Hao Lu,&nbsp;Yu Geng,&nbsp;Ye Jing,&nbsp;Sixuan Wang,&nbsp;Wenyi Gao,&nbsp;Guangzhi Cai,&nbsp;Yunlong Guo,&nbsp;Jiyu Gong","doi":"10.1002/jssc.70393","DOIUrl":"10.1002/jssc.70393","url":null,"abstract":"<div>\u0000 \u0000 <p>Black ginseng, produced through the traditional nine-steaming–nine-drying process, exhibits enhanced pharmacological activity compared with unprocessed ginseng. This study investigated the dynamic changes in ginsenoside composition and antioxidant activity during steam-drying using a non-targeted metabolomics approach based on ultra-high-performance liquid chromatography-mass spectrometry. A total of 73 ginsenosides were identified, among which 47 differential markers were screened by principal component analysis and partial least squares discriminant analysis. The relative quantification of 29 key markers revealed distinct transformation patterns of ginsenosides during processing. Antioxidant capacities, evaluated by 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS), and Ferric Reducing Ability of Plasma (FRAP) assays, showed trends consistent with changes in total ginsenoside content. The results elucidate the transformation pathways of major ginsenosides during steam-drying and provide a theoretical basis for process optimization and quality control of black ginseng-derived products.</p>\u0000 </div>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147674522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unraveling the Oligomer-specific Uptake Dynamics of PEG600 With 9–18 Subunits in HepG2 Cells by Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry Coupled With Ammonium Adduct Strategy to Enhance Sensitivity","authors":"Jiye Tian,&nbsp;Xinyue Zheng,&nbsp;Zihan Tang,&nbsp;Chunpeng Feng,&nbsp;Meichen Liu,&nbsp;Ning Zhang,&nbsp;Hongyu Xue,&nbsp;Jiansong You,&nbsp;Lei Yin,&nbsp;Meiyun Shi","doi":"10.1002/jssc.70404","DOIUrl":"10.1002/jssc.70404","url":null,"abstract":"<div>\u0000 \u0000 <p>Polyethylene glycol (PEG) has emerged as a predominant synthetic polymer in contemporary drug delivery systems due to its unique physicochemical properties and versatile functionalization capabilities. Deciphering chain-length-dependent biosafety and cellular uptake profiles of PEG polymers is vital for optimizing nanomedicine formulations. We established an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) methodology employing ammonium adduction for multiplex quantification of PEG600 oligomers (<i>n</i> = 9–18) in human hepatocellular carcinoma (HepG2) hepatocytes. The method demonstrated linear response (<i>R</i>² &gt; 0.99) across 10–1000 ng/mL for PEG600 oligomers (<i>n</i> = 9–18). PEG600 oligomers (<i>n</i> = 9–18) internalization in HepG2 cells was quantified by the validated UHPLC-MS/MS method. PEG600 polymers with 9–18 subunits could be absorbed into HepG2 cells with a small quantity (less than 0.04%). The cytotoxicity study suggested that the half-maximal inhibitory concentration of PEG600 on HepG2 cells is 31.42 mg/mL. PEG600 oligomers demonstrated negligible anti-proliferative effects in HepG2 hepatocytes. This study could provide analytical techniques and critical reference data for cytotoxicity and whole cellular uptake profiles of PEG600 polymers with 9–18 subunits in HepG2 cells. This work establishes an analytical framework for assessing the cytotoxicity and cellular uptake kinetics of PEG600 oligomers (<i>n</i> = 9–18) in HepG2 cells.</p>\u0000 </div>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147623286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction and Analysis of Quality Markers for Hedysari Radix Using Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry, Network Pharmacology, Molecular Dynamics, and Chemometrics","authors":"Xudong Luo,&nbsp;Xinrong Li,&nbsp;Peng Qi,&nbsp;Chengyi Li","doi":"10.1002/jssc.70410","DOIUrl":"10.1002/jssc.70410","url":null,"abstract":"<div>\u0000 \u0000 <p>To establish a scientific and reliable quality evaluation method for Hedysari Radix (HR), this study investigated changes in chemical components before and after the “Rubbing strip” (RS) was processed based on Quality Marker (Q-Marker) theory. By integrating ultra-high-performance liquid chromatography-tandem mass spectrometry quantitative analysis, network pharmacology, molecular dynamics, and chemometrics to elucidate compositional variations and predict potential quality markers systematically. Results showed significantly increased contents of formononetin, calycosin, liquiritigenin, and γ-aminobutyric acid after the RS was processed, while the contents of ononin, calycosin-7-glucoside, and vanillic acid were reduced. These findings suggest that RS processing may facilitate the transformation of isoflavone glycosides into aglycones through mechanochemical effects. Network pharmacology analysis further identified 10 immune-related compounds, including medicarpin, calycosin-7-glucoside, calycosin, ononin, and formononetin, as potential quality markers. Using chemometric methods such as hierarchical cluster analysis, principal component analysis, and Orthogonal partial least-squares discriminant analysis, robust discrimination models distinguishing RS from “Non-rubbing strip” samples were successfully developed based on the identified Q-Marker. This study, integrating chemical profiling and bioinformatics approaches, identified and predicted potential Q-Markers for HR, providing theoretical and methodological support for establishing a robust and scientifically quality evaluation system for HR.</p>\u0000 </div>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147623280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating Ultra-High-Performance Liquid Chromatography-Photodiode Array Detector Coupled to Quadrupole Time-of-Flight Mass Spectrometry, Network Pharmacology, and Antidepressant Effects to Determine the Optimal Cultivation Years for Paeonia lactiflora Roots","authors":"Zhao Jin,&nbsp;Hao-Qi He,&nbsp;Li-Ping Zhang,&nbsp;Meng Yu,&nbsp;Zhong-Mei Zou","doi":"10.1002/jssc.70408","DOIUrl":"10.1002/jssc.70408","url":null,"abstract":"<div>\u0000 \u0000 <p>Paeoniae Radix Alba (called Baishao in China, BS), the dried root of <i>Paeonia lactiflora</i> Pall., is a key ingredient in classic Chinese medicine formulas used to treat depression. This study aimed to optimize its cultivation period by integrating analysis of chemical constituents and antidepressant effects. Chemical profiling of 5-year-old roots (BS_5Year) using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry led to the identification of 44 major constituents. Network pharmacology analysis predicted that 12 primary constituents, five monoterpenes (oxypaeoniflorin, albiflorin, paeoniflorin, 6'-<i>O</i>-galloylpaeoniflorin, and benzoylpaeoniflorin) and seven polyphenols (gallic acid, methyl gallate, catechin, 1,3,6-trigalloylglucose, 1,2,3,6-tetragalloylglucose, benzoic acid, and 1,2,3,4,6-pentagalloylglucose) were key contributors to the antidepressant effects. Quantitative analysis by ultra-high-performance liquid chromatography-diode array detection showed that the content of these active constituents in BS_5Year was comparable to that in 4-year-old roots (BS_4Year). Behavioral tests (forced swimming and tail suspension) confirmed no significant difference in antidepressant efficacy between the two groups. These findings indicate that a 4-year growth period is sufficient to achieve the desired quality, thus establishing it as the optimal harvest time. Therefore, this study not only guides the cultivation of <i>P. lactiflora</i> but also highlights the importance of integrating chemical and bioactivity data to determine the optimal harvest time for herbal medicines.</p>\u0000 </div>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147623307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clean version Comparative Chromatographic Separation of Free Radicals From Natural Products Using Green Organic Solvents","authors":"Chuang Liu,&nbsp;Ruihan Liu,&nbsp;Fei Gao,&nbsp;Yu Zhang,&nbsp;Jun Dang,&nbsp;Fei Fang","doi":"10.1002/jssc.70407","DOIUrl":"10.1002/jssc.70407","url":null,"abstract":"<div>\u0000 \u0000 <p>A well-designed liquid chromatographic strategy is essential for the reliable characterization and preparative isolation of natural products (NPs). In this study, an integrated “medium-pressure pretreatment followed by 0.2% formic acid (FA) H₂O-EtOH high-pressure purification” strategy was employed to achieve the efficient separation of active compounds in <i>Ribes himalense</i>. Guided by the online high-performance liquid chromatography-DPPH assay, Fr111 and Fr112 were recovered from the <i>R. himalense</i> extract by polyamide- and Spherical C18-medium-pressure liquid chromatography. The chromatographic behavior of these fractions was comparatively examined under hydrophilic and reversed-phase conditions using three commonly employed aqueous-organic mobile phases, namely 0.2% FA H₂O-ACN, 0.2% FA H₂O-MeOH, and 0.2% FA H₂O-EtOH. Under the investigated experimental conditions, the 0.2% FA H₂O-EtOH system exhibited improved peak resolution and separation selectivity for both fractions relative to the other mobile phases. Ultimately, four free radical inhibitors (&gt;95% purity) with flavonoids as the parent nucleus were obtained from Fr111 and Fr112. Their significant in vitro free radical scavenging activity was validated using the DPPH and ABTS assays. In conclusion, the 0.2% FA H₂O-EtOH system delivered favorable chromatographic performance while reducing solvent toxicity, demonstrating promise for efficient and greener preparative workflows. The proposed strategy offers a practical and scalable approach for the targeted isolation of structurally similar bioactive compounds from NPs in the foreseeable future.</p>\u0000 </div>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147623321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of an LC-Benchtop Nuclear Magnetic Resonance at 125 MHz for Use in Stop-Flow Gradient-Based Separations of Pharmaceutical Compounds.","authors":"Noah R C Menard, Tyler M Ozvat, John Frost, John Price, Masayuki Nishimura, Jonathan T Ferguson, Gilbert D Vial, Scott Kuzdzal, Toshiya Matsubara, Kevin A Schug","doi":"10.1002/jssc.70417","DOIUrl":"https://doi.org/10.1002/jssc.70417","url":null,"abstract":"<p><p>The development of a high-performance liquid chromatography system with a benchtop ¹H nuclear magnetic resonance (NMR) spectrometer for use in stop-flow mode with a gradient separation is described for the first time. Advancements in permanent magnet-based benchtop NMR technology have resulted in a field strength of 125 MHz for increased sensitivity with the use of an integrated flow cell. The size and accessibility of benchtop NMRs can allow easier access to NMR for many laboratories. Development was focused on analytical scale instrumentation with concentrations and injection volumes commonly seen in this scale. A combination of pharmaceuticals, specifically acetaminophen, caffeine, warfarin, and ibuprofen, which present a wide profile of different NMR spectra, was examined. Separations and subsequent NMR data collection were performed successfully in multiple common protonated solvents, as opposed to high volumes of costly deuterated solvents, to show the versatility of this new application. Each separated compound presented was successfully analyzed in online stop-flow mode within a single run and was repeated across solvent mixtures. All compounds were detected within a minimum signal-to-noise (SNR) ≥ 3 post-separation after NMR spectra were processed in MestReNova. These were then compared to individual samples tested in typical deuterated solvents for ¹H NMR to confirm the success of this approach.</p>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":"e70417"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147690698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the Mechanism of Component Evolution and Viscosity Change Based on Temperature Differences in In-Situ Combustion of Paraffinic Heavy Oil.","authors":"Fajun Guo, Hong Chen, Yuying Li, Qingqiao Zeng, Yong Guo, Xiaojing Liang, Xusheng Wang","doi":"10.1002/jssc.70423","DOIUrl":"https://doi.org/10.1002/jssc.70423","url":null,"abstract":"<p><p>This study investigated the relationship between component evolution and viscosity reduction in the Menggulin paraffinic crude oil reservoir under reservoir conditions using gas chromatography-mass spectrometry and viscosity measurements at reservoir temperature (37.2°C). Results show stage-dependent compositional transformation: in 250-400°C medium-temperature oxidation, C₆-C₉ components are fully combusted, with displaced oil dominated by residual alkanes and oxygenates, yielding limited viscosity reduction. Above 400°C (high-temperature cracking), long-chain n-alkanes undergo β-scission to generate abundant C₁₀-C₂₅+ long-chain α-olefins, which reduce viscosity via physical dilution and polar interaction with wax crystals/resins. Specifically, 10% addition of 500°C-displaced oil lowers the original 853 mPa·s viscosity to ∼200 mPa·s (88% reduction), outperforming 250°C-displaced oil (needing >25% addition). This study reveals that Menggulin crude exhibits a unique olefin-dominated evolution, identifies long-chain α-olefins as the signature products of paraffinic crude during in-situ combustion (ISC), verifies temperatures above 400°C as the optimal temperature window, and thus provides a scientific basis for the optimization of ISC in similar reservoirs.</p>","PeriodicalId":17098,"journal":{"name":"Journal of separation science","volume":"49 4","pages":"e70423"},"PeriodicalIF":2.8,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147774609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}