Se pu = Chinese journal of chromatography最新文献

{"title":"[Two-dimensional chiral metal-organic-framework nanosheets based on Co-BDC-NH₂ used as stationary phases for gas chromatography].","authors":"Mei-Fang Yang, Kang-Ni Zheng, Yi-Xing Long, Yi-Jie Li, Xue-Ping Wang, Jun-Hui Zhang, Li-Ming Yuan","doi":"10.3724/SP.J.1123.2024.06004","DOIUrl":"10.3724/SP.J.1123.2024.06004","url":null,"abstract":"<p><p>Two-dimensional metal-organic-framework (2D-MOF) materials have emerged as a new class of functional 2D material. Compared to bulk crystals, 2D-MOFs are easily derivatized, highly porous, and have sufficient active sites. While 2D-MOFs are of considerable research interest, they are also efficient candidates for multiple applications in a variety of fields owing to their numerous advantages. The ability to separate and analyze chiral compounds is greatly significant for progressing human society, and chromatographic separation is widely used in this regard owing to its high resolution and sensitivity. Few reports on the use of 2D-MOFs in chromatographic-separation applications currently exist, and those use gas chromatography to analyze and separate enantiomers are even rarer. Unsurprisingly, the development of novel stationary phases has become a popular topic in the chiral-chromatography field. In this study, 2D-MOF nanosheets (Co-BDC-NH<sub>2</sub>) were synthesized using a surfactant-assisted solvothermal method. The nanosheets were subsequently characterized by scanning electron microscopy and X-ray diffractometry. MOFs can be post-synthetically modified without affecting their frameworks, and such modifications can lead to the construction of chiral MOFs. Accordingly, Co-BDC-NH<sub>2</sub> was post-synthetically modified with glycyl-L-aspartic acid and glycyl-L-glutamic acid as chiral ligands to afford two chiral 2D-MOF nanosheets, namely Co-BDC-NH<sub>2</sub>-glycyl-L-aspartic acid and Co-BDC-NH<sub>2</sub>-glycyl-L-glutamic acid. These chiral 2D-MOF nanosheets were characterized by Fourier-transform infrared spectroscopy, circular dichroism, and thermogravimetric analysis. The two 2D-MOF nanosheet materials were used as chiral stationary phases in gas chromatography by coating them onto prepared capillary columns using a dynamic coating method; this process leaves a homogeneous coating layer on the inner wall of the column. Scanning electron microscopy confirmed that the two chiral columns had been successfully prepared. The columns were finally tested through gas-chromatography-separation experiments. Theoretical plates can be used to evaluate column efficiency. The Co-BDC-NH<sub>2</sub>-glycyl-L-aspartic acid and Co-BDC-NH<sub>2</sub>-glycyl-L-glutamic acid columns were determined to have 3538 and 3108 N/m theoretical plates, respectively, which implies that these columns are highly efficient. The McReynolds constant can be used to determine the polarity of the stationary phase in a chromatographic column; the two capillary columns exhibited McReynolds constants of 181 and 208, consistent with materials of medium polarity. The two chromatographic columns exhibited good abilities to resolve positional isomers and racemates (especially amino-acid derivatives), with seven racemates identified using the Co-BDC-NH<sub>2</sub>-glycyl-L-aspartic acid column, and eight identified using the Co-BDC-NH<sub>2</sub>-glycyl-L-glutamic acid colu","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 4","pages":"335-344"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966380/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143712711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Rapid and simultaneous determination of 11 ergot alkaloids in cereals and their products by ultra performance liquid chromatography-tandem mass spectrometry combined with Captiva EMR-Lipid column purification].","authors":"Bolin Liu, Dan Zhang, Zi-Wei Zhao, Ji-An Xie, Zi-Yue Zhan, Qi Zhang, Wei-Dong Li","doi":"10.3724/SP.J.1123.2024.02022","DOIUrl":"10.3724/SP.J.1123.2024.02022","url":null,"abstract":"<p><p>Ergot alkaloids (EAs) are mycotoxins produced by <i>Claviceps</i> and are present in cereals and their products; their residues pose significant threats to human health through food consumption, resulting in ergotism and sickness. Herein, a sensitive and rapid method for the determination of 11 EAs in cereals and their products using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) were developed. Eleven EAs were extracted with 20 mL acetonitrile-200 mg/L ammonium acetate solution (80∶20, v/v) for 15 min using the vortex shock method followed by 15 min of ultrasonication. The mixture was subsequently centrifuged at 10000 r/min for 10 min, and the supernatant was purified by a Captiva EMR-Lipid column. Target analytes were separated on an ACQUITY UPLC HSS T3 chromatography column (100 mm×3 mm, 1.8 μm) at a column temperature of 40 ℃ and a flow rate of 0.4 mL/min using an injection volume of 5 μL. Gradient elution was performed using 1 mmol/L ammonium acetate solution and acetonitrile as mobile phases. Data were collected in electrospray positive-ion (ESI⁺) and multi-reaction monitoring (MRM) modes, and quantified using matrix-matched standard curves. The 11 EAs exhibited good linearities in their linear ranges, with correlation coefficients (<i>r</i>²) of 0.9933-0.9999, with limits of detection (LODs) and limits of quantification (LOQs) of 0.002-0.2 and 0.006-0.6 μg/kg, respectively. Recoveries and relative standard deviations (RSDs) of the 11 EAs in matrix samples of wheat flour, coix seed, wheat flour products, and corn flour at low, medium, and high spiked levels were 80.1%-118% and 0.2%-13.3%, respectively. The established method was used to determine EAs in 240 wheat flour, 80 corn flour, 30 rice, and 30 coix seed samples, as well as 146 wheat flour products, with the detection rates of the 11 EAs of 0.57%-20.3%. A maximum total content of EAs of 56.7 μg/kg was recorded for a single sample. The sample pretreatment process used in this method is simple and fast, and the detection method is highly sensitive, with accurate and reliable results obtained. This method is suitable for simultaneously determining various EAs in cereals and their products. The results of this study provide valuable information for future EA risk-assessment studies.</p>","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 4","pages":"326-334"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966374/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143712705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Determination of eight organophosphate esters in animal-derived foods by ultra performance liquid chromatography-tandem mass spectrometry].","authors":"Yan Tang, Sheng Wen, Wen-Cheng Cao, Xiao Liu, Cheng-Lin Lei, Qing-Yun Cheng, Hai-Chuan Chen, Ling Liu, Xiao-Fang Liu, Yan Zhou","doi":"10.3724/SP.J.1123.2024.07010","DOIUrl":"10.3724/SP.J.1123.2024.07010","url":null,"abstract":"<p><p>Organophosphate esters (OPEs) are widely used as flame retardants in most regions, they adversely affect ecosystems and threaten human health. OPEs have attracted significant public attention because they are toxic and ubiquitously present in the environment. While China is among the world's largest users and producers of OPEs, limited data on the exposure of animal-derived foods to OPEs exist; consequently, a method for quantifying OPEs in animal-derived food samples is needed. In this study, a method was developed for the determination of eight OPEs, including triethyl phosphate (TEP), tripropyl phosphate (TPrP), tri-<i>n</i>-butyl phosphate (TnBP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), triphenyl phosphate (TPHP), and 2,2-bis(chloromethyl) trimethylene bis[bis(2-chloroethyl) phosphate] (V6), from twelve types of typical animal-derived foods by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The samples were purified using an HMR-Lipid SPE column. The effects of mobile phase A (water, 5 mmoL/L ammonium acetate aqueous solution, and 0.1% formic acid aqueous solution) and mobile phase B (methanol and acetonitrile), as well as the methanol/acetonitrile ratio on the separation and extraction efficiencies for the eight OPEs were investigated using one-way analysis. The results showed that optimal response values and peak shapes were obtained for the various compounds using 0.1% formic acid aqueous solution-acetonitrile system as the mobile phase. The following pretreatment procedure was used: A 0.5 g sample was accurately weighed and ultrasonically extracted with 5 mL of acetonitrile. The supernatant was collected after freezing and centrifugation, and cleaned-up was performed using an HMR-Lipid SPE column. The target analytes were analyzed using a Waters Acquity BEH C₁₈ column (100 mm×2.1 mm, 1.7 μm) and ESI⁺ MS conditions. Compound V6 was quantified by the external standard method, with the other seven compounds quantified using the internal standard method. The method exhibited linearity with <i>r</i>²≥0.9900, limits of detection (LODs) of 0.01-0.87 μg/kg, and limits of quantification (LOQs) of 0.02-2.62 μg/kg for the various substances. Spiked recoveries of the eight OPEs at three levels (2, 20, and 100 μg/kg) were in the range of 80.5%-117.8% and RSDs ≤ 14.8% (<i>n</i>=6). Twelve animal-derived foods (grass carp, bass, <i>Procambarus clarkii</i>, milk, milk powder, yogurt, pork, beef, chicken, duck meet, egg, and duck egg) were analyzed using the developed method. Compounds TnBP and TCIPP were detected at rates of 100%, and TEP, TCEP, TPHP, and TDCIPP at rates greater than 50%, while TPrP and V6 were not detected. The method has a simple-to-operate pre-treatment step, analyzes rapidly with good recoveries and precisions, and is suitable for rapidly analyzing and detecting eight OPEs in a","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 4","pages":"309-316"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966372/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143712661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Effects of nicotine exposure on endogenous metabolites in mouse brain based on metabolomics and mass spectrometry imaging].","authors":"Lu-Lu Guo, Chen Zhang, Yan-Jun Huang, Xing-Yu Liu, De-Shui Liu, Teng Long, Jin-Hao Sun, Shao-Feng Liu, Zhong-Hao Li, Jia-Zhong Wang, Jian Mao","doi":"10.3724/SP.J.1123.2024.10005","DOIUrl":"10.3724/SP.J.1123.2024.10005","url":null,"abstract":"<p><p>Nicotine, the principal alkaloid in tobacco, exhibits significant central nervous system activity and induces a wide array of physiological effects. In addition to its well-documented role in tobacco dependence, previous studies have suggested that nicotine also has diverse pharmacological properties. These include alleviating symptoms associated with Parkinson's disease, potentially reducing the risk of Alzheimer's disease, mitigating oxidative stress, as well as anti-inflammatory and anxiolytic effects. Neuroscientists frequently use an array of molecular biology techniques to elucidate the mechanisms responsible for the effects of nicotine on the central nervous system. However, disease onset is invariably accompanied by metabolic dysfunction, and organisms often exhibit complex and unpredictable responses to pharmacological stimuli. As a bioactive alkaloid with potent pharmacological properties, nicotine is able to cross the blood-brain barrier and induce brain-compound changes, which serves as the basis for its effects on the central nervous system. Consequently, examining the extensive impact of nicotine exposure on endogenous metabolites and metabolic pathways in the brain is an indispensable step toward providing a more robust foundation for understanding the complex physiological effects of nicotine. In this study, an ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) metabolomic-analysis method was established to systematically examine the effects of repeated nicotine exposure on endogenous metabolites in mouse brains. Two chromatographic systems fitted with Acquity UPLC BEH HILIC (150 mm×2.1 mm, 1.7 μm) and BEH C18 (150 mm×2.1 mm, 1.7 μm) columns were used to determine the nicotine present in samples. As a result, the established UHPLC-MS/MS method identified a total of 759 endogenous metabolites. Compared with the saline group, nicotine exposure resulted in 575 significantly different metabolites, with 434 metabolites down-regulated and 141 up-regulated. Further pathway-enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed that nicotine exposure primarily affects essential-amino-acid, lipid, nucleotide, carbohydrate, cofactor, and vitamin metabolism, as well as other amino-acid metabolic pathways in the brain. Although non-targeted metabolomics can simultaneously detect and analyze all small-molecule metabolites in an unbiased manner, accurately capturing metabolite changes in specific brain regions is challenging when dealing with complex brain-tissue systems. Targeting the aggregation of material bases and the delivery of precision treatment to certain brain regions is expected to be significant for the targeted therapy of central nervous system diseases. Airflow-assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI) was further used to directly visualize the nicotine-induced distributions and variations of differentially expressed me","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 4","pages":"363-371"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966373/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143712680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Determination of four oxidative stress biomarkers in human urine using solid-phase extraction coupled with ultra performance liquid chromatography-tandem mass spectrometry].","authors":"Zhuang-Zhuang Feng, Xiao Lin, De-Jun Bao, Xiao-Jian Hu, Hai-Jing Zhang, Ying Zhu, Xu Zhang","doi":"10.3724/SP.J.1123.2024.10003","DOIUrl":"10.3724/SP.J.1123.2024.10003","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Oxidative stress biomarkers are measurable biological indicators that reflect the balance between the production of reactive oxygen species (ROS) and the body's ability to neutralize them using antioxidants. Elevated oxidative stress is associated with a number of health effects. Herein, we report the development of a comprehensive and sensitive method for quantifying four typical oxidative stress biomarkers in human urine using solid-phase extraction (SPE) in conjunction with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The quantified biomarkers include L,L-dityrosine (diY), 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-hydroxyguanosine (8-OHG), and 4-hydroxynonenal mercapturic acid (HNEMA), which are markers of oxidative-stress-related damage in proteins, DNA, RNA, and lipids, respectively. To that end, we systematically optimized the MS parameters, SPE cartridge, and elution conditions of the method. Briefly, 0.2 mL of a urine sample was mixed with 0.8 mL of pure water, after which an internal-standard mixture was added. The four target analytes were enriched and purified using an HLB SPE cartridge. The diY and the other three compounds were eluted with 2% (volume fraction) methanol aqueous solution and methanol, respectively. The two groups of eluates containing different target analytes were separately injected onto an Acquity UPLC HSS T3 column (100 mm×2.1 mm, 1.8 μm) and gradient eluted using 0.05% (v/v) acetic acid aqueous solution and methanol. The target analytes were identified using both negative and positive electrospray ionization (ESI&lt;sup&gt;-&lt;/sup&gt; and ESI&lt;sup&gt;+&lt;/sup&gt;) and multiple reaction monitoring (MRM) modes, and quantified using stable-isotope-labeled internal standards. The four typical oxidative-stress biomarkers exhibited good linearities within the mass concentration range of 0.01-100 μg/L, with correlation coefficients ≥0.9998, and limits of detection (LODs) and limits of quantification (LOQs) of 7-18 and 22-60 ng/L, respectively. The spiked recoveries of the target analytes at three levels (5, 10 and 50 μg/L) were 103.0%-105.6%(8-OHdG), 100.8%-104.2%(8-OHG), 97.2%-100.2%(diY) and 96.9%-106.0%(HNEMA), with intra-day precisions of between 1.6% and 5.2%. Moderate-to-strong matrix effects of between 42% and 137% were observed for each target analyte. The target compounds exhibited weak matrix effects of 99%-102% (8-OHdG), 97%-98% (8-OHG), 97%-106% (diY), and 94%-110% (HNEMA) after adjustment using the stable-isotope-labeled internal-standard method. The developed method was used to determine the abovementioned four typical oxidative stress biomarkers in 40 urine samples. All target compounds were detected in human urine at rates of 100%, with mass concentrations of 0.52-14.40 μg/L, 2.75-38.15 μg/L, 8.92-82.28 μg/L, and 1.74-575.29 μg/L recorded for 8-OHdG, 8-OHG, diY, and HNEMA, respectively, along with median values of 2.89, 12.36, 37.66, and 96.92 μg/L, respectively. The developed method is","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 4","pages":"317-325"},"PeriodicalIF":0.0,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11966377/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143712664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Integrative transcriptomics-metabolomics approach to identify metabolic pathways regulated by glutamine synthetase activity].","authors":"Ting Ling, Jing Shi, Ting-Ze Feng, Shao-Jun Pei, Si-Yi Li, Hai-Long Piao","doi":"10.3724/SP.J.1123.2024.04003","DOIUrl":"10.3724/SP.J.1123.2024.04003","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Glutamine synthetase (GS), the only enzyme responsible for de novo glutamine synthesis, plays a significant role in cancer progression. As an example of the consequences of GS mutations, the R324C variant causes congenital glutamine deficiency, which results in brain abnormalities and neonatal death. However, the influence of GS-deficient mutations on cancer cells remains relatively unexplored. In this study, we investigated the effects of GS and GS-deficient mutations, including R324C and previously unreported K241R, which serve as models for GS inactivation. This study provided intriguing insights into the intricate relationship between GS mutations and cancer cell metabolism. Our findings strongly support recent studies that suggest GS deletion leads to the suppression of diverse signaling cascades associated with glutamine metabolism under glutamine-stripping conditions. The affected processes include DNA synthesis, the citric acid cycle, and reactive oxygen species (ROS) detoxification. This suppression originates from the inherent inability of cells to autonomously synthesize glutamine under glutamine-depleted conditions. As a key source of reduced nitrogen, glutamine is crucial for the formation of purine and pyrimidine bases, which are essential building blocks for DNA synthesis. Furthermore, the citric acid cycle is inhibited by the absence of negatively charged glutamate within the mitochondrial matrix, particularly when glutamine is scarce. This deficiency decreases the flux of &lt;i&gt;α&lt;/i&gt;-ketoglutarate (&lt;i&gt;α&lt;/i&gt;-KG), a principal driver of the citric acid cycle. Intermediate metabolites of the citric acid cycle directly or indirectly contribute to the generation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, a core component of redox homeostasis. Using the GS_R324C and GS_K241R mutants, we conducted an integrative transcriptomics and metabolomics analysis. The GS mutants with reduced activity activated multiple amino acid biosynthesis pathways, including arginine-proline, glycine-serine-threonine, and alanine-aspartate-glutamate metabolism. This intriguing behavior led us to hypothesize that despite hindrance of the citric acid cycle, abundant intracellular glutamate is redirected through alternative processes, including transamination. Simultaneously, key metabolic enzymes in the amino acid synthesis pathways, such as glutamic-oxaloacetic transaminase 1 (GOT1), glutamic-pyruvic transaminase 2 (GPT2), pyrroline-5-carboxylate reductase 1 (PYCR1), and phosphoserine aminotransferase 1 (PSAT1), exhibited increased mRNA levels. Additionally, GS deficiency appeared to upregulate the expression of glutamine transporters SLC38A2 and SLC1A5. Thus, restricting extracellular amino acids, such as glutamine, induces a stress response while promoting transcription or translation by a select group of genes, thereby facilitating cellular adaptation. However, similar to GS_WT, both GS_R324C and GS_K241R were modulated by glutamine t","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 3","pages":"207-219"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883535/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143569297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Determination of cycloxaprid and paichongding residues in foods of plant origin by ultra performance liquid chromatography-tandem mass spectrometry].","authors":"Jun-Jun Liu, Ju Li, Wan-Wan Yu, Ying Han, Xin-Xin Ma, Chun-Rui Zhan, Shi-Xiang Li, Hua-Wen Wu, Kui Hu, Jian-Chun Wan","doi":"10.3724/SP.J.1123.2024.04016","DOIUrl":"10.3724/SP.J.1123.2024.04016","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Neonicotinoid insecticides play an important role in the prevention and control of pests in crops, such as rice, wheat, corn, and vegetables, because of their broad spectrum, high efficiency, low toxicity, and low residue formation. However, their widespread use poses potential threats to the environment and human health. Cycloxaprid and paichongding are two new classes of neonicotinoid insecticides. The National Food Safety Standard Maximum Residue Limits for Pesticides in Foods (GB 2763) specifies the maximum residue limits for paichongding and cycloxaprid in rice, brown rice, wheat, and cabbage. However, the established limits are only temporary. In addition, no detection standards have yet been specified, and no relevant standards have been established in China. Therefore, establishing a method for analyzing cycloxaprid and paichongding residues in food is of particular importance. In this study, an optimized method was established to determine the residues of cycloxaprid and two noncorresponding isomers of paichongding in plant foods using ultra performance liquid chromatography-tandem mass spectrometry. The chromatographic conditions, matrix extraction methods for dried fruits and tea, and amounts of the purification materials C&lt;sub&gt;18&lt;/sub&gt;, PSA, GCB, and anhydrous magnesium sulfate were optimized. The pesticides were extracted using an acetonitrile solution and separated from water with the addition of sodium chloride. The samples were centrifuged at 5000 r/min for 5 min, after which 1.00 mL of the supernatant was purified using 150 mg of anhydrous magnesium sulfate, 25 mg of C&lt;sub&gt;18&lt;/sub&gt;, 25 mg of PSA, and 10 mg of GCB. Cycloxaprid and paichongding were separated on a ACQUITY UPLC BEH C&lt;sub&gt;18&lt;/sub&gt; chromatographic column (100 mm×2.1 mm, 1.7 μm) via gradient elution with 0.1% formic acid aqueous solution containing 5 mmol/L ammonium formate-acetonitrile as the mobile phase, and detected in electrospray positive ionization mode coupled with multiple-reaction monitoring (MRM) mode. Quantitative analysis was performed using an external standard method. Cycloxaprid and paichongding demonstrated good linear relationships within their respective concentration ranges, and the corresponding correlation coefficients were all above 0.99. The limits of detection (&lt;i&gt;S/N&lt;/i&gt;=3) and quantification were 0.05 μg/kg and 0.01 mg/kg, respectively, which meet the requirements specified in GB 2763-2021 and GB 2763.1-2022. The established method was used to validate the recoveries of cycloxaprid and paichongding spiked in foods of plant origin, such as paddy, brown rice, wheat, rice, peanut, raisin, cabbage, lettuce, green bean, tomato, potato, shiitake mushroom, apple, citrus, and tea substrates, at three levels. The spiked levels covered the limit levels specified in GB 2763-2021 and GB 2763.1-2022. The mean recoveries of the target substances added to the 15 substrates at concentrations of 1, 2, and 10 times the LOQ or the limit values specified i","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 3","pages":"261-268"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883517/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143569207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Open experiment: quantitative proteomics analysis of thyroid-cancer tissue slices using ultra-high performance liquid chromatography-tandem mass spectrometry].","authors":"Yi-Lan Li, Hui-Ming Yuan, Jing-Tian Cao, Yi-di Zheng, Lan Li, Pei-Feng Gao","doi":"10.3724/SP.J.1123.2024.07009","DOIUrl":"10.3724/SP.J.1123.2024.07009","url":null,"abstract":"<p><p>Open experiments play crucial roles in developing undergraduate students' practical abilities, innovative thinking, and teamwork. This open experiment is designed to use ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in proteomics, a frontier field, by quantitatively analyzing thyroid-cancer-tissue-slice samples. Various reagents are first screened for further study by evaluating their abilities to extract proteins. This approach aims to foster students' hands-on abilities and their scientific-research thinking. The liquid-chromatography method is subsequently optimized to enable deep-coverage of the proteome, thereby enhancing students' understanding of liquid chromatography and mass spectrometry. Paraffin-embedded thyroid-cancer-tissue slices are finally subjected to quantitative proteomic analysis, resulting in the identification of 33 differentially expressed proteins, thereby demonstrating their potential use in disease-typing applications. This open experiment integrates theoretical and experimental knowledge gained through instrumental analysis, analytical chemistry, and biochemistry, thereby imparting scientific research thinking and innovative spirit to undergraduates. It also provides students with opportunities to expand and solidify theoretical knowledge through hands-on instrumental operation and experiments, which helps to build a systematic knowledge framework and develop a comprehensive understanding of relevant fields. Moreover, it stimulates undergraduate interest in scientific research, cultivates innovative thinking, and fosters team cooperation.</p>","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 3","pages":"275-282"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883525/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143569303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Determination of trace anions in G2-grade phosphoric acid using two-dimensional ion-exclusion-ion-exchange chromatography with valve-switching technology].","authors":"Jia-Ding Wang, Gao Tang, Yan Lu, Heng-Jun Lu, Tao Ye","doi":"10.3724/SP.J.1123.2024.04010","DOIUrl":"10.3724/SP.J.1123.2024.04010","url":null,"abstract":"<p><p>This study established a method for determining trace anions in G2-grade phosphoric acid under ultra-clean conditions that used two-dimensional ion-exclusion-ion-exchange chromatography coupled with valve-switching technology. The optimal flow rate of ultrapure water through the ion-exclusion column in the first dimension was determined to be 0.5 mL/min through comparative experiments. The valve-switching window was optimized to minimize enriching PO₄^3- on the anion-enrichment column and reduce interference from the phosphoric-acid matrix. The use of external water mode for the suppressor led to lower baseline noise, and optimizing the elution program of the second dimension enabled target trace anions to be well separated, thereby avoiding the risk of a false positive for NO^3-. The anions of Cl^-, Br^-, NO^3-, and SO₄^2- exhibited good linearities within the 0.5-20 μg/kg, with correlation coefficients ≥0.999. The limits of detection (LODs) and quantification (LOQs) were 0.09-0.29 μg/kg and 0.29-0.97 μg/kg, respectively. The spiked recoveries of each anion at four spiked levels ranged from 91.7% to 103.6%, with RSDs of 0.1%-4.9%. The developed method demonstrated excellent stability through repeated injections, and low detection limits; it is highly precise and accurate, and meets the detection requirements for trace anions in G2-grade phosphoric acid. Additionally, retention-time comparisons with single standard substances led to the discovery of other phosphorus-related anions and anion clusters, such as hypophosphite (HPO₃^-) and hexametaphosphate (PO₃^-)₆, in G2-grade phosphoric acid, in addition to conventional anions. This finding is theoretically and practically significant for the future development of purification processes for higher-purity phosphoric acid.</p>","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 3","pages":"237-244"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883536/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143569241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Determination of glucose in exhaled breath and saliva by ion chromatography].","authors":"Jian-Jun Xu, Chao-Yan Lou, Yan-Hong Zhuo, Yan Zhu","doi":"10.3724/SP.J.1123.2024.06011","DOIUrl":"10.3724/SP.J.1123.2024.06011","url":null,"abstract":"<p><p>A novel noninasive method was developed for determining glucose levels in human exhaled breath and saliva using ion chromatography. This innovative approach involves collecting exhaled breath and saliva samples using a self-designed condensation device and non-stimulative method to ensure minimal participant discomfort. The glucose contents in both exhaled breath condensate (EBC) and saliva were analyzed using ion chromatography, which is highly sensitive and specific. The experimental conditions were optimized, including a condensation temperature of -14 ℃ and an expiratory flow of 15 L/min. A Dionex CarboPac MA1 ion chromatography column (250 mm×4 mm) was used to separate glucose, with the column temperature maintained at 30 ℃. Sodium hydroxide solution (0.8 mol/L) with a pump flow rate of 0.4 mL/min was used as the mobile phase for ion chromatography. Under these conditions, glucose exhibited a good linear relationship in the range of 0.01-20 mg/L, with a correlation coefficient of 0.9999, along with limits of detection (LOD) and quantification (LOQ) of 2.1 and 7.0 μg/L, respectively. The intra- and inter-day precisions of glucose content in exhaled breath and saliva samples of ≤7.5% (<i>n</i>=5) and ≤8.4% (<i>n</i>=5), respectively. The results reveal that the glucose levels in exhaled breath and saliva are strongly correlated with blood glucose levels. The method was validated by measuring the glucose contents of exhaled breath and saliva from six diabetic patients and six healthy subjects. Little variation in the glucose contents of the exhaled breath of the two groups was observed under fasting states. However, the exhaled breath of the diabetic patients exhibited significantly higher (by factors of 6-80) glucose contents (48.4-140.0 ng/L) than those of healthy subjects (1.7-7.9 ng/L) 1 h after glucose ingestion. Saliva samples from fasting diabetic patients contained 1.2-5.0-times more glucose contents (87.6-158 mg/L) than those of healthy subjects (31.6-70.9 mg/L). In addition, the saliva of the diabetic patients exhibited glucose contents (136-257 mg/L) that were 1.8-7.7-times higher than those of the healthy subjects (33.1-75.2 mg/L) 2 h after glucose ingestion. The developed method provides a simple, precise, and non-invasive means of detecting glucose contents in a manner that does not harm the human body; hence, it is a promising non-invasive metabolic-monitoring tool. This study opens new avenues for the development of innovative technologies for monitoring glucose and other biomarkers, which is expected to greatly enhance metabolic-study accuracy and ease, particularly in the context of managing diabetes and other metabolic disorders.</p>","PeriodicalId":101336,"journal":{"name":"Se pu = Chinese journal of chromatography","volume":"43 3","pages":"245-251"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11883544/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143569265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}