An ultrahigh-performance liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of lactoferrin in camel milk based on the signature peptide. The camel lactoferrin was purified by heparin affinity chromatography and then used to screen tryptic signature peptides. The signature peptide was selected on the basis of sequence database search and identified from the tryptic hydrolysates of purified camel lactoferrin by ultrahigh-performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry. The pretreatment procedures included the addition of isotope-labeled winged peptide and the disposal of lipids and caseins followed by an enzymatic digestion with trypsin. Analytes were separated on an Acquity UPLC BEH 300 C18 column and then detected on a triple-quadrupole mass spectrometer in 7 min. The limits of detection and quantification were 3.8 mg kg⁻¹ and 11 mg kg⁻¹, respectively. The recoveries ranged from 74.5% to 103.6%, with relative standard deviations below 7.7%. The validated method was applied to determine the lactoferrin in ten samples collected from Xinjiang Province.

The study determined 19 elements in peanuts of different regions in China by ICP-MS, and explored a method of identifying peanut origin by multi-element analysis.

Trans fatty acids (TFAs) pose significant health risks, including cardiovascular disease and metabolic disorders. However, the lack of high-resolution, high-sensitivity, and high-throughput quantitative methods for TFA analysis has led to fragmented data on TFA content in edible oils, which constrains research on the quality assessment of edible oils. In this study, we developed a high-resolution and high-sensitivity gas chromatography-mass spectrometry method to simultaneously determine 23 TFA isomers. The method validation demonstrated good sensitivity, linearity, accuracy, and precision. Based on the proposed method, we analyzed 170 samples of 11 common edible oils, establishing a comprehensive TFA profile for each type. Ruminant fats (beef tallow, mutton tallow, butter) had high TFA levels (0.8–4.8 g/100 g), dominated by vaccenic acid (C18:1 t11) and conjugated linoleic acid, while vegetable oils (soybean, corn, peanut and sesame oil) exhibited lower concentrations (0.5–2.2 g/100 g), especially monounsaturated TFAs. Particularly, soybean oil was rich in C18:3 isomers, while shortening presented the closest similarity to sesame oil. Cluster analysis distinguished oils by TFA composition, highlighting low-TFA clusters (sunflower oil, pork lard, cream). In conclusion, the high-resolution, high-sensitivity, and high-throughput TFA quantification method developed in this study provides technical support for establishing characteristic TFA profiles in edible oils, while offering data support to further quality assessment.

Chlorothalonil and its toxic metabolite, 4-hydroxy-chlorothalonil, pose significant environmental and health risks. However, their simultaneous and accurate detection remains challenging due to their differing ionization efficiencies in mass spectrometry and the interference caused by enzymatic reactions in sulfur-rich vegetables. This study developed a UHPLC-MS/MS method for simultaneous detection of chlorothalonil and 4-hydroxy-chlorothalonil, using an atmospheric pressure chemical ionization (APCI) source, optimizing the probe temperature to 600 °C and a set of optimal chromatography parameters. A low-temperature and acidification synergistic enzyme inhibition strategy was developed, involving refrigerating samples and extraction reagents, acidifying with citric acid before sample homogenization, and extracting with formic acid/acetonitrile, significantly improving chlorothalonil recovery. Method validation demonstrated limits of detection (LOD) and quantification (LOQ) of 0.003 mg/kg and 0.01 mg/kg, respectively, with recoveries of 76.5–91.1% for chlorothalonil and 87.6–96.7% for 4-hydroxy-chlorothalonil. The method was successfully applied in monitoring the residue risks in sulfur-rich vegetables.

Trans fatty acids (TFAs) pose significant health risks, including cardiovascular disease and metabolic disorders. However, accurate TFA analysis remains challenging due to complex isomerism, trace concentrations, and methodological limitations in Flame Ionization Detector. In this study, we developed a high-sensitive and high-throughput GC-MS method to simultaneously determine 23 TFA isomers. The method validation demonstrated good sensitivity, linearity, accuracy, and precision. Based on the proposed method, we analyzed 170 edible oil samples and systematically compared 11 common edible oils, establishing a comprehensive TFA profile for each type. Ruminant fats (beef tallow, mutton tallow, butter) had high TFA levels (0.8-4.8 g/100g), dominated by vaccenic acid (C18:1 t11) and CLA, while vegetable oils (soybean, Corn, peanut and sesame oil) exhibited lower concentrations (0.5–2.2 g/100g), especially TMUFA. Particularly, soybean oil was rich in C18:3 isomers, while shortening presented the closest similarity to sesame oil. Cluster analysis distinguished oils by TFA composition, highlighting low-TFA clusters (sunflower oil, pork lard, cream). In conclusion, our study provides technical methods and data support for the quality safety evaluation and risk assessment of edible oils.