最新刊期
卷 43 ， 期 4 ， 2024
- 摘要：The chemical components of the Jixueteng formula extract were qualitatively identified using ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry（UPLC-Q-TOF-MS/MS） technology. A Waters ACQUITY UPLC BEH C18 chromatographic column（100 mm×2.1 mm，1.7 μm） was employed，with a mobile phase consisting of 0.1% formic acid solution-acetonitrile using a gradient elution. The flow rate was set at 0.3 mL/min and the column temperature at 30 ℃. MS analysis was based on electrospray ion source with positive and negative ion mode scanning. The identification of compounds was conducted through the mass spectrometry database，compound fragmentation patterns，and relevant literature. In this experiment，a total of 82 compounds were identified，mainly including flavonoids，phenylpropanoids，and terpenoids. Among them，there were 22 types of flavonoids，24 types of phenylpropanoids，25 types of terpenoids，4 types of phenolic acids，6 types of steroids，and 1 type of amino acids. Additionally，10 new chemical components were discovered for the first time when the herbal ingredients were combined to form a compound. UPLC-Q-TOF-MS/MS technology provides a convenient，fast，and accurate method for identifying chemical components in the Jixueteng formula extract. The identified chemical constituents can cover the main active ingredients of the herbal compound，providing experimental evidence and theoretical foundation for quality standardization and pharmacological research of the compound.关键词：UPLC-Q-TOF-MS/MS;Jixueteng formula extract;chemical constituents;fragmentation pattern
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发布时间：2024-04-18 - 摘要：In the practice of forensic science，it is often necessary to accurately determine the identity of the test material and the sample document by analyzing the composition of the ink in the document.Hyperspectral imaging technology combined with machine learning was used to distinguish the types of inkjet printing inks. Hyperspectral images of documents printed with 4 colors（black，blue，magenta and yellow） of 14 sets of different brands and models were collected in the range of 400-1 000 nm，and spectral data of 56 samples were extracted.Use the uniform manifold approximation and projection（UMAP） and T-distributed stochastic neighbor embedding（t-SNE） two algorithms for hyperspectral data dimension reduction processing inkjet printing ink，and then establish extreme gradient boosting（XGBoost），light gradient boosting machine（LightGBM）and support vector machine（SVM），determine the test set and training set in the ratio of 1∶4，and classify the original data and the data after dimensionality reduction respectively.The experimental results show that UMAP dimension reduction algorithm combined with SVM model has the best effect on the classification of inkjet printing inks. The classification accuracy of black ink samples is about 90%，and the classification accuracy of other color ink samples is 100%.This study provides a new，non-destructive and accurate identification method for inkjet printing documents.关键词：hyperspectral imaging technology;inkjet printing ink;dimensionality reduction algorithm;classification model
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发布时间：2024-04-18 - 摘要：Simple and rapid sample pretreatment technology is needed for the surface-enhanced Raman scattering（SERS） detection of trace organic components in transformer oil. In this paper，the dealkaline lignin/diatomite（DAL/DE） hydrogel was prepared by free radical polymerization using dealkaline lignin（DAL） and diatomite（DE） as raw materials，adding 2.5% acrylic acid（AA），0.75% ammonium persulphate（APS） and 0.25% N’N-methylene bisacrylamide（MBA）. The adsorption propertiesof hydrogel to 1，2，3-benzotriazole（BTA） in transformer oil were investigated by high-performance liquid chromatography. Then SERS combined with solid phase extraction was used to detect BTA in transformer oil. The results showed that 0.6 g DAL/DE hydrogel as solid phase extraction filler water as activator，and the transformer oil sample of BTA with 1-fold dilution，the eluent was 1 mL acetic acid. In the content range of 1-500 mg/kg BTA，the peak strength at 776 cm-1 shows a good linear relationship with the content of BTA，and the detection limit was as low as 0.28 mg/kg.关键词：transformer oil;1，2，3-benzotriazole;lignin;hydrogel;solid phase extraction;surface-enhanced Raman spectroscopy
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发布时间：2024-04-18 - 摘要：The chemical composition of Fu Fang Xiang Zuo Shui was rapidly identified and classified using ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry（UPLC-Q-TOF MS） technology. The pretreatment method and instrument conditions of compound Fu Fang Xiang Zuo Shui were optimized by chromatographic peak response degree and separation effect. An Agilent Phe Hex column（150 mm×2.1 mm，1.9 μm） was employed with a mobile phase consisting of 0.1% formic acid aqueous solution and acetonitrile，using gradient elution at a flow rate of 0.3 mL/min and a column temperature of 35 ℃. The mass spectrum data of Fu Fang Xiang Zuo Shui were collected by positive and negative ion modes to obtain the accurate mass number and secondary fragments.The compounds were qualitatively identified by reference material，Pubchem，Agilent Chinese medicine compound mass spectrum database and literature. Overall，112 compounds were identified，including 22 flavonoids，20 phenylpropanoids，18 organic acids，14 terpenoids，11 alkaloids，5 amino acids，and 22 other types of compounds. This study comprehensively elucidated the chemical basis of Fu Fang Xiang Zuo Shui，providing theoretical support for its quality control and pharmacodynamic substance research.关键词：ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry（UPLC-Q-TOF MS）;Fu Fang Xiang Zuo Shui;component analysis;flavonoids
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发布时间：2024-04-18 - 摘要：Dian green tea，a kind of green tea made from fresh leaves of large leaf tea variety in Yunnan province，present unique aroma quality. However，its characteristic aroma compounds were unclear. Headspace solid phase microextraction combing with gas chromatography-mass spectrometry/olfactometry（HS-SPME/GC-MS/O） was applied for the identification，quantitation，and sensory analysis of the aroma components of Dian green tea. 26 samples were divided into 4 groups according to their origins. Based on the traditional green tea sensory evaluation and quantitative descriptive analysis（QDA），three Dian green tea samples with high quality were selected. The results of HS-SPME/GC-MS/O showed that a total of 83 odorants were identified in S3，S6，S15 tea infusions，and the total relative content was 10.694%. Among which，aldehydes，ketones，and aromatic compounds were the main constituents. Twenty-two corresponding major aroma compounds were found. Among the 43 aroma substances with higher content（> 0.05%），alcohols，aldehydes，ketones，and esters commonly present pleasure odor notes，and play a direct role in the formation of aroma quality of Dian green tea. Alcohols mainly evoked an alluring flowery and fruity aroma. Aldehydes were closely related to the formation of tea aroma and various specific aroma characteristics，and their relative contents were high in Dian green tea. Aromatic aldehydes such as benzaldehyde mainly present almond-like note，while many kinds of aliphatic aldehyde were found and they mainly showed freshy and flowery odor. Most of the esters had a strong fruity flavor. However，methyl salicylate，a common odorant in tea，had the strong freshy perception. It contributed to the aroma quality of Dian green tea significantly. Ketones were another main aroma component in Dian green tea，and their aroma characteristics were closely related to their structures. It is worth mentioning that although low contents in Dian green tea，some aroma substances such as β-damasone and （E） -4-heptenal evokes obvious aroma in low concentrations because of their low odor thresholds in water. According to the results of the instrumental and sensory analysis，compounds present highest aroma intensities were 2，3-octanedione（milk-like），laurene（citrus-like/flowery），（E，E）-2，4-heptadienal（flowery），benzaldehyde（almond-like），linalool（citrus-like/flowery），hotrienol（lemon-like/sweety），geraniol（rose-like/citrus-like），limonene（citrus-like），geranylacetone（grassy），methyl sulfide（corn-like），3-methylbutanal（malty），6-methyl-5-hepten-2-one（popcorn-like/roasty），（4E，6Z）-alloocimene（basil-like），1-hexanol（grassy/almond-like），methyl salicylate（fresh，mint-like），β-damascenone（cooked apple-like），jasmonone（flowery），and β-ionone（flowery）. The above mentioned compounds were regarded as key odorants of Dian green tea. The study characterized the key aroma compounds of Dian green tea，which provides the theoretical basis for aroma quality and process improvement of Dian green tea.关键词：Dian green tea;characteristic aroma;headspace solid phase microextraction;gas chromatography-mass spectrometry/olfactometry（GC-MS/O）;volatile components
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发布时间：2024-04-18 - 摘要：In this study，nitrogen self-doped carbon quantum dots（N-CQDs） were prepared by microwave method using biomass tomato as carbon and nitrogen sources. The morphology，structure，stability，photoelectric properties，temperature sensitivity and cytotoxicity were studied by field emission transmission electron microscope（TEM），X-ray photoelectron spectrometer（XPS） and fluorescence luminescence photometer，and were applied to temperature sensing in living cells. The experimental results show that the prepared N-CQDs has strong stability，excellent photoelectric performance and strong sensitivity to temperature. In the temperature range of 25-65 ℃，the fluorescence intensity of N-CQDs decreases with the increase of temperature，and shows a good linear relationship. The N-CQDs can penetrate the cell membrane of 4T1 cells，showing low toxicity and biocompatibility，and good temperature sensing fluorescence properties in 4T1 cells. It is indicated that the N-CQDs has great potential and value in the field of fluorescence temperature sensing in living cells，and is of great significance in the development of non-destructive cell measurement of nanoferters. It is expected to become a temperature-sensitive fluorescence nanoprobe and be widely used in biomedical fields such as cell research.关键词：nitrogen self-doped carbon quantum dots;microwave method;photoelectric property;temperature sensitive property;cell temperature sensing
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发布时间：2024-04-18 - 摘要：A headspace gas chromatography-ion migration spectrometry（HS-GC-IMS） was used to identify the volatile components in different fresh rose breakable capsules samples. The sensory evaluation combined with principal component analysis（PCA），partial least squares discriminant analysis（PLS-DA），partial least squares regression（PLSR） and other multivariate statistical methods were used to identify the differences of major flavor components in different samples. The results showed as follows：①The sensory evaluation showed that the flavor characteristics of the breakable capsules samples were mainly floral，fruity and woody，supplemented by green，sweet and wine aromas. The floral and fruity characteristics of different samples showed significant differences（p<0.05）. ②The 22 main volatile flavor components in the samples were identified by GG-IMS，including 8 alcohols，3 esters，3 ketones，3 aldehydes，3 olefins，1 acids and 1 pyazines. The fingerprint directly showed that the aroma compounds with strong volatility，such as alcohols and esters，were significantly different among the samples. ③PCA and PLS-DA can effectively distinguish different samples and screen out 10 characteristic difference components（VIP>1）. PLSR showed that the sensory differences of samples were mainly related to ethyl 2-methylbutyrate，ethyl butyrate，cyclohexanone，acetophenone，octanal，n-propanol and linalool. The method can effectively distinguish different fresh rose breakable capsules samples，and its determination results are consistent with the results of sensory evaluation. It has the characteristics of accuracy，reliability，strong visualization，etc.，and can provide technical support for rapid inspection of sensory quality of cigarette breakable capsules products.关键词：tobacco;breakable capsules;GC-IMS;flavor;analysis
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发布时间：2024-04-18 - 摘要：A rapid method was developed for the determination of 29 odor-causing substances in water using headspace-arrow-solid-phase microextraction（HS-Arrow-SPME） coupled with gas chromatography-tandem mass spectrometry（GC-MS/MS）. By optimizing the pretreatment conditions and GC-MS/MS parameters，10 mL of water samples were selected to be added into a headspace vial，pre-incubated at 70 ℃ for 8 min with the assistance of 3.5 g NaCl salting-out，then extracted with a DVB/Carbon WR/PMDS Smart SPME Arrow extraction head for 20 min，and finally desorbed at the inlet of 240 ℃ for 3 min. The GC-MS/MS platform was configured with a VF-624 MS column（30 m×0.25 mm×1.4 μm） and detected in multiple reaction monitoring（MRM） mode. The results showed that the linearity of the 29 odor-causing substances in water was good in the ranges of 5-300 ng/L with correlation coefficients（r2） greater than 0.991. The limits of detection and the limits of quantitation ranged of 0.31-9.27 ng/L and 1.26-37.09 ng/L，respectively. The recoveries of 29 odor-causing substances spiked with the ultra-pure water as the blank matrix at spiked levels of 10，80，and 160 ng/L were in the ranges of 84.3%-112%，and the relative standard deviations（RSDs，n=6） were in the ranges of 0.10%-8.6%. The method has been used for the determination of 29 targets in real water samples and can meet the requirements for the detection of trace odor-causing substances.关键词：HS-Arrow-SPME;GC-MS/MS;water;odor-causing substance
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发布时间：2024-04-18 - 摘要：An improved QuEChERS/ultra performance liquid chromatography-tandem mass spectrometry（QuEChERS/UPLC-MS/MS） analytical method was developed for the determination of 88 pesticide residues in Tibetan tea. Tibetan tea samples were extracted with 1% acetic acid acetonitrile and salted with 2 g NaCl，cleaned up by polyvinylpyrrolidone（PVPP），octadecyl bonded silica gel（C18） and graphitized carbon black（GCB），and then separated with 0.01% formic acid aqueous solution（containing 2 mmol/L ammonium formate） and 0.01% formic acid methanol as the mobile phases. The analytes were separated on an ACQUITY UPLC BEH C18（50 mm×2.1 mm，1.7 μm） column to achieve the separation within 15 min，detected in electrospray positive ionization mode with multiple reaction monitoring（MRM） mode and quantified by matrix matching curve external standard method. The results showed that 88 pesticides in Tibetan tea showed good linear correlations with correlation coefficients（r） not less than 0.999 0 in the corresponding concentration ranges，and the limits of detection（LODs） and limits of quantitation（LOQs） were in the ranges of 0.15-3 μg/kg and 0.5-10 μg/kg，respectively. Average recoveries of the 88 pesticides in Tibetan tea at three spiked levels（1，2，and 10-fold LOQ） were 73.2%-108%，73.2%-109%，72.5%-110%，and the relative standard deviations（RSDs） were not more than 12%. The method was applied to 12 batches of actual samples and pesticides were detected in all samples，among which 4 batches of imidacloprid exceeded the limit value. The method is sensitive，simple and rapid，and could meet the rapid detection requirements of 88 pesticides in Tibetan tea.关键词：improved QuEChERS;Tibetan tea;ultra performance liquid chromatography-mass spectrometry;pesticide residues
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发布时间：2024-04-18 - 摘要：Carbon quantum dots（CDs） prepared from orange peel were employed to construct a dual-emission ratiometric fluorescent probe（Eu3+-CDs） with europium ions（Eu3+） for the detection of the antibiotic tetracycline hydrochloride. The Eu3+-CDs fluorescent probe exhibits two distinct fluorescence peaks at 370 nm excitation：a robust blue peak at 425 nm and a comparatively moderate red peak at 617 nm. With the concentration of tetracycline hydrochloride increased，Eu3+ chelated with tetracycline hydrochloride to form more complexes. As a result，the fluorescence of CDs at 425 nm（IF425） steadily dropped while that of europium complexes at 617 nm（IF617） increased. This variation in fluorescence intensity ratio of IF617/IF425 allowed for the measurement of the tetracycline hydrochloride content. The effects of Eu3+ concentration，pH value and reaction time on the fluorescence intensity were investigated.Under the optimal conditions，the dual-emission ratiometric fluorescent probe had a specific recognition ability for tetracycline hydrochloride. A good linear relationship between the fluorescence intensity ratio（IF617/IF425） and the concentration of tetracycline hydrochloride（10-100 μmol/L） was obtained. The linear equation was IF617/IF425= 0.015 61c（μmol/L） + 0.050 81，and the linear correlation coefficient was r2 = 0.992 6 with the detection limit of 5.09 μmol/L. The method was successfully utilized to detect the content of tetracycline hydrochloride in pork with the spiked recoveries of 102% to 110% and the relative standard deviations of 0.20%-2.4%.关键词：dual-emission ratiometric fluorescence probe;carbon quantum dots（CDs）;europium ion（Eu3+）;tetracycline hydrochloride
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发布时间：2024-04-18 - 摘要：This study innovatively developed a rapid classification method for coal and gangue，integrating near infrared spectroscopy technology with a one-dimensional residual network（1D-ResNet）. To ensure the diversity of experimental samples，430 samples of coal and gangue were collected from multiple coal mines in provinces such as Henan，Hebei，and Shandong. Abnormal samples were eliminated based on Euclidean distance to obtain a high-quality dataset for modeling. Building on this，a 1D-ResNet-based classification model was constructed to accurately capture the complex mapping relationships between coal，gangue，and their spectral characteristics. This approach effectively solved the problem of gradient vanishing and deeply mined the spectral features of coal and gangue，resulting in highly accurate analysis. After five-fold cross-validation，the model achieved an average accuracy of 96.26%，significantly outperforming traditional machine learning algorithms such as support vector machines and random forests. The model demonstrated high consistency in the trend of loss function changes across both the training and test datasets，indicating good generalization ability. Tests revealed that the model processes every hundred samples in just 16.230 milliseconds，further highlighting its advantages and potential application value in the online sorting field for coal and gangue.关键词：coal gangue identification;near infrared spectroscopy;deep learning;residual network
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发布时间：2024-04-18 - 摘要：A fluorescent probe with a certain rigid skeleton was prepared by amidation of oligaramide trimer diacid with intra-molecular three center hydrogen bond and 3-aminocoumarin. The structure of the probe was characterized by nuclear magnetic resonance（NMR） and mass spectrum（MS）. The selective recognition，anti-interference and reversible properties of the probe were studied by fluorescence emission spectra. The coordination ratio and detection limit of the probe and Hg2+ were determined，and the ability of the probe to quantitatively detect Hg2+ in different water samples was also studied. The results showed that the probe molecule showed excellent selectivity to Hg2+ in mixed solution，and was not interfered by other metal ions（K+，Na+，Ca2+，Mg2+，Cu2+，Zn2+，Pb2+，Cd2+，Fe3+，Mn2+，Ni2+，Ag+，Cr3+，Al3+，Co2+）. The probe has good reversibility for Hg2+. Their coordination ratio is 1∶1，and the detection limit is 2.08×10-7 mol/L，which met the requirements of actual water sample detection，and the detetion results are similar to those of atomic fluorescence method. The luminescence mechanism of Hg2+ recognition by the probe molecule was also deduced by the means of infrared spectrum（IR） and hydrogen nuclear magentic resonance（1H NMR）. The probe can be used for the quantitative detection of Hg2+ in different water samples with high accuracy and precision.关键词：coumarin;oligaramide;mercury ion;fluorescent probe;water sample
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发布时间：2024-04-18 - 摘要：A rapid method for the determination of four aflatoxins in various Chinese medicinal materials（CMMs） was established by fully automated immunomagnetic bead purification technology. Aflatoxins in CMMs were efficiently extracted by acetonitrile-water（9∶1），followed by enrichment and purification program of immuno-magnetic beads，with elution accomplished by methanol containing 0.5% acetic acid. Separation was achieved on an Inertsil ODS-3 C18 column （250 mm × 4.6 mm，5 μm） with a mobile phase consisting of acetonitrile，methanol，and water. Isocratic elution was operated with a flow rate of 1.0 mL·min-1 and analyzed by high performance liquid chromatography-fluorescence detector（HPLC-FLD）. The method was validated and applied to five CMMs matrices known to be susceptible to aflatoxin contamination. The method had a good linear relationship with correlation coefficients（r2） all reach 0.999 9. The limits of detection were 0.06-0.2 μg·kg-1 and the limits of quantitation were 0.12-0.40 μg·kg-1. The average recoveries in different matrices were 71.9%-116%，with the relative standard deviations ranging of 0.10%-6.9%. The automated method takes less than 18 min to finish the batch purification of 24 samples. It appeared an outstanding efficiency that increased by nearly 85% compared with the immunoaffinity column method in the Chinese Pharmacopoeia. This established method was rapid，accurate，and highly versatile，which is suitable for the batch determination of four aflatoxins in various CMMs.关键词：automated immunomagnetic beads;rapid determination;Chinese medicinal materials（CMM）;aflatoxins;high performance liquid chromatography（HPLC）
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发布时间：2024-04-18
Scientific Papers
- 摘要：In order to accurately measure the composition and content of volatile organic compounds（VOCs） in aerosol products，a specific device was designed in this paper to separate the aerosol propellant from the non-propellant.The propellant from the aerosol was collected using collection bags，and the non-propellant part of the VOC was extracted using liquid-liquid extraction method.The samples were analyzed by using the established analytical method of gas chromatography-mass spectrometry/flame ionization detector（GC-MS/FID）. The propellant gas fraction content was determined by the normalization method. The non-propellant VOCs were selected based on the detected VOCs species，and eight VOCs substances were selected to establish standard curves.Good linearity was obtained in the mass concentration ranges，with the correlation coefficients（r2） all greater than 0.99. The detection limits and the quantitation limits of the analytes were in the ranges of 0.25-0.50 mg/L and 0.50-1.00 mg/L，respectively. The recoveries of each analyte were obtained in the ranges of 90.5%-105%，with relative standard deviations（RSDs） ranging from 1.8% to 9.3%. The established method was applied to analyze six aerosol products with different functions and calculate their ozone formation potentials. The results showed that propane，butane and dimethyl ether were mainly detected in the propellant fraction，and benzene，alkanes，cycloalkanes，monoterpenes，carboxylic acid derivatives，and ethers were detected in the non-propellant fraction，with benzene and monoterpenes being higher. Therefore，the analytical method constructed in this paper can provide certain reference for enterprises to improve their product formulations，and also provide technical support for regulatory authorities.关键词：liquid-liquid extraction;gas chromatography-mass spectrometry/flame ionization detector coupling;aerosol;VOCs
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发布时间：2024-04-18 - 摘要：The content of ephedrine alkaloids and morphine is of great significance for the quality evaluation of Keke tablets. In view of the time and effort of traditional methods for the quality analysis of Keke tablets，this study was based on near infrared spectroscopy（NIRS） to establish a rapid，non-destructive and efficient method for the quality evaluation of Keke tablets. The quantitative analysis model of ephedrine alkaloids and morphine was established by NIRS and partial least squares regression（PLSR），and the performance of the model was optimized by different pretreatment methods and variable selection methods. R-square of calibration set（Rc2），R-square of prediction set（Rp2） and residual predictive deviation（RPD） were calculated as the evaluation index of the correction model. The results showed that the pretreatment method is standard normal variable transformation（SNV） combined with variable selection for competitive adaptive reweighted sampling（CARS） model has the better performance. The Rc2，Rp2 and RPD of the NIR models of ephedrine alkaloids and morphine in Keke tablets were 0.91，0.93，4.00 and 0.92，0.94 and 4.24，respectively，indicating that the model performance was good and the quality detection of Keke tablets was realized. The results show that NIRS and CARS can be used for rapid and non-destructive analysis of Keke tablets，which can provide a good reference for quality detection of Keke tablets.关键词：Keke tablet;near infrared spectroscopy;ephedrine alkaloids;morphine
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发布时间：2024-04-18 - 摘要：Residual dimethylcyclosiloxanes（DMCs） in intelligent electronic products may enter the environment with discarded products. A method was developed for the determination of seven DMCs（D3，D4，D5，D6，D7，D8，D9） in terminal electronic device materials，including silicone rubber，adhesive and plastic given their complex matrices，low solubility and poor dispersion. Samples with particle size of 0.5 cm×0.5 cm were ultrasonic extracted by acetone. The DMCs were determined by gas chromatography-mass spectrometry（GC-MS） in mode of selected characteristic fragment ions. The GC separation was achieved on an SH-Rxi-5Sil MS capillary column（30 m×0.25 mm×0.25 µm）. Seven DMCs showed good linear relationships （r2≥0.999 3） in the concentration range of 0.1-10.0 mg/L. Average recoveries were 83.8% to 105%，with relative standard deviations（RSDs，n=6） of 1.5%-4.6% in three typical terminal electronic device materials. The method quantitation limit was 0.5 μg/g. The method was applied to determine the DMCs in 7 different samples of terminal electronic device materials. DMCs were detected in 6 samples，with total DMCs contents of 30.0-1.6 × 103 μg/g.关键词：dimethylcyclosiloxanes;gas chromatography-mass spectrometry;intelligent electronic products;silicone rubber;adhesive;plastic
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发布时间：2024-04-18 - 摘要：A method for the analysis of distearyl dimethyl ammonium chloride（DSDMAC） in various types of cosmetics was established based on high performance liquid chromatography-evaporative light scattering detector（HPLC-ELSD）. Cosmetics were dispersed with acetonitrile aqueous solution（volume ratio 2∶1） and extracted by sodium chloride with oscillation under the oscillation frequency of 160 r/min for 30 minutes. After extraction，the samples were eluted by gradient elution using acetonitrile and 100 mmol/L ammonium acetate aqueous solution（pH 5.5） as the mobile phases，with an AcclaimTM Surfactant column（150 mm×4.6 mm，5 μm）. DSDMAC analysis could be completed within 18 min. The external standard method was applied for quantitative determination. The method showed a good linear relationship for DSDMAC in the concentration range of 10-200 mg/L，with the correlation coefficient（r2） as 0.999 4. The limits of detection（LOD） and quantitation（LOQ） were 3.27 mg/kg and 9.96 mg/kg，respectively. The average recoveries in makeup remover oil，hair care essential oil，eye-shadow，pancake，toothpaste，lipstick，emulsion，shampoo，essence water and mouthwash were from 82.5% to 101%，with the relative standard deviations（RSDs，n=6） not exceeded 6.3%. This method was applied to 133 commercial samples，and the content of DSDMAC in one positive emulsion exceeded the regulatory requirement. With good precision and accuracy，the developed method was suitable for the quantitative analysis of DSDMAC in typical kinds of cosmetics，which could provide technical support for the quality and safety monitoring of cosmetics.关键词：cosmetics;distearyl dimethyl ammonium chloride;high performance liquid chromatography;evaporative light scattering
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发布时间：2024-04-18
Experimental Techniques and Methods
- 摘要：Metal organic framework materials（MOFs） are a highly promising material for adsorbing pollutants in water. Among them，the Lavoisier Institute material（MIL） stands out among many MOFs due to its great stability and numerous adjustable sites. Compared with other MILs，MIL-101 has the characteristics of larger specific surface areas，more active sites and high stability in water. In this work，the research progress of MIL-101 in the fields of adsorption and removal of organic pollutants from water in recent years were reviewed in the structure introduction，modification，t-application and removal mechanism. Finally，an analysis and outlook were conducted on the application prospects of MIL-101 adsorbent materials.关键词：MIL-101;adsorption;modification;organic contaminants;water
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发布时间：2024-04-18
Review
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