最新刊期
卷 44 ， 期 3 ， 2025
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摘要：Enzymatic biofuel cells（EBFC）-based self-powered sensing device has the advantages of simple structure，easy miniaturization，and no need for external power supply. It exhibits potential application prospects in clinical diagnosis，environmental monitoring，biosensing and other fields. Reduced graphene oxide/Aurum nanoparticles/multi walled carbon nanotubes（rGO/AuNPs/MWCNTs） nanocomposite was used as electrode substrate materials. The bioanode and cathode of enzymatic biofuel cells were prepared via immobilization of glucose oxidase（GOx） and electroposition growth of manganese dioxide（MnO2） on the surface of rGO/AuNPs/MWCNTs modified electrodes，respectively. An enzymatic biofuel cells-based self-powered glucose biosensor（EBFC-SPGB） was constructed by combining as-prepared bioanode and cathode in supporting electrolyte at room temperature. In the presence of target glucose，the GOx fixed on the surface of the bioanode promotes an enzymatic reaction. The electrons generated by catalyzing glucose transferred to the cathode through an external circuit，resulting in a reduction reaction of MnO2 on the cathode surface and generating an electrochemical response signal. Due to the excellent conductivity，biocompatibility and large specific surface area of rGO/AuNPs/MWCNTs nanocomposite，the synergistic effect of nanocomposite can significantly increase loading amount of GOx and effectively promote electron transfer on the electrode surface. The maximum power output signal of the constructed EBFC-SPGB shows a good linear relationship with glucose concentration in the range of 1-30 mmol/L，with a detection limit（S/N=3） of 0.3 mmol/L，which can be applied to analysis of glucose concentration in human serum samples.关键词：glucose;nanocomposite;enzymatic biofuel cells;self-powered glucose biosensor68|18|0更新时间：2025-03-17 -
摘要：In this paper，a detection and evaluation method of lithium-ion battery state of health（SOH） is proposed by integrating the improved whale optimization algorithm and support vector regression（IWOA-SVR）. Firstly，the charging/discharging data under different charging/discharging strategies are collected，and the critical battery aging characteristic parameters are extracted. Then Pearson correlation analysis is applied to verify the strong correlation between the parameters and the SOH，and the algorithm integrates the adaptive weight adjustment mechanism and Levy flight strategy into the traditional whale optimization algorithm，which effectively overcomes the problem of the large error of the traditional method when evaluating the SOH online. Finally，in order to verify the effectiveness of the algorithm，experimental test data under two typical operating conditions of constant-current and constant-voltage charging and constant-current charging are used for validation，and the results show that the IWOA-SVR detection method has higher stability and accuracy，and the maximal error can be controlled within 1.4%. Meanwhile，IWOA-SVR significantly outperforms the comparison algorithms in two key evaluation metrics，namely，mean absolute percentage error（MAPE） and root mean square error（RMSE），which fully proves its high accuracy and strong robustness in the online detection of SOH in lithium-ion batteries.关键词：lithium-ion batteries;improved whale optimization algorithm;support vector regression;state of health detection33|21|0更新时间：2025-03-17 -
摘要：This article presented a facile fabrication process for polydimethylsiloxane（PDMS） composite gold nanotrisoctahedra（Au NTOH） for a flexible SERS sensor with high sensitivity. Specifically，Au NTOH with excellent SERS behaviors was synthesized using a seed-mediated growth method and the dimensions of the Au NTOH was easily tuned. In addition，the influence of size on the SERS performance of their monolayers was systematically investigated，and the Au NTOH with the size of 61 nm possessed the best SERS performance. Importantly，a hydrophilic-substrate-assisted interfacial self-assembled monolayer transfer technique was proposed to transfer Au NTOH onto PDMS films，resulting in forming flexible and transparent Au NTOH@PDMS substrates. Furthermore，the excellent signal homogeneity of this substrate was demonstrated and the sensitivity was verified by a measurement of crystal violet（CV） as low as 1×10-8 mol/L. As a result，this SERS sensor is progressing for applying in the identification of trace contaminants in broad fields.关键词：Au NTOH;PDMS;interfacial self-assembly;SERS;crystal violetCLC Number：O656.21;O657.37 Document code：A Article IC：1004-4957（2025）03-0411-0943|13|0更新时间：2025-03-17 -
摘要：To enhance the accuracy of inferring drowning fluid temperature using blood biochemical indicators，this study conducted biochemical tests on fresh cardiac blood samples from SD rats subjected to drowning. Statistical tests and machine learning were employed to develop regression models linking drowning fluid temperature to blood biochemical markers. A total of 250 male rats were randomly divided into four experimental groups（based on water temperature during drowning）：cold water drowning（8-10 ℃），normal temperature drowning（20-22 ℃），warm water drowning（30 ℃），and hot water drowning（45 ℃），along with a control group（cervical dislocation，n=50 per group）. Rats in the experimental groups were individually immersed in pre-adjusted water tanks until drowning occurred. Immediately after death，the chest cavity of each rat was opened，and approximately 2 mL of right heart blood was rapidly collected. Blood samples were left to stand at room temperature for 1.5 hours before serum supernatant was separated by centrifugation（2 500 r/min for 10 minutes at 4 ℃） and transferred to labeled EP tubes. From each tube，200 μL of serum was extracted into a dedicated serum cup for biochemical analysis.Using the Chinese Inova DS-401 automated biochemical analyzer，14 biochemical markers were tested in the samples：alanine aminotransferase（ALT），aspartate aminotransferase（AST），alkaline phosphatase（ALP），gamma-glutamyl transferase（GGT），creatinine（Cr），uric acid（UA），urea，glucose（GLU），high-density lipoprotein cholesterol（HDL_C），low-density lipoprotein cholesterol（LDL_C），cholesterol（CHO），triglycerides（TG），calcium ion（Ca2+），and magnesium ion（Mg2+）. Normality，homogeneity of variance，ANOVA，post-hoc tests，and correlation analyses were performed on the 14 biochemical indicators. KNN regression models were then utilized to screen critical features，benchmark tests were conducted，regression models were established，and finally，model tuning，evaluation，and interpretation were performed.Results showed that all 14 biochemical indicators conformed to normal distribution across different temperature groups，with significant differences in mean values within groups（p<0.05），albeit 18.6% of pairwise comparisons exhibited non-significant differences. Low collinearity（<70%） was observed among indicators. The regression model selected ALP，GGT，Cr，urea，UA，HDL_C，CHO，TG，Ca2+，and Mg2+ as the 10 most important biochemical markers. The KNN regression model built with these variables，after hyperparameter optimization，achieved RMSE=1.872 and R2=0.979 2 on the test set，with Mg2+，TG，and ALP having the greatest negative impact on the model. Compared to traditional regression models，the model established in this study fully leverages sample data，offering simplicity in data preprocessing，high accuracy，and good interpretability，making it suitable for inferring drowning fluid temperature.关键词：drowning fluid temperature;blood biochemistry;drowning;machine learning39|27|0更新时间：2025-03-17 -
摘要：Three novel Schiff bases，namely 1，4-butane diimino-4-bromo-2-methoxyphenol（Br-4C），1，5-pentanediimino-4-bromo-2-methoxyphenol（Br-5C），1，6-hexanediimine-4-bromo-2-methoxyphenol（Br-6C），were prepared by the condensation reaction of 5-bromo-2-hydroxy-3-methoxybenzaldehyde with different diamines（butylenediamine，pentenediamine and hexanediamine） at the molar ratio of 2∶1，respectively. The structure of three Schiff bases was characterized by infrared spectroscopy（IR），nuclear magnetic hydrogen spectroscopy（1H NMR） and nuclear magnetic carbon spectroscopy（13C NMR），and single crystal X-ray diffraction and Hirshfeld surface analysis were performed for Br-4C. In addition，the solid-state luminescence behavior of the above compounds was also studied，Br-4C，Br-5C and Br-6C all exhibit wide emission spectra（500-700 nm） at the excitation wavelengths of 365，396 and 396 nm. At the same time，the fluorescence intensity of the three Schiff bases in common solvents were recorded，and it is found that the strongest and weakest luminescence intensity is appeared in N，N´-dimethylformamide（DMF） and water solution，respectively. Therefore，the identification characteristics of metal ions by Br-4C，Br-5C and Br-6C in DMF solution were studied by fluorescence spectrometry. The results show that the three probes have high selectivity to Fe3+. In addition，Fe3+ was detected with test paper strips of Br-4C，Br-5C and Br-6C probes under natural light. The three probes can also be used to detect Fe3+ in actual water samples.关键词：5-bromo-2-hydroxy-3-methoxybenzaldehyde;condensation reaction;Schiff base;fluorescent probe;Fe3+41|23|0更新时间：2025-03-17 -
摘要：A rapid and accurate method for the simultaneously determination of 3 gastric motility drugs（domperidone，mosapride and cisapride） in milk powder was developed in this study using filter-through solid phase extraction（FSPE）/ultra high performance liquid chromatography-quadrupole-linear ion trap mass spectrometry（UPLC-MS/MS-QTRAP）. Samples were dissolved in warm water at 45 ℃，extracted using 10 mL acetonitrile，centrifuged and purified by Oasis PRiME HLB solid phase extraction column for reducing impurity interference in samples. The separation of 3 target compounds was performed on an Agilent Poroshell 120 EC-C18 column（100 mm×3.0 mm，2.7 µm） using gradient elution of methanol and 20 mmol/L ammonium acetate aqueous solution as mobile phases. Analytes were detected in positive electrospray ionization（ESI+） with multiple reaction monitoring（MRM） mode scanning，and quantitatively analyzed using the internal standard method. The 3 kinds of gastric motility drugs showed good linear relationship in the range of 0.05-5.0 μg/L with correlation coefficients（r2） not less than 0.999 4. The detection limits reached 0.07 μg/kg，and the quantitation limits reached 0.2 μg/kg. The average recoveries of actual blank spiked sample ranged from 93.2% to 105%，and the relative standard deviations（RSDs） ranged from 1.3% to 10%. This method has higher analysis efficiency，higher sensitivity and accuracy，and is suitable for rapid detection of 3 gastric motility drugs in milk powder.关键词：filter-through solid phase extraction（FSPE）;ultra high performance liquid chromatography-quadrupole-linear ion trap mass spectrometry（UPLC-MS/MS-QTRAP）;milk powder;gastric motility drugs29|25|0更新时间：2025-03-17 -
摘要：Cerium and copper doped nanozyme（F68-Ce-Cu） with peroxidase-like activity was prepared for the colorimetric analysis of nicotine in “tea tobacco” and “flower tobacco”. In the presence of H2O2，F68-Ce-Cu could catalyze the conversion of colorless 3，3'，5，5'-tetramethylbenzidine（TMB） into blue oxidized TMB（oxTMB）. It had been found that nicotine has a significant sensitizing effect on the peroxidase-like activity of F68-Ce-Cu without interference from other possible components in cigarette-like products. The results of the Michaelis-Menten kinetics study showed that compared to the Ce（Km=2.04 mmol/L） or Cu（Km=9.46 mmol/L） based-nanozyme alone，the Km of F68-Ce-Cu was significantly reduced（Km=1.51 mmol/L），and the Km of “F68-Ce-Cu+nicotine” system was 0.25 mmol/L，which was 6 times more strongly bound to the substrate after the addition of natural nicotine. The results of Zeta potential determination showed that there was a strong adsorption between F68-Ce-Cu and nicotine，and it could promote the production of more ·OH and O2·-，which significantly increased the peroxidase-like activity. In the range of 0.017-0.52 mg/mL，nicotine concentration showed a good linear relationship with absorbance at 654 nm，and the detection limit reached 0.008 mg/mL. In the actual cigarette-like products，the recovery of the method was in the range of 90.9%-103%，and the relative standard deviation was in the range of 2.1%-4.6%，which was almost consistent with the detection results of high performance liquid chromatography，indicating that the method was stable and accurate.关键词：nicotine;cigarette-like products;nanozyme;peroxidase-like activity;colorimetric detection39|36|0更新时间：2025-03-17 -
摘要：Hyperspectral imaging technology was used to analyze the coating color uniformity and the depth of coating color of coated cabbage seeds of 4 different varieties and coated cabbage seeds treated with coating agents at 3 different concentrations during the coating process. The average spectral reflectance of 240 seed samples was extracted. The original spectra were preprocessed and optimized through 4 preprocessing methods. Then，4 methods including the competitive adaptive reweighted sampling algorithm（CARS），successive projections algorithm（SPA），uninformative variable elimination transformation method（UVE），and genetic algorithm partial least squares algorithm（GAPLS） were used to extract the characteristic wavelengths. Partial least squares regression（PLSR），multiple linear regression（MLR） and principal component regression（PCR） were established based on the optimized characteristic wavelengths. The results showed that the coating effect on kale seeds was the most obvious，followed by that on Jiaxiang taste-type cabbage，and the coating effects on Zhonggan 15 and purple cabbage were close. The Baseline method was preferably used to preprocess the chromaticity value L*，the Normalize method was used to preprocess the chromaticity value a，and the SNV method was used to preprocess the chromaticity value b. The characteristic wavelengths extracted by the GAPLS method were used to establish the quantitative prediction models for L* and b，the characteristic wavelengths extracted by the UVE method were used to establish the quantitative prediction model for the chromaticity value a. The L* model established by PLSR had the best effect（Rc=0.814，Rp=0.640；RMSEC=1.150，RMSEP=1.852），the model for the chromaticity value a established by MLR had a better effect（Rc=0.981，Rp=0.964；RMSEC=2.563，RMSEP=3.243），and the model for the chromaticity value b established by PCR had the best effect（Rc=0.917，Rp=0.913；RMSEC=2.552，RMSEP=2.589）. The research can provide technical support for the online monitoring of seed chromaticity.关键词：hyperspectral imaging;coated cabbage seeds;color;detection28|18|0更新时间：2025-03-17 -
摘要：A dispersive liquid-liquid microextraction（DLLME） device based on hydrophobic porous polydimethylsiloxane sponge（PDMS-Sponge） was established to achieve rapid and efficient extraction of 12 common benzodiazepines drugs in urine. Direct injection test and identification method were achieved with the assistance of gas chromatography-mass spectrometry（GC-MS）. The preparation of hydrophobic porous organic PDMS sponge material was achieved through the framework provided by sugar cubes. Fourier transforminfrared spectrometer and scanning electron microscopy were used to characterize the microstructure and performance of PDMS-Sponge. The extraction device was completed by combining medical syringes，magnetic stirrers，and rubber plugs. Quantitative analysis using the internal standard method was conducted to investigate the effects of dispersant，pH value，magnetic stirring time，and dispersant dosage on the extraction efficiency of 12 drugs in urine. The results showed that PDMS-Sponge is a hydrophobic porous material，which can be combined with a medical syringe to construct a new dispersive liquid-liquid microextraction device. Using 100 µL of dichloromethane as the extractant，50 µL of acetonitrile as the dispersant，a speed of 800 r/min，and magnetic stirring for 1 min can achieve the extraction and enrichment of the analytes. Under optimal conditions，12 common hypnotics in urine have a good linear relationship in the range of 0.1-10 µg/mL，with correlation coefficients（r2） greater than 0.99，detection limits of 0.025-0.200 µg/mL，and quantitation limits of 0.050-0.400 µg/mL. The recoveries at three spiked levels was 64.4%-112%，and the relative standard deviations was 0.80%-9.4%. The newly dispersive liquid-liquid microextraction device can complete the efficient extraction and concentration of hypnotics in urine in a few minutes，and rapid testing can be achieved with the assistance of GC-MS，providing a green，efficient，simple and inexpensive new dispersive liquid-liquid microextraction solution.关键词：polydimethylsiloxane sponge;dispersive liquid-liquid microextraction;benzodiazepines;urine;gas chromatography-mass spectrometry40|24|0更新时间：2025-03-17 -
摘要：The differences between near infrared（NIR） spectrometers make it challenging to share prediction models across different instruments，limiting the widespread application of this technology. To reduce the difficulty of rebuilding prediction models after spectral shift，this paper proposes a near infrared spectral model transfer method based on a convolutional bridged twin denoising autoencoder（CBSDAE）. This method utilizes the encoder of the convolutional denoising autoencoder（CDAE） to extract the hidden features of the spectra and fits a transfer mapping function between the hidden spectral features of the target and source instruments using a convolutional neural network（CNN）. Finally，the transferred spectra are reconstructed through the decoder of the CDAE. To validate its effectiveness，evaluations were conducted from two perspectives：NIR spectra of tobacco leaves and chemical component prediction results. The findings show that the spectra from the target instrument closely overlap with those from the source instrument after transfer using the CBSDAE method. Compared with direct standardization（DS），piecewise direct standardization（PDS），spectral subtraction correction（SSC），Shenk’s algorithm，CNN and deep autoencoder，the average relative error in nicotine prediction decreased by 6.42%，5.84%，5.32%，5.24%，4.35% and 4.85%，respectively，after applying the CBSDAE method for spectral transfer. Additionally，the root mean square error of prediction（RMSEP） and correlation coefficient were superior to those of the aforementioned methods. These results indicate that the proposed method is an effective approach for model transfer.关键词：model transfer;encoder;twin;convolutional bridge;near infrared spectroscopy66|42|0更新时间：2025-03-17 -
摘要：An analytical method was proposed for the enantiomeric separation and residual determination of the enantiomers of oxazepam and temazepam in aquaculture products by liquid chromatography-tandem mass spectrometry（LC-MS/MS）. Samples were extracted twice with acetonitrile and the centrifuged extractions were blew to dryness under nitrogen gas at 40 ℃. Then，the dried residues were dissolved with 2 mL 50% acetonitrile-water solution，followed by dispersive solid phase extraction（dSPE） cleanup protocol prior to be injected into LC-MS/MS. The chromatographic separation of the targeted enantiomers of oxazepam and temazepam were conducted on an EnantioPAK® Y1-R column（5 μm，150 mm×4.6 mm） under isocratic elution procedure，utilizing acetonitrile and 0.1% formic acid-5 mmol/L ammonium acetate solution as mobile phases. The targeted enantiomers were determined with internal standard method，operating in positive electrospray ionization scanning mode（ESI+） and multiple reaction monitoring（MRM） mode. Excellent linearity for four targeted enantiomers were prepared in the concentration ranges of 0.5-50 μg/L，with correlation coefficients（r2） not less than 0.999 0. The limits of detection（LODs） and the limits of quantitation（LOQs） in aquaculture product samples were 0.2 μg/kg and 0.5 μg/kg，respectively. The average recoveries of targeted enantiomers fortified in five negative sample matrixes at three spiked concentration levels ranged from 82.6% to 107%，with relative standard deviations（RSDs，n=6） not more than 9.2%. The newly developed method is sensitive and reliable，and is suitable for the residue analysis of the enantiomers of oxazepam and temazepam in various aquaculture product matrixes.关键词：liquid chromatography-tandem mass spectrometry（LC-MS/MS）;enantiomers;enantiomeric separation;dispersive solid phase extraction（dSPE）;aquaculture product39|27|0更新时间：2025-03-17 -
摘要：A method for the determination of N-methyl-2-pyrrolidone（NMP） residues in lubricating oil using gas chromatography-mass spectrometry（GC-MS） has been established. Lubricating oil samples were dissolved in tert-butyl methyl ether，and then precipitated by adding acetonitrile. The target substance NMP was retained in the supernatant and determined by gas chromatography-mass spectrometry with external standard method for quantification. Results showed that NMP had a good linear relationship in the range of 0.5 mg/L to 50.0 mg/L，the detection limit was 8.0 mg/kg，and the quantitation limit was 20.0 mg/kg. At three spiked levels of 20 mg/kg，100 mg/kg and 200 mg/kg，the recoveries of NMP in different types of lubricating oils were between 96.2% and 108%，with relative standard deviations（RSDs） ranging from 0.99% to 4.5%. The method is quick，easy，accurate and sensitive，which is suitable for determination of NMP in lubricating oil.关键词：N-methyl-2-pyrrolidone;lubricating oil;gas chromatography-mass spectrometry;dissolution-precipitation method32|29|0更新时间：2025-03-17
Scientific Papers
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摘要：In this study，a novel method for the simultaneous detection and quantification of oxyphenisatin，its nine ester derivatives（oxyphenisatine diacetate，oxyphenisatine dipropionate，dicyclopropafenedine，oxyphenisatine dibutyrate，oxyphenisatine divalerate，oxyphenisatine dihexylester，dicyclohexylphenol butyl，oxyphenisatine dienanthate and oxyphenisatine dioctanoate），and five analogues（bisoxatin，4-chloro-oxyphenisatine，bisoxatin acetate，4-chloro-oxyphenisatine diacetate and triacetyldiphenolisatin） in ferment plum using ultra performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS）. The sample was ultrasonically extracted with methanol，volume fixed and centrifuged. The separation was performed by Waters Acquity BEH C18 column（50 mm×2.1 mm，1.7 μm） by gradient elution with 5 mmol/L ammonium acetate aqueous solution and acetonitrile as mobile phases. The compounds were step scanned using an electrospray ionization source in the positive and multiple reaction monitoring（MRM） modes，and analyzed by matrix matched external standard method.The results showed that 15 compounds achieved great linearity in the linear ranges，with a correlation coefficients（r2） not less than 0.998 1. The limits of detection（LODs） of 15 compounds ranged from 0.005 to 0.025 mg/kg，and the limits of quantification（LOQs） ranged from 0.015 to 0.075 mg/kg. The average recoveries ranged from 72.8% to 114%，while the relative standard deviations（RSDs） were between 1.1% to 9.0%. The method was successfully applied to the determination of 10 fermenter plum samples obtained from different Taobao shops. A total of 9 illegal adulterants were detected，namely oxyphenisatin，oxyphenisatinedipropionate，oxyphenisatine dibutyrate，oxyphenisatinedivalerate，oxyphenisatine dihexylester，dicyclohexylphenol butyl，bisoxatin，4-chloro-oxyphenisatine，4-chloro-oxyphenisatine diacetate. The contents ranged from 0.1 to 851.9 mg/kg. The method is accurate，sensitive，rapid，and it is suitable for detection of the 15 illegal adulterants in ferment plum.关键词：oxyphenisatin;ester derivatives;analogues;ultra performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS）;ferment plum30|24|0更新时间：2025-03-17 -
摘要：A new high performance liquid chromatography-tandem mass spectrometry method for screening and confirmation of the oxyphenisatin，phenolphthalein and their derivants in enzyme food was developed. The sample was extracted with acetonitrile-water，followed by centrifugation. The supernatant was then filtered through a membrane filter. The separation was performed on Hypersil Gold C18 column with gradient elution with 0.1% formic acid aqueous solution and 0.1% formic acid acetonitrile as mobile phases. The target compounds were determined by positive electrospray ionization under the multiple reaction monitoring（MRM） mode，which quantitative analysis by external standard method with matrix curve. Nine analytes showed good linear relationships in the range of 5-100 μg/L with correlation coefficients not less than 0.999 0. The results showed that the limit of quantification was 0.05 mg/kg. The average spiked recoveries showed a variation from 80.4%-101% for the three fortification levels，with relative standard deviations between 1.2% and 7.8%. This procedure was noticeably simple，rapid，sensitive and accurate. Therefore，this method is suitable for batch determination of the nine oxyphenisatin，phenolphthalein and their derivants in enzyme food.关键词：oxyphenisatin;phenolphthalein;derivant;high performance liquid chromatography-tandem mass spectrometry;enzyme food31|8|0更新时间：2025-03-17 -
摘要：A new method for the simultaneous determination of 11 mycotoxins（aflatoxin B1，aflatoxin B2，aflatoxin G1，aflatoxin G2，zearalenone，zearalanone，β-zearalanol，α-zearalanol，β-zearalenol，α-zearalenol and deoxynivalenol） in forage grass by means of solid supported liquid-liquid extraction（SLE） coupled with ultra high performance liquid chromatography-tandem mass spectrometry has been established. In this study，two pairs of mycotoxins epimers （β-zearalanol and α-zearalanol，β-zearalenol and α-zearalenol） were separated completely under optimized chromatographic conditions. The sample were extracted with 1% formic acid acetonitrile/water（8∶2），and then purified by a diatomaceous earth SLE cartridge. Series of experiment conditions such as the extraction solvent type and the volume of elution solvent was examined and optimized，6 mL ethyl acetate was the suitable elution solution. The matrix effects of mycotoxins in alfalfa，oats，leymus chinensis and silage corn were discussed，and the interference of matrix was reduced by the matrix matched calibration standards curve. Results showed good linearity（r2＞0.995） for determination of 11 mycotoxins. The limits of detection（LODs） and the limits of quantitation（LOQs） were in the ranges of 0.3 μg/kg to 20.3 μg/kg and 0.8 μg/kg to 51.4 μg/kg，respectively. Recoveries for 11 mycotoxins at three spiked levels ranged from 72.7% to 108% with relative standard deviations（RSDs） ranged from 3.4% to 8.1%. The method has the advantages of simple operation，good reproducibility and accurate，and the LOQ of method were lower than the specific migration limit specified in the regulation and standards. The proposed method has great potentials in the detection of mycotoxins in forage grass.关键词：mycotoxins;forage grass;solid supported liquid-liquid extraction;UPLC-MS/MS34|22|0更新时间：2025-03-17 -
摘要：To explore the relationship between tobacco strip online near-infrared spectra and cigarette brand identification，a cigarette brand classification method based on the ResNeXt18-CNN-LightGBM hybrid model is proposed. Firstly，the collected tobacco strip sample online spectral data are preprocessed，and the ResNeXt18 network model is used to extract initial features from the preprocessed spectra. Then，the extracted features are input into a custom 3-layer CNN network model for secondary feature extraction. Finally，the features extracted by the CNN are fed into a LightGBM classifier for brand classification training. The results show that the classification accuracy of tobacco strip brand identification in the ResNeXt18-CNN-LightGBM model reaches 97%. Compared with traditional single chemometrics algorithms，the proposed cigarette brand classification method based on a convolutional neural network combination algorithm is simple，accurate，and stable. It can be applied to the online identification of cigarette brands in cigarette manufacturing，with significant implications for cigarette brand management，production quality evaluation，and cigarette quality control.关键词：online near-infrared spectroscopy;cigarette brand;ResNeXt18;LightGBM;classification performance47|28|0更新时间：2025-03-17 -
摘要：Second harmonic generation（SHG） has been applied widely for label-free，low light toxicity and sensitive to structure. The conditions of SHG imaging on a two-photon microscope were explored by using in vivo mouse skin. Glycerol was used as a clearing agent. The SHG signal intensity and the imaging depth of the skin were statistically evaluated after glycerol and water treatments. The SHG signal intensity and imaging depth showed significant differences between the glycerol-treated and water-treated groups（* p≤0.05），suggesting that glycerol serves as an efficient clearing agent for in vivo skin studies. Through an exploration of laser performance（output power），the autofluorescence properties of biological tissues，and imaging depth，the optimal excitation wavelength for SHG imaging with a two-photon microscope was 900 nm. With the application of glycerol and the optimal excitation wavelength，SHG signals from tumor skin can be collected，allowing the study of effects of tumors on collagen fiber in vivo. The results show that the two-photon microscope can effectively perform SHG imaging and suitable for observation and visualization research of the collagen fiber structure within biological tissues.关键词：two-photon microscope;second-harmonic generation;tumor;collagen45|34|0更新时间：2025-03-17 -
摘要：The sorbent tube packing containing Tenax TA is widely used to detect volatile organic compounds（VOCs） in indoor air. But it's important to recognize that sample penetration can happen easily when sampling the low-boiling VOCs，which can seriously affect the accuracy of the data obtained. In this study，after gathering the typical low-boiling VOCs，the breakthrough curves and absorption rates of adsorption tubes packed with Tenax-TA and T-C composite were compared using adsorption-pyrolysis/gas chromatography. Additionally，employing T-C composite adsorption tubes for adsorption-thermal desorption/gas chromatography，the desorption rate，accuracy and precision of this method were also examined. These results showed that the T-C composite tube performed better in adsorbing VOCs with low boiling points than Tenax TA，which prevented sample penetration. Adsorption and desorption rates were not less than 98.4% and 99.7%，respectively. Furthermore，the calibration curves for target compounds were linear in the range of 0-2.00 μg with correlation coefficients not less than 0.997 4. And the average recoveries ranged from 95.7% to 112%，with relative standard deviations（RSDs） of 1.5%-6.3%. The previous results indicated that the T-C composite adsorption tube would be a useful tool for accurately identifying VOCs with low-boiling points from indoor air and decorative materials.关键词：low-boiling;volatile organic compounds（VOCs）;breakthrough;T-C composite adsorption tube;indoor air;gas chromatography35|31|0更新时间：2025-03-17 -
摘要：Due to the serious threat of heavy metal ions to human health，there is an urgent need for rapid and sensitive detection of heavy metal ions in the global natural water environment. This article develops a gold nanoparticle（AuNPs）-based label-free colorimetric sensor for simple，sensitive，and selective determination of silver ions（Ag+）. The sensing mechanism is attributed to ascorbic acid（AA） around AuNPs，which can produce strong interactions between AA and Ag+ and generate Au@AgNPs at pH 6.2，resulting in simultaneous increasement and blue shift of the surface plasmon resonance（SPR） band of AuNPs at 518 nm，while new peaks appear near 386 nm，accompanied by red-to-yellow color change. On this basis，the colorimetric sensor showed a good linear relationship between the absorbance change at 386 nm wavelength and the Ag+ concentration in the range of 0.4-1.4 μmol/L，with a detection limit as low as 0.115 μmol/L. In addition，the colorimetric sensor has good selectivity for Ag+ in presence of other interfering metal ions and can be successfully applied to the determination of Ag+ in wastewater.关键词：ascorbic acid;gold nanoparticles;colorimetry;sewer water;silver ions31|29|0更新时间：2025-03-17 - 摘要：In this paper，based on inductively coupled plasma mass spectrometry（ICP-MS） technology，a method for measuring the boron concentration in human whole blood was established. Whole blood samples were diluted directly with a mixture solution of 0.1% nitric acid and 0.1% Triton X-100，and the system applicability，quantitative range，precision and accuracy，matrix effect and so on of the method were verified. The results showed that the method has the quantitative range of 2-50 μg/mL for 10B and has good precision and accuracy and no matrix effect. This method has the characteristics of easy operation，rapid detection and usable data，and is suitable for real-time monitoring of 10B concentration in blood of patients during BNCT treatment.关键词：ICP-MS;blood boron concentration;boron neutron capture therapy（BNCT）;clinical30|13|0更新时间：2025-03-17
Experimental Techniques and Methods
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摘要：Infrared spectroscopy has gradually been applied in each link of baijiu brewing for its characteristics of non-destructive，simple，fast，and pollution-free，and it plays an important role in baijiu production process. In this paper，the development status of infrared spectroscopy and infrared spectrometers were introduced. The modeling process of infrared spectroscopy analysis in baijiu industry was summarized，as well as the chemometrics methods of infrared spectroscopy analysis currently applied to baijiu industry were summarized，and the chemometrics methods were classified and the application characteristics of each method were described. The application of infrared spectroscopy in raw and adjunct materials，jiuqu，jiupei，base baijiu，baijiu，yellow fermentation liquid，pit mud，and partial production process stage during baijiu brewing was reviewed. The problems in the existing research were summarized and analyzed，and the development direction of infrared spectroscopy in baijiu industry application for detection was prospected. Furthermore，it is proposed that improving or developing equipment or algorithm specially for baijiu industry to improve the accuracy of model prediction will be the focus of future research work. And combining the big data of baijiu production analyzed by infrared spectroscopy with artificial intelligence analysis would provide more technical references for the intelligence of baijiu brewing.关键词：baijiu brewing;infrared spectroscopy;chemometrics methods;rapid detection35|45|0更新时间：2025-03-17 -
摘要：Small extracellular vesicles（sEVs） play an important role in the process of cancer occurrence as well as development，and a large number of studies have explored cancer-related biomarkers in sEVs，mainly including sEVs membrane proteins and intramembranous miRNAs. The combined analysis of multiple markers can be used to provide multidimensional understanding of the information of sEVs，which can help to improve the accuracy of cancer screening and auxiliary diagnosis，and is crucial for enhancing the efficacy of oncology treatment and improving the prognosis. Most of the traditional protein and nucleic acid assays for analysing sEVs-related biomarkers required complex pre-processing and suffered from the shortcomings of time-consuming and low sensitivity. Emerging assays and technologies enable take rapid，highly sensitivity，high-throughput analysis of sEVs with smaller sample volumes and easier sample pre-treatment. In this paper，we mainly review the research progress of protein and miRNA detection methods for sEVs in terms of single-class target detection（proteins，miRNAs） and multi-class marker detection（simultaneous detection of sEVs proteins and miRNAs，etc.），besides，the problems faced by sEVs in clinical practice and the direction of future development are also summarized.关键词：small extracellular vesicles;miRNA detection;protein detection;multiplex detection38|30|0更新时间：2025-03-17
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