A metabolic map and artificial intelligence-aided identification of nasopharyngeal carcinoma via a single-cell Raman platform.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a complex cancer influenced by various factors. This study explores the use of single-cell Raman spectroscopy as a potential diagnostic tool for investigating biomolecular changes associated with NPC carcinogenesis. METHODS: Seven NPC cell lines, one immortalised nasopharyngeal epithelial cell line, six nasopharyngeal mucosa tissues and seven NPC tissue samples were analysed by performing confocal Raman spectroscopic measurements and imaging. The single-cell Raman spectral dataset was used to quantify relevant biomolecules and build machine learning classification models. Metabolomic profiles were investigated using ultra-performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS). RESULTS: By generating a metabolic map of seven NPC cell lines, we identified an interplay of altered metabolic processes involving nucleic acids, amino acids, lipids and sugars. The results from spatially resolved Raman maps and UPLC-MS/MS metabolomics were consistent, revealing an increase of unsaturated fatty acids in cancer cells, particularly in highly metastatic 5-8F and poorly differentiated CNE2 cells. The classification model achieved a nearly perfect classification when identifying NPC and non-NPC cells with an ROC-AUC of 0.99 and a value of 0.97 when identifying 13 tissue samples. CONCLUSION: This study unveils a complex interplay of metabolic network and highlights the potential roles of unsaturated fatty acids in NPC progression and metastasis. This renders further research to provide deeper insights into NPC pathogenesis, identify new metabolic targets and improve the efficacy of targeted therapies in NPC. Artificial intelligence-aided analysis of single-cell Raman spectra has achieved high accuracies in the classification of both cancer cells and patient tissues, paving the way for a simple, less invasive and accurate diagnostic test.

Improving regional medical laboratory center report quality through a report recall management system.

OBJECTIVES: Currently, most medical laboratories do not have a dedicated software for managing report recalls, and relying on traditional manual methods or laboratory information system (LIS) to record recall data is no longer sufficient to meet the quality management requirements in the large regional laboratory center. The purpose of this article was to describe the research process and preliminary evaluation results of integrating the Medical Laboratory Electronic Record System (electronic record system) laboratory report recall function into the iLab intelligent management system for quality indicators (iLab system), and to introduce the workflow and methods of laboratory report recall management in our laboratory. METHODS: This study employed cluster analysis to extract commonly used recall reasons from laboratory report recall records in the electronic record system. The identified recall reasons were validated for their applicability through a survey questionnaire and then incorporated into the LIS for selecting recall reasons during report recall. The statistical functionality of the iLab system was utilized to investigate the proportion of reports using the selected recall reasons among the total number of reports, and to perform visual analysis of the recall data. Additionally, we employed P-Chart to establish quality targets and developed a "continuous improvement process" electronic flow form. RESULTS: The reasons for the recall of laboratory reports recorded in the electronic recording system were analyzed. After considering the opinions of medical laboratory personnel, a total of 12 recall reasons were identified, covering 73.05 % (1854/2538) of the recalled laboratory reports. After removing data of mass spectra lab with significant anomalies, the coverage rate increased to 82.66 % (1849/2237). The iLab system can generate six types of statistical graphs based on user needs, including statistical time, specialty labs (or divisions), test items, reviewers, reasons for report recalls, and distribution of the recall frequency of 0-24 h reports. The control upper limit of the recall rate of P-Chart based on laboratory reports can provide quality targets suitable for each professional group at the current stage. Setting the five stages of continuous process improvement reasonably and rigorously can effectively achieve the goal of quality enhancement. CONCLUSIONS: The enhanced iLab system enhances the intelligence and sustainable improvement capability of the recall management of laboratory reports, thus improving the efficiency of the recall management process and reducing the workload of laboratory personnel.

Blood Biomarkers Panels for Screening of Colorectal Cancer and Adenoma on a Machine Learning-Assisted Detection Platform.

OBJECTIVE: A mini-invasive and good-compliance program is critical to broaden colorectal cancer (CRC) screening and reduce CRC-related mortality. Blood testing combined with imaging examination has been proved to be feasible on screen for multicancer and guide intervention. The study aims to construct a machine learning-assisted detection platform with available multi-targets for CRC and colorectal adenoma (CRA) screening. METHODS: This was a retrospective study that the blood test data from 204 CRCs, 384 CRAs, and 229 healthy controls was extracted. The classified models were constructed with 4 machine learning (ML) algorithms including support vector machine (SVM), random forest (RF), decision tree (DT), and eXtreme Gradient Boosting (XGB) based on the candidate biomarkers. The importance index was used by SHapely Adaptive exPlanations (SHAP) analysis to identify the dominant characteristics. The performance of classified models was evaluated. The most dominating features from the proposed panel were developed by logistic regression (LR) for identification CRC from control. RESULTS: The candidate biomarkers consisted of 26 multi-targets panel including CEA, AFP, and so on. Among the 4 models, the SVM classifier for CRA yields the best predictive performance (the area under the receiver operating curve, AUC: .925, sensitivity: .904, and specificity: .771). As for CRC classification, the RF model with 26 candidate biomarkers provided the best predictive parameters (AUC: .941, sensitivity: .902, and specificity: .912). Compared with CEA and CA199, the predictive performance was significantly improved. The streamlined model with 6 biomarkers for CRC also obtained a good performance (AUC: .946, sensitivity: .885, and specificity: .913). CONCLUSIONS: The predictive models consisting of 26 multi-targets panel would be used as a non-invasive, economical, and effective risk stratification platform, which was expected to be applied for auxiliary screening of CRA and CRC in clinical practice.

The Comparison of Biomolecular Changes of Epstein-Barr Virus Infection in Nasopharyngeal Epithelial Cells Using Confocal Raman Microspectroscopy.

BACKGROUND: Due to its unique fingerprinting properties, Confocal Raman microscopy (CRM) can be used to examine the biomolecular changes of viruses invading and manipulating host cells. Recently, the biochemical changes due to the invasion and infection of B lymphocyte cells, nerve cells, and epithelial cells by Epstein-Barr virus (EBV) have been reported. However, biomolecular changes in nasopharyngeal epithelial cells that result from EBV infection are still poorly understood. METHODS: In continuation of our prior investigation of EBV infection in nasopharyngeal epithelial cells, we tried to expound on biomolecular changes in EBV-infected nasopharyngeal epithelial cells using Raman microspectroscopy. EBV has two life cycles, latent infection and lytic replication. We have established latent and lytic infection models at the cellular level. In order to understand the characteristics of the two patterns of EBV infection, we used Raman spectroscopy to identify the changes in biomolecules of EBV latent cells (CNE2, CNE2-EBV) and lytic cells (NPEC1-BMI1-CN, NPEC1-BMI1-EBV). RESULTS: During latent infection, levels of glycogen, protein, and lipid molecules in the cell increased while levels of nucleic acid and collagen molecules decreased. Molecular levels of glycogen, proteins, and nucleic acids are reduced during lytic infection. We found that molecular levels of nucleic acid decreased during two different periods of infection, whereas levels of other biomolecules showed the opposite trend. Glycogen, proteins, lipids, nucleic acids, and other molecules are associated with alterations in cellular biochemical homeostasis. These changes correspond to unique Raman spectra in infected and uninfected cells associated with specific biomolecules that have been proven. These molecules are mainly responsible for cellular processes such as cell proliferation and apoptosis. The Raman signatures of these biomolecular changes depend on the different phases of viral infection. CONCLUSIONS: Therefore, by using CRM, it is possible to discern details in the progression of EBV infection in nasopharyngeal epithelial cells at the molecular level.

Performance evaluation of an automatic chemiluminescence immune platform for SARS-CoV-2 neutralizing antibody after vaccination in real world.

OBJECTIVE: Reliable high-throughput serological assays for SARS-CoV-2 antibodies present an important role in the strength and duration of immunity after vaccination. The study investigated the analytical and clinical performances of neutralizing antibodies (NTAb) assay by chemiluminescent (CLIA), and SARS-CoV-2 neutralizing antibody after vaccination in real world. METHODS: The analytical performances of CLIA for SARS-CoV-2 NTAb were evaluated, followed by the sensitivity and specificity identified with a PRNT test from 50 volunteers. Then, a cohort of vaccine recipients (n = 37) were tracked with SARS-CoV-2 NTAb assay at prior to vaccination, one, three and six months post two doses. In real world, a total of 737 cases were recruited from physical examination center in Shenzhen Luohu People's Hospital (from Jun to August 2021) to analyze vaccination status. RESULTS: Serological assays on the CLIA were found with excellent characteristics including imprecision, repeatability and linearity. Besides, it was robust to icterus, lipemia and hemolysis. The good sensitivity and specificity were obtained at 98% and 100%, respectively. NTAb results showed a high correlation with PRNT50 titers (r 0.61). Until July 2021, the BBIBP-CorV (76.3%) and Sinovac CoronaVac (20.5%) were the predominant vaccines injection in Shenzhen, China. Adolescent less than 18 years was the main unvaccinated group (52.1%). The seropositive rate of inactive SRAR-CoV-2 vaccines exceeded 97% after inoculation. The NTAb generated by Sinovac CoronaVac with the schedule of 0-56 days was found significantly lower than that by BBIBP-CorV (P < 0.001). The follow-up of NTAb changes in a cohort and the dynamic variation of NTAb in real world disclosed steep downward by almost three times for NTAb level occurred at three months post twice vaccinations. The seropositive ratio was at least 50% over 6 months. CONCLUSIONS: SARS-CoV-2 neutralizing antibodies assay show excellent analytical and clinical performances, and a high correlation with neutralizing activity. Anti-epidemic measures and the urgent trial of SARS-CoV-2 vaccine was calling for adolescents.

Dynamic observation of SARS-CoV-2 IgM, IgG, and neutralizing antibodies in the development of population immunity through COVID-19 vaccination.

BACKGROUND: Currently, mass vaccine inoculation against coronavirus disease-2019 (COVID-19) has been being implemented globally. Rapid and the large-scale detection of serum neutralizing antibodies (NAbs) laid a foundation for assessing the immune response against SARS-CoV-2 infection and vaccine. Additional assessments include the duration of antibodies and the optimal time for a heightened immune response. METHODS: The performance of five surrogate NAbs-three chemiluminescent immunoassay (CLIA) and two enzyme-linked immunosorbent assays (ELISAs)-and specific IgM and IgG assays were compared using COVID-19-vaccinated serum (n = 164). Conventional virus neutralization test (cVNT) was used as a criterion and the diagnostic agreement and correlation of the five assays were evaluated. We studied the antibody responses after the two-dose vaccine in volunteers up to 6 months. RESULTS: The sensitivity and specificity of five surrogate NAb assays ranged from 84% to 100%. Our cVNT results indicated great consistency with the surrogate assays. At 28 days after primary vaccination, the seropositivities of the NAbs, IgG, and IgM were 6%, 4%, and 13%, respectively. After the booster dose, seropositivities reached 14%, 65%, and 97%, respectively. Six months after receipt of the second dose, the NAb positive rate was eventually maintained at 66%. In all COVID-19 convalescents, patients were detected with 100% NAb sat three months after discharge. CONCLUSION: COVID-19 vaccine induced a humoral immune response lasting at least six months. Rapid serological detection was used as a proxy for identifying changes in immunity levels and as a guide to whether an individual may require a booster vaccination.

Comparison of three automatic chemiluminescent immunoassays for monitoring dynamic profile of SARS-CoV-2 IgG and IgM.

BACKGROUND: Seldom performance evaluation and diagnosis comparison studies were reported for different chemiluminescent immunoassay (CLIA) kits approved under an emergency approval program for SARS-CoV-2 infection. METHODS: A total of 100 and 105 serum separately from non-infected populations and COVID-19 patients were detected with SARS-CoV-2 IgM and IgG kits. The characteristics including precision, functional sensitivity, linearity, and accuracy were evaluated for Axceed, iFlash, and Maglumi CLIA kits. RESULTS: Maglumi and iFlash had the best analytical sensitivity for IgM and IgG, respectively. Axceed kits had a linearity response in the detected concentration. The clinical sensitivity of Axceed, iFlash, and Maglumi was 68.0%, 64.9%, and 63.9% with a specificity of 99.0%, 96.0%, and 100% for IgM, 85.6%, 97.9%, and 94.8% with a specificity of 97.0% for IgG. ROC analysis indicated all kits had a diagnostic power greater than 0.9. Notably, either IgM or IgG kits obtained a poor agreement (Kappa value from 0.397 to 0.713) with others. Among 38 recovered patients, 94.7% had an effective immune response, and both seropositive IgM and IgG accounted for the biggest proportion (medium, 42 days onset), then followed by the single seropositive IgG (medium, 50 days onset) in Ab profile. CONCLUSION: The performance of CLIA kits satisfied the diagnosis of SARS-CoV-2 infection. Both positive of IgG and IgM contributes to improve the specificity, and a positive one will enhance the sensitivity.

Analytical performance evaluation of five RT-PCR kits for severe acute respiratory syndrome coronavirus 2.

BACKGROUND: We aimed to evaluate the analytical performance of five commercial RT-PCR kits (Genekey, Daan, BioGerm, Liferiver, and Yaneng) commonly used in China, since such comparison data are lacking. METHODS: A total of 20 COVID-19 confirmed patients and 30 negative nasopharyngeal swab specimens were analyzed by five kits. The detection ability of five RT-PCR kits was evaluated with 5 concentration gradients diluted by a single positive sample. The limit of detection was evaluated by N gene fragment solid standard. Two positive clinical specimens were used to evaluate the repeatability and imprecision. Finally, we used six human coronaviruses plasmid and four respiratory pathogens plasmid to check for cross-reactivity. RESULTS: The positive detection rate was 100% for Genekey, Daan, and BioGerm,and 90% for Liferiver and Yaneng in 20 clinical SARS-CoV-2 infection. The coincidence rate of five kits in 10 negative samples was 100%. The detection rate of target genes for Daan, BioGerm, Liferiver, and Yaneng was 100% from Level 1 to Level 3. In Level 4, only Daan detection rate was 100%. In Level 5, five kits presented poor positive rate. The limit of detection declared by each manufacturer was verified. The repeatability for target genes was less than 5% and so did the total imprecision. There is no cross-reactivity of five kits with six human coronaviruses and four respiratory pathogens for ORF1ab and N gene. CONCLUSIONS: Five RT-PCR kits assessed in this study showed acceptable analytical performance characteristics and are useful tools for the routine diagnosis of SARS-CoV-2.

An integrated strategy for rapid on-site screening and determination of prometryn residues in herbs.

We produced a prometryn-specific monoclonal antibody and propose a strategy for convenient on-site detection of prometryn residues in herbs for the first time. This strategy has perfect applicability in a complex herbal medicine matrix. The strategy combines a semiquantitative immunochromatographic strip assay with a heterologous indirect competitive ELISA. When there was no matrix interference, the ELISA had a half-maximal inhibitory concentration of 2.6 ng·mL-1 and a limit of detection of 0.2 ng·mL-1. The immunochromatographic strip assay can be completed within 5 min with a visual limit of detection of 1 ng·mL-1. Although the sample matrix had different effects on the sensitivity of the antibody, excellent repeatability and accuracy were achieved. The method was successfully applied for the screening and determination of prometryn residue in multiple complex herb samples for the first time, and the results were in good agreement with those obtained by liquid chromatography-tandem mass spectrometry. The proposed strategy is rapid, of high-throughput, and of low cost, and may be a promising choice for on-site detection of prometryn in different kinds of herbs. Graphical abstract.

Consistency evaluation of Liferiver, Yaneng, Darui, and the Cobas 4800 test for high-risk human papillomavirus screening.

BACKGROUND: In recent years, several high-risk human papillomavirus (HR-HPV) tests have been developed. The assay capabilities need to be systematically reviewed. Here, we compared the clinical sample performance of three novel HR-HPV assays (Liferiver, Yaneng, and Darui) based on different platforms with the widely adopted cobas4800 test. METHODS: A total of 346 cervical swabs from women who were screened for cervical cancer were analyzed for the presence of 14 HR-HPV genotypes. The distinction between the four assays was investigated by the genotyping and direct sequencing. RESULTS: The positive rates of the four assays ranged from 61.56% to 64.16%. The overall concordance was 88.15%. The Yaneng assays displayed the best sensitivity (100%) and specificity (98.43%). The sensitivity (98.17%) and specificity (98.43%) of the Darui assay were superior to those of the cobas4800 test (97.72% and 93.70%, respectively). The Liferiver assay displayed comparable sensitivity with the cobas4800 test (95.89% and 97.72%, respectively). The specificity of the cobas4800 was lower than that of the Liferiver assay (93.70% vs. 97.64%). CONCLUSIONS: The three novel HR-HPV assays displayed good agreement with the cobas4800 test. The analytical performance of all four fulfilled the requirements of sensitivity and specificity for HR-HPV detection.

Oriented assembly of surface plasmon resonance biosensor through staphylococcal protein A for the chlorpyrifos detection.

In this study, we report a direct surface plasmon resonance (SPR) biosensor based on an oriented assembly of antibody for the rapid detection of chlorpyrifos residue in agricultural samples. In this covalent-orientated strategy, staphylococcal protein A (SPA) was first covalently bound to the surface for monitoring chlorpyrifos residue, with subsequent binding of the antibody in an orientated fashion via its fragment crystallizable (Fc) region. Consequently, the SPA-modified biosensor exhibited a satisfactory specificity and a low detection limit of 0.056 ng mL-1 for chlorpyrifos, with a linear detection range of 0.25-50.0 ng mL-1. Under optimal conditions, the sensor chip could be regenerated for at least 210 cycles. The results presented here indicate that the SPA-modified sensor chip can successfully improve the sensitivity and obviating the need of the modification of the antibody. The developed SPR biosensor method has the great potential for rapid, sensitive, and specific detection with broad applications in areas of environmental monitoring and food safety. Graphical abstract.

A gold/Fe3O4 nanocomposite for use in a surface plasmon resonance immunosensor for carbendazim.

A surface plasmon resonance (SPR) biosensor for the pesticide carbendazim is described that has enhanced performance due to the use of a Au/Fe3O4 nanocomposite as an amplifying label on the surface the carboxymethyldextran-coated gold layer of the sensor. The surface was further modified with monoclonal antibody to obtain a sensor for real-time detection of carbendazim. Binding of carbendazim results in a change in refractive index. SPR detection in the absence of Au/Fe3O4 nanocomposite and by UPLC-MS analysis demonstrated the improved performance to be due to the use of the Au/Fe3O4 nanocomposite. Response is linear in the 0.05 to 150 ng·mL-1 carbendazim concentration range, and the limit of detection is 0.44 ng·mL-1. This is more than 1 order of magnitude lower than that of the conventional SPR assay. The recoveries from spiked medlar are between 102.4 and 115.0%. The selectivity was tested by using the pesticides benzimidazole, 2-mercaptobenzimidazole, 2-benzimidazole propionic acid, and 2-(2-aminoethyl) benzimidazole as potential interferents. Conceivably, this Au/Fe3O4 nanocomposite-based method has a large potential for the detection of other small analytes at trace concentrations. Graphical abstract Schematic presentation of the SPR sensor for the detection of the fungicide carbendazim (methyl 2-benzimidazole carbamate; MBC) based on the use of a gold/Fe3O4 nanocomposites.

[High-throughput screening of ochratoxin A in Chinese herbal medicines using enzyme-linked immunoassay].

An indirect competitive enzyme-linked immunosorbent assay( ic-ELISA) was developed for the rapid detection of ochratoxin A( OTA) in nutmeg( Myristicae Semen),ginger( Zingiberis Rhizoma) and turmeric( Curcumae Longae Rhizoma). The matrix matching standard curve was used instead of the standard curve of sample diluent,and the sample extract and sample diluent were optimized. The sensitivity( IC_(50)) of this method for OTA in nutmeg,ginger and turmeric were determined as 0. 146,0. 157 and 0. 153 ng·m L~(-1),respectively and the limits of detection( LODs) were 0. 040,0. 032 and 0. 031 ng·m L~(-1),respectively. The recovery of samples ranged from 75. 99% to 122. 3%,with RSD<10%. Two positive samples for nutmeg and one positive sample for turmeric occurred in 50 samples,and the highest OTA contamination value was 1 167. 8 µg·kg~(-1). The results were further confirmed by LC-MS/MS. It shows that the developed ic-ELISA method is simple,rapid and sensitive,and can be applied for rapid and high-throughput screening of OTA in nutmeg,ginger and turmeric,as well as some other CHMs.

[Analysis and health risk assessment of aflatoxin B_1 residue in Ziziphi Spinosae Semen].

This study aimed to analyze the residues of aflatoxin B_1( AFB_1) in Ziziphi Spinosae Semen from different producing areas and to assess the health risk of aflatoxin B_1 residue based on the obtained data. A total of 72 samples of Ziziphi Spinosae Semen from different areas were detected by IAC-HPLC-FLD. Based on the data of AFB_1 pollution,a probabilistic assessment model with Monte Carlo simulation was developed. Then,the risk assessment of AFB_1 exposure by Ziziphi Spinosae Semen intake was carried out by MOE( margin of exposure). The results showed that 32 out of 72 of samples( 44. 4%) were found to be contaminated with AFB_1,and the average and maximum concentration of AFB_1 in samples was 5. 42 µg·kg~(-1) and 55. 09 µg·kg~(-1),respectively. After health risk assessment,the average and 97. 5%( 90% confidence interval) exposure level of daily exposure of AFB_1 by Ziziphi Spinosae Semen intake were 0. 008 6( 0. 008 1-0. 009 2) and 0. 057 3( 0. 053 2-0. 061 4) µg·kg~(-1)·d~(-1),respectively. The results showed common use of Ziziphi Spinosae Semen had low level of risk associated with AFB_1. However,the high consumption of Ziziphi Spinosae Semen showed a higher risk than common intake,requiring attention. This study laid a foundation for clinical safe prescription of Ziziphi Spinosae Semen.

[QuEchERS pretreatment coupled to gas chromatography and tandem mass spectrometry to fast determination of 34 pesticide residues in Glycyrrhizae Radix et Rhizoma].

This study proposed a quantitative method for 34 pesticides including organochlorine,organophosphorus and pyrethroids in Glycyrrhizae Radix et Rhizoma herbs and medicinal slices,and analyzed the pesticide residues of collected Glycyrrhizae Radix et Rhizoma samples from different regions. With acetonitrile extraction and optimized Qu Ech ERS purification,the 32 batches of Glycyrrhizae Radix et Rhizoma herbs and medicinal slices were analyzed by matrix matching standard curve quantitative analysis under GC-MS/MS multi-response monitoring( MRM) mode. This study investigated the pretreatment of Glycyrrhizae Radix et Rhizoma samples based on the Qu Ech ERS method of Chinese Pharmacopoeia( 2015 edition,4),and the result showed that the recoveries of some pesticide was low and pigment has a strong interference in analysis,which result in worse purification effect. Therefore,this paper further optimized the Qu Ech ERS method and corrected the matrix matching standard curve method,and compensated the qualitative and quantitative effects of matrix effects on the detected target compounds in Glycyrrhizae Radix et Rhizoma. The results showed that 34 kinds of pesticide had good linear( R~2 of 0. 996 4 or higher) within a covering 0. 01-0. 2 mg·kg~(-1) concentration range. The limits of quantitation are less than 0. 01 mg·kg~(-1). This method was further applied to the simultaneous determination of 34 pesticide residues of typical organochlorine,organophosphorus and pyrethroids in 32 batches of Glycyrrhizae Radix et Rhizoma herbs and medicinal slices. Six batches containing beta-endosulfan,thiosulphate,o,p'-DDD and thrta-cypermethrin were detected,but none of them exceeded the limit of pesticide residues stipulated in the Chinese Pharmacopoeia and the EU Pharmacopoeia. This study indicates that the established method is rapid,convenient,accurate,and sensitive,which provides a rapid and efficient method for the simultaneous determination of typical organochlorine,organophosphorus and pyrethroids in Glycyrrhizae Radix et Rhizoma.

Occurrence of multi-class mycotoxins in Menthae haplocalycis analyzed by ultra-fast liquid chromatography coupled with tandem mass spectrometry.

To determine the presence of multi-class mycotoxins in Menthae haplocalycis, a sample processing procedure based on a modified quick, easy, effective, rugged, and safe method, and a rapid and accurate testing method using ultra-fast performance liquid chromatography coupled with tandem mass spectrometry, was developed and validated. We systematically evaluated the methodology for multi-mycotoxin analysis in the Menthae haplocalycis samples, and chose matrix-matched calibration curves as a reference to calculate the recoveries. Overall, the average recoveries varied between 67.1 and 103%, with relative standard deviations ranging from 0.34 to 10.3%. The optimized and validated method was applied to detect the presence of the target mycotoxins in 40 batches of Menthae haplocalycis samples. Results showed that the levels of mycotoxins varied among the samples. The most prevalent mycotoxin was tentoxin, followed by alternariol, alternariol monomethyl ether, zearalenone, fumonisin B2 , fumonisin B1 , ochratoxin A, aflatoxin B1 , aflatoxin B2 , aflatoxin G1 , and T-2 toxin. The analytical method developed herein could be applied for the routine monitoring of multi-mycotoxins in Menthae haplocalycis.

[Identification and quality evaluation of Tripterygium wilfordii].

With the extensive clinical application of Tripterygium wilfordii, there are many counterfeit products on the market. Traditional technology can not effectively identify the authenticity of the traditional Chinese medicine. Therefore, a strategy of accurate identification and quality evaluation of Tripterygium based on DNA barcode and chemical fingerprint spectrum was established. Based on DNA barcode technology, HMMer annotation method of hidden Markov model and K2P model were used to analyze genetic distance.BLAST1, nearest distance and phylogenetic tree (NJ-tree) methods were used to assess the identification efficiency of the ITS2 barcode. The fingerprint of 27 T. wilfordii was established by UPLC-PDA method, and the similarity of the fingerprint of different sources was evaluated. The main components of T. wilfordii were determined by LC-MS/MS. The results revealed that the intraspecific genetic distances of T. wilfordii were lower than the interspecific genetic distances between T. wilfordii and its adulterants. The results of similarity search showed that ITS2 sequence was used to identify T. wilfordii and its adulterants. The clustering of T. wilfordii and its adulterants was clear in the tree of NJ cluster, and 12 of 27 samples were identified as true T. wilfordii.The chemical fingerprint spectrum research indicates that the feature one region can distinguish the false product of tripterygium glycosides more intuitively. The cluster analysis of HCA-thermal map showed that the contents of six active components of T. wilfordii from different habitats were significantly different, which could be used to evaluate the quality of T. wilfordii. This paper is of guiding significance for the accurate identification and quality evaluation of Tripterygium medicinal plants.

[Contamination distribution and control measures of aflatoxins in Chinese herbal pieces].

As an important part of traditional medicine in China, traditional Chinese medicine(TCM) plays a significant role because of its unique medical efficiency, less adverse reactions and extensive resources. However, in recent years, the aflatoxins in medicinal herbs have been detected excessive both at home and abroad, seriously affecting the reputation and credibility of traditional Chinese medicine. In this paper, the current status of aflatoxins contamination in medicinal herbs was analyzed, and the internal and external factors of aflatoxins contamination in traditional Chinese medicine were also summarized. In view of the high toxicity of aflatoxins, it is proposed to strengthen the mildew prevention and control from the early planting to storage stage, and the reasonable detoxification mode should also be considered. This review aims to provide a reference in guaranteeing the clinical safe administration of medicinal herbs and reducing the risk of being poisoned by aflatoxins.

Fluorometric competitive immunoassay for chlorpyrifos using rhodamine-modified gold nanoparticles as a label.

A new kind of labelled antibody was synthesized by modifying gold nanoparticles (AuNPs) with the fluorophore rhodamine B isothiocyanate (RBITC) and a secondary antibody (IgG). The conjugate thus obtained was used in a competitive sandwich assay with a turn-on signal change. It was designed to detect the organophosphorus pesticide chlorpyrifos. The fluorescence of the RBITC-labeled gold immunoprobe with emission at 575 nm and excitation at 556 nm is almost completely quenched. If, however, cysteamine is added, the fluorophore is released from the labeled secondary antibody and fluorescence increases in accordance with the quantity of secondary antibody bound to the sandwich. This assay was applied to determine chlorpyrifos in dried tangerine peels. The detection results were also independently confirmed by LC-MS/MS. The method allows the concentrations of chlorpyrifos to be quantified down to 4.9 ng·mL-1, which is equivalent to 61 µg·kg-1 in dried tangerine peels. In our perception, this approach has a wide potential to be applied in the determination of numerous analytes for which antibodies are available. Graphical abstract A new kind of labelled antibody was synthesized by modifying gold nanoparticles with fluorophore rhodamine B isothiocyanate (RBITC) and a secondary antibody (IgG). The conjugate was used in fluoroimmunoassay with a turn-on signal change. The method was designed to detect the organophosphorus pesticide chlorpyrifos.

[Advances on nanoparticles-tagged visual test strips for the rapid detection of pesticides].

The residue of the pesticides affects seriously the quality and safety of traditional Chinese medicine. Pesticide residue has caused ever-growing attention of people at home and abroad. Rapid detection techniques used for rapid screening of pesticide residues have expanded in a fast progress. As one of the fast development methods of rapid detection, visualization test strip based on nanoparticle has received much concern in recent years. This article focused on the classification of detection test strips and key factors on the fabrication of nanoparticle-based visualization test strips used in small molecule pesticides. Moreover, a wide application of nanoparticles-tagged test strips on pesticide residue was reviewed including single residue detection, multi residue detection, as well as quantitative analysis. Finally, the future application of visual test strip for detecting of pesticide residues in traditional Chinese medicine was forecasted, intending to provide the reference for rapid detection techniques on pesticide residues screening in herbal medicine industry.