Mechanistic investigation and dual-mode colorimetric-chemiluminescent detection of glyphosate based on the specific inhibition of Fe3O4@Cu nanozyme peroxidase-like activity.

In this study, a dual-mode colorimetric/CL nanosensor was developed for glyphosate detection based on the specific inhibition of Fe3O4@Cu peroxidase-like activity. Synthesized Fe3O4@Cu exhibited high levels of peroxidase-like activity that triggered the oxidation of luminol/3,3',5,5'-tetramethyl benzidine dihydrochloride (TMB) to excited-state 3-aminophthalic acid/blue oxTMB, thereby delivering a CL signal/visible colorimetric signal, however, the presence of glyphosate inhibited this activity, resulting in a decrease in signal strength. In-depth investigation revealed that this inhibitory mechanism occurs via two pathways: one in which glyphosate chelates with Fe(III)/Cu(II) and occupy the catalytical active sites of Fe3O4@Cu, thereby decreasing the generation of OH, and another in which glyphosate competes with TMB to consume generated OH, thus reducing the oxidation of TMB. This mechanism formed the basis of our novel dual-mode colorimetric/CL glyphosate nanosensor, which achieved limits of detection (LODs) of 0.086 µg/mL and 0.019 µg/mL in tests, thus demonstrating its significant potential for on-site glyphosate monitoring.

Diagnostic value of chemiluminescence for urinary lipoarabinomannan antigen assay in active tuberculosis: insights from a retrospective study.

Purpose: This study aimed to assess the efficacy of chemiluminescence-based urinary lipoarabinomannan (LAM) antigen assay as a diagnostic tool for identifying active tuberculosis. Methods: A retrospective study was conducted on 166 Tuberculosis (TB), 22 Non-Tuberculous Mycobacteria (NTM), 69 Non-TB cases, and 73 healthy controls from Zhangjiagang First Peoples Hospital between July 2022 and November 2022. Clinical and laboratory data were collected, including urine samples for LAM antigen detection, sputum samples and pleural effusion for GeneXpert, TB-DNA, and culture. Results: TB group exhibited a higher LAM positivity rate (P < 0.001). CD4 count and diabetes as independent factors influencing the diagnostic accuracy of LAM. The LAM assay showed a sensitivity of 50.6% and a specificity of 95.65%. Notably, LAM's sensitivity was superior to TB-DNA (50.60% vs. 38.16%, P < 0.05). LAM's PTB detection rate was 51.7%, superior to TB-DNA (P = 0.047). Moreover, in EPTB cases, the LAM detection rate was 42.11%, surpassing Gene Xpert (P = 0.042), as well as exceeding the detection rates of TB-DNA and sputum culture. Conclusion: LAM antigen detection using chemiluminescence has demonstrated outstanding clinical diagnostic value for active TB, especially in the diagnosis of extrapulmonary TB. The convenience of sample collection in this diagnostic approach allows for widespread application in the clinical diagnosis of active tuberculosis, particularly in cases of EPTB and sputum-negative patients.

Establishment and Evaluation of Recombinant Expression of HCV Transmembrane Protein (p7) and Detection of Anti-p7 Antibody in Serum of HCV-Infected Patients by Chemiluminescence.

OBJECTIVE: Our aim was to establish a chemiluminescence method for detecting anti-transmembrane protein (p7) antibody in the serum of patients with hepatitis C virus (HCV) infection. METHODS: The p7 gene was amplified by polymerase chain reaction using the plasmid PUC-p7 containing the p7 nucleic acid sequence of the HCV 1b genotype as the template, and recombinant plasmid pGEX-KG-p7 was constructed. After p7 fusion, the protein was induced and expressed in the prokaryote, extracted, and purified; the anti-p7 antibody detection kit was prepared, and its efficacy was evaluated. RESULTS: The plasmid pGEX-KG-p7 was constructed correctly, and p7 fusion protein was obtained. The methodological indexes of the kit, the precision test, blank limit and detection limit, etc, met the requirements. The positive rate of serum anti-p7 antibody in 45 patients with HCV infection was 20%. CONCLUSIONS: The kit can be used in screening diagnosis, condition monitoring, prognosis, and disease mechanism and epidemiological study of HCV infection. The p7 protein has immune response in HCV-infected patients.

Homing peptide combined with DNAzyme-based ELISA-like assay for highly specific and sensitive detection of fibrin.

A highly sensitive and specific ELISA-like chemiluminescence method for detection of fibrin has been developed. In the sensing platform, the homing peptide (CREKA), as recognition molecule, which can specially recognize the fibrin on microtiter plate, combined with G-quadruplex-based DNAzyme to form the probe of G-quadruplex-hemin DNAzyme-CREKA. After the sample solution was coated on the plates, the probe was crosslinked with fibrin through the interaction of CREKA and fibrin. Finally, luminol-H2O2 chemiluminesecence (CL) reaction was exploited for quantitative analysis of fibrin. The liner range for fibrin detection was from 0.112 pmol L-1 to 5.6 pmol L-1 with the detection limit of fibrin as low as 0.04 pmol L-1, based on a signal-to-noise ratio (S/N) of 3. Furthermore, on the basis of the high amplification efficiency of the rolling circle amplification (RCA) reaction, the method enabled to analyze fibrin with a detection limit corresponding to 0.06 fmol L-1, whose sensitivity increased 3 orders of magnitude than that of above method in the absence of RCA reaction. In particular, combined with the separation and washing steps of ELISA, the proposed method possessed higher selectivity, high-throughput and low cost, which shows promise for applications in clinical diagnosis.

Comparison of three methods to detect antibody response to SARS-CoV-2 vaccine / 中华微生物学和免疫学杂志

Objective:To detect IgG and neutralizing antibodies response to SARS-CoV-2 vaccine by comparing enzyme-linked immunosorbent assay (ELISA), commercial magnetic particle chemiluminescence assay(CLIA) and neutralization test(NT).Methods:ELISA, CLIA and NT were used to detect 143 healthy people before and after 28 days immunization with 2 doses of SARS-CoV-2 vaccine, and calculate the positive conversion rate, quantitative results and analysis the consistency of the three methods.Results:The positive conversion rate of SARS-CoV-2 vaccine antibody detected by ELISA, CLIA and NT were respectively 97.9%, 98.6% and 85.3%. The geometric mean of the highest dilution of the serum quantitatively detected by ELISA was 586.6; The mean of CLIA S/CO value was 11.26; The geometric mean titer of the NT was 7.6. The correlation coefficient between ELISA, CLIA and NT were respectively 0.69( P<0.01) and 0.65( P<0.01), and the correlation coefficient between ELISA and CLIA was 0.79( P<0.01). Conclusions:The three methods all detected high levels of antibodies response to SARS-CoV-2 vaccine immunization. ELISA and CLIA are more consistent to detect IgG antibody, and have a good correlation with the quantitative detection results of the NT.

Usefulness of serum opsonic activity measured by chemiluminescence method to assess the invasiveness of colorectal endoscopic mucosal dissection.

Endoscopic sub-mucosal dissection (ESD) is considered as a low-invasive treatment for early-stage colorectal cancer, but the degree of invasiveness has not been well investigated. The aim of this study was to evaluate the physical stress due to colorectal ESD based on changes in serum opsonic activity (SOA). SOA was examined by measuring reactive oxygen species (ROS) produced by neutrophils using lucigenin-dependent chemiluminescence (LgCL) and luminol-dependent chemiluminescence (LmCL). Sixty-nine patients were enrolled into the study and examined SOA in the morning of the day of ESD, the next day, and at four days after ESD. The peak height (PH) and area under the curve (AUC) of LgCL showed no significant difference between the day and the next day, whereas the PH and AUC for LgCL were significantly higher four days after ESD than on the day of ESD (p < .05). In contrast, the PH and AUC of LmCL showed no significant changes during the ESD perioperative period. This difference suggests that SOA changes during the colorectal ESD perioperative period involved minor increases in the production of lower-toxicity ROS. This finding supports the position that ESD is a technique that does not generate a great deal of physical stress. On the other hand, a significant increase in SOA at four days after colorectal ESD suggests that care is needed with postoperative management even after the patient has started to eat meals again.

A novel ECL method for histone acetyltransferases (HATs) activity analysis by integrating HCR signal amplification and ECL silver clusters.

A novel electrogenerated chemiluminescence (ECL) method combining ECL property of silver clusters and hybridization chain reaction (HCR) signal amplification strategy has been designed for the analysis of histone acetyltransferases (HATs) activity and inhibitor evaluation. In this strategy, the substrate peptide of HAT released from the electrode surface due to the charge change based on the acetylated reaction in the presence of HATs, and then the exposed DNA on the electrode initiated the HCR to form the supersandwich DNA sequence, which can adsorb Ag+, and the silver clusters (AgNCs) generated by the electrochemical reduction. The ECL signal generated by AgNCs can be utilized for HATs activities detection. The detection limit of the as-prepared ECL method was 0.49 nM (S/N = 3). The novel ECL method can be used for HATs activity analysis and inhibition in MCF-7 cell lysates which shows high promise in HATs-related clinical diagnostics.

Analysis on diseases interfering treponema pallidum antibody detection by chemiluminescence / 国际检验医学杂志

Objective To explore the interference situation of several diseases in the detection of treponema pallidum antibody by chemiluminescence method.Methods One hundred and ten samples of 9 kinds of different infectious diseases and 200 clinical random samples were collected.Three hundreds and ten samples were simultaneously detected by using the Abbott ARCHITECT i2000 automatic chemiluminescence immunoassay analyzer and matched reagents,and the Roche E602 automatic chemiluminescence instrument and its matching reagent.The samples of inconsistent results were confirmed by the gelatin particle agglutination test (TPPA).Results There were 5 samples with inconsistent results detected by two instruments,5 samples confirmed by TPPA were negative,and 4 cases were the samples of multiple myelome.Conclusion (1)Abbott ARCHITECT i2000 and Roche E602 have a good consistency in detecting treponema pallidum antibody;(2)for the patients of multiple myeloma,the interference may exist in detecting treponema pallidum antibody by chemiluminescence method,which may cause false positive results and needs to be vigilant in our daily work.

Establishment of Detection Limit and Clinical Reportable Range for Detection of Anti-HBs by Chemiluminescence Method / 现代检验医学杂志

Objective To establish detection limit and clinical reportable range for detection of anti-HBs by chemiluminescence method and evaluate by clinical application.Methods Referring to the Clinical and Laboratory Standards Institute (CLSI) relevant documents,the programme of blank limit (LoB),detection limit (LoD),quantitative detection limit (LoQ),analytical range of measurement (AMR),clinical reportable range (CRR) for detection of anti-HBs by chemiluminescence method,were designed and measured.The established clinical reportable range and maximum dilution were used to predict the recovery stage of acute hepatitis B patients and to evaluate the effectiveness of different vaccines.Results LoB,LoD,LoQ,AMR and CRR for detection of anti-HBs by chemiluminescence method were 0.87,1.89,3.0,0～970.50 and 3.0 ～48 525 mIU/ml respectively,and the maximum dilution was 1 ∶ 50.The patient with acute hepatitis B showed elevated anti-HBs at fourth weeks after treatment (CRR).The anti-HBs mean was the highest in the B vaccine of the three vaccines.Conclusion The establishment of detection limit and clinical reportable range for detection of anti-HBs by chemiluminescence method was better meet the requirements of clinical laboratories,provide reliable results for clinical laboratories.

Evaluate Performance of the Self-made Quality Control Products for C Peptide by Mixed Serums / 现代检验医学杂志

Objective When detecting the blood C peptide by chemiluminescence method,used had confronted the lack of qual-ity control.This paper examines the feasibility of self-made C peptide quality control as indoor quality control products. Methods From the serum of diabetic patients and health examination,C peptide low values(concentration around the 1.20 ng/ml)and high value(concentration around the 12.0 ng/ml)were collected,excluding hemolysis,jaundice and tallow ser-um,preventing bacterial contamination,hepatitis B surface antigen,hepatitis C virus,human immunodeficiency virus indica-tors are negative;then these serum was mixed respectively,embalmed,packaged,-20 DEG preserved.The performance e-valuation of the C peptide mixed serum was carried out using SIEMENS’s C peptide reagent kit.Results Low value,high value of two levels of serum C peptide quality control in batch imprecision respectively were 4.46% and 4.15% respective-ly.Day not precision respectively were 6.00%,5.56%,-20 DEG saved stability for at least 6 months (P>0.05).Com-pared with six months by analysis of variance,F value of the low and high values were 0.665,0.602,P values were 0.471, 0.568 and the difference was not statistically significant (P>0.05),but the difference among bottles was no significant. Conclusion Two levels value of the C peptide in self-made preserved at -20 DEG can meet the requirements of internal quality control products.

Methodological comparison on two kinds of method for detecting serum human epididymis protein 4 and bias evaluation / 国际检验医学杂志

Objective To compare the performance of 2 kinds of quantitative detection method the chemiluminescence immu-moassay and the enzyme-linked immunosorbent assay(ELISA)for detecting serum human epididymis geneproduct 4(HE4),and to explore the accuracy and practical value of the two methods.Methods In accordance to the document EP9-A2 of NCCLS,the Roche automatic electrochemical immunoassay system as the comparative method(X)and the ELISA as the testing method(Y )were per-formed according to the requirements of the detection kits.Results The serum HE4 level could be accurately reflected by the two methods.The correlation coefficient(r)in comparing these two kinds of method was ≥0.975,which showed that there was a high correlation between them.The detection results of the two methods were compared by paired sample t-test,and no statistically sig-nificant difference was found between them(P >0.05).Conclusion Because of CLIA′88 giving no specific medical decision level of HE4 and clinical acceptable level,therefore the expected bias of credibility interval can not be calculated or whether being clinically acceptable is unable to be judged.Based on the comparison of paired sample t test,these two kinds of detection methods can be used interchangeably to a certain extent.

Nucleic acid detection technology used in blood screening of blood donors / 国际检验医学杂志

Objective To evaluate the necessity and feasibility of nucleic acid test for donors blood screening .Methods From July 1 ,2011 to December 31 ,2014 ,a total of 170 316 blood samples which were negative in enzyme-linked immunosorbent assay (ELISA)and qualified in aianine aminotransferase detection ,were selected in this study stochastically .All the samples were detected hepatitis B virus(HBV) ,hepatitis C virus(HCV) ,human immunodeficiency virus(HIV) by nucleic acid amplification technology (NAT) .NAT positive samples were reconfirmed in National Center for Clinical Laboratories(NCCL) .Results A total of 160 cases of nucleic acid reactive samples were found out ,the total response rate was 0 .09% ,The response rate of Roche nucleic acid detec-tion system was 0 .10% ,response rate of David nucleic acid detection system was 0 .08% ,there was no significant difference be-tween the two methods(P>0 .05) .In 27 cases of specimens ,14 cases were confirmed as HBV DNA positive ,no HCV RNA and HIV RNA were detected ,the confirmed positive rate was 51 .85% .There were 2 samples detected by chemiluminescence HBsAg reactivity .Conclusion ELISA screening of blood donors has missing phenomenon ,nucleic acid detection method could be used as an effective supplement of the ELISA ,could improve the safety of blood for clinical use ,detection sensitivity is better than ELISA .

A relação entre os níveis séricos de CA 125 e o grau de diferenciação em neoplasias ovarianas / The relationship between serum levels of CA 125 and the degree of differentiation in ovarian neoplasms

Introduction: Primary ovarian neoplasms exhibit a wide range of histopathological aspects, and tumors with epithelial differentiation are the most frequent. Among the malignant tumors, the most common histological type corresponds to serous adenocarcinoma, whose diagnosis is established in advanced stages of the disease in approximately 75% of the patients. Tumor marker CA 125 represents a glycoprotein synthesized mainly by neoplastic cells with epithelial differentiation, and its serum level seems to be associated with the biological potential of these lesions. Objective: To estimate the association between serum levels of CA 125 and the degree of differentiation in primary ovarian neoplasms. Method: Sixty distinct cases of primary ovarian tumors were selected, previously analyzed at the Laboratory of Pathology of the Hospital Complex of Universidade Luterana do Brasil (Ulbra), between 2005 and 2010, from patients undergoing concomitant analysis of CA 125. In each case, age, tumor size, histological type, degree of differentiation, presence of necrosis and tumor invasion of the albuginea or extraovarian tissues, pathological stage and serum CA 125 were determined. Results: A statistically significant relationship between CA 125 levels and histological grade (p = 0.001), age (p = 0.009), biological behavior of the tumor (malignant or benign - p = 0.002) and extraovarian invasion (p = 0.005) was found. No relationship between CA 125 levels and tumor size (p = 0.1006) and pathologic stage (p = 0.1) was determined. Histologic grade was associated with the presence of necrosis (p = 0.001), extraovarian invasion (p = 0.009) and tumor size (p = 0.008). Conclusion: In the present study, serum levels of CA 125 were associated with histological grade in primary ovarian neoplasms, especially in high-grade malignant tumors, suggesting that high levels of this glycoprotein are associated with lesions of more aggressive biological behavior...

Introdução: As neoplasias primárias de ovário apresentam uma ampla variação dos aspectos histomorfológicos; sendo os tumores com diferenciação epitelial os mais frequentes. Entre os tumores malignos, o tipo histológico mais comum é o adenocarcinoma seroso, cujo diagnóstico é determinado em estágios avançados de doença em aproximadamente 75% das pacientes. O marcador tumoral CA 125 corresponde a uma glicoproteína sintetizada pelas células neoplásicas com diferenciação epitelial principalmente, e seu nível sérico parece estar associado ao potencial biológico dessas lesões. Objetivo: Estimar a associação entre o nível sérico de CA 125 e o grau de diferenciação em neoplasias ovarianas primárias. Método: Foram selecionados 60 casos distintos de tumores ovarianos primários, previamente analisados entre 2005 e 2010, de pacientes submetidas à dosagem sérica concomitante do marcador CA 125. Em cada caso foram determinados tamanho tumoral, tipo histológico, grau de diferenciação, presença de necrose tumoral, invasão neoplásica da albugínea ou tecidos extraovarianos, estadiamento patológico e nível sérico de CA 125. Resultados: Foi encontrada uma relação estatisticamente significativa entre nível de CA 125 e grau histológico (p = 0,001), idade (p = 0,009), comportamento biológico da neoplasia (maligno ou benigno - p = 0,002) e invasão extraovariana (p = 0,005). Não foi observada relação do nível de CA 125 com o tamanho tumoral (p = 0,1006) e o estadiamento patológico (p = 0,1). O grau histológico esteve associado à presença de necrose (p = 0,001), invasão extraovariana (p = 0,009) e ao tamanho tumoral (p = 0,008).Conclusão: Os níveis séricos de CA 125 estiveram associados ao grau histológico em neoplasias primárias ovarianas, principalmente nos tumores malignos de alto grau, sugerindo que os níveis elevados dessa glicoproteína estejam associados a lesões de comportamento biológico mais agressivo...

Application of immunofluorescence measured troponin I / 国际检验医学杂志

Objective To explore the clinical application of determination of troponin I(cTnI) by enzyme linked fluorescent(EL-FA) method .Methods The concentration of cTnI in serum was detected by chemiluminescence immunoassay(CLIA) method and ELFA method .The precision test ,linear test ,recovery test and interference test were done on ELFA method .The correlation analy-sis was done on the results of cTnI detected by ELFA method and CLIA method .Results Determination of the concentration of cTnI by ELFA method ,the intraassay coefficient of variation(CV) of high(30 .00 μg/L cTnI) and low (0 .12 μg/L cTnI) values were 2 .81% and 1 .62% ,the interassay CV were 5 .67% and 3 .52% .Reliable detection range detection of ELFA method was 0 .00-30 .00 μg/L .When the total bilirubin concentration less than 450μmol/L ,hemoglobin concentration less than 1 .5 g/L ,three glycerol concentration less than 7 .0 mmol/L ,the ELFA method for the determination of cTnI was without interference .Determina-tion of the concentration of cTnI had a good correlation between ELFA method and CLIA method(r=0 .971) .Conclusion The EL-FA method has good precision ,recovery and linear range ,and has a good correlation with the CLIA method ,and the ELFA method is rapid and convenient ,suitable for the emergency inspection ,can satisfy the clinical requirements .

Investigation of in vitro antioxidant activity of ginkgo albumin by chemiluminescence method / 中草药

Objective To investigate the scavenging abilities of ginkgo albumin to reactive oxygen in vitro, as well as the protection and mechanism of ginkgo albumin on damaged DNA. Methods Lotus Seedpod Procyanidin (LSPC) and bovine serum albumin (BSA) were used as control sample, the effect of ginkgo albumin on removal of superoxide anion was determined by Pyrogallol-Luminol system. Scavenging ability of ginkgo albumin on hydroxide free radical was determined by CuSO4-Phen-Vc-H2O2, FeSO4-Luminol-H2O2, and FeSO4-Luminol systems. Luminol-H2O2 system was used to measure the scavenging effect on hydrogen peroxide. Preventive effect of ginkgo albumin on in vitro damaged DNA was determined by CuSO4-Phen-Vc-H2O2-DNA system. Results Ginkgo albumin possessed a good scavenging potency on reactive oxygen and protection on damaged DNA, but promoted oxidation in the FeSO4-Luminol-H2O2 and Luminol-H2O2 chemiluminescence systems. Conclusion Not every chemiluminescences system is suitable for investigating the antioxidant activity of ginkgo albumin.

DETERMINATION OF FLAVONOIDS IN HAWTHORN FRUITS AND THEIR ANTIOXIDATION EFFECT / 营养学报

Objective: To extract and determine the flavonoids of hawthorn fruits and their antioxidative effect. Method: The ultrasonic method was used for extracting flavonoids. The content of flavonoids was determined by spectrophotometry, and the antioxidation effect was determined by flow-injection chemiluminescence.. Results and Conclution: The recovery rate was 96%～105% and the coefficient of variation was 0.14 % by spectrophotometry. Hawthorn fruits had high antioxidative effect, showing dose-response relation.