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1.
Luminescence ; 39(5): e4775, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38745525

RESUMO

A new smartphone-based chemiluminescence method has been introduced for the quantitative analysis of CL-20 (Hexanitroazaisowuertzitan) explosive. The solvent mixture, oxidizer agent, and concentration of the reactants were optimized using statistical procedures. CL-20 explosive showed a quenching effect on the chemiluminescence intensity of the luminol-NaClO reaction in the solvent mixture of DMSO/H2O. A smartphone was used as a detector to record the light intensity of chemiluminescence reaction as a video file. The recorded video file was converted to an analytical signal as intensity luminescence-time curve by a written code in MATLAB software. Dynamic range and limit of detection of the proposed method were obtained 2.0-240.0 and 1.1 mg⋅L-1, respectively, in optimized concentrations 1.5 × 10-3 mol⋅L-1 luminol and 1.0 × 10-2 mol⋅L-1 NaClO. Precursors TADB, HBIW, and TADNIW in CL-20 explosive synthesis did not show interference in measurement the CL-20 purity. The analysis of CL-20 spiked samples of soil and water indicated the satisfactory ability of the method in the analysis of real samples. The interaction of CL-20 molecules and OCl- ions is due to quench of chemiluminescence reaction of the luminol-NaClO.


Assuntos
Medições Luminescentes , Luminol , Smartphone , Medições Luminescentes/métodos , Medições Luminescentes/instrumentação , Luminol/química , Substâncias Explosivas/análise , Luminescência , Limite de Detecção
2.
Food Chem ; 451: 139461, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38701733

RESUMO

Copper as a widely applied element in food supply chain can cause serious contamination issues that threats food safety. In this research, we present a quick and visible method for trace copper ion (Cu2+) quantification in practical food samples. Polymer dots (Pdots) were firstly conjugated with a copper-specific DNA aptamer and then tailored with rhodamine B (RhB) to extinguish the electrochemiluminescence (ECL) signal through a resonance energy transfer process. The selective release of RhB leads to signal restoration when exposed to trace Cu2+ levels, achieving remarkable linearity with the logarithm of Cu2+ concentration within the range of 1 ng/L to 10 µg/L with an impressively low limit of detection at 11.8 pg/L. Most notably, our device was also applicable on visualizing and quantifying trace Cu2+ (∼0.2 µg/g) in practical Glycyrrhiza uralensis Fisch. samples, underscoring its potential as a tool for the early prevention of potential copper contamination in food samples.


Assuntos
Cobre , Técnicas Eletroquímicas , Contaminação de Alimentos , Medições Luminescentes , Cobre/análise , Cobre/química , Contaminação de Alimentos/análise , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Técnicas Eletroquímicas/instrumentação , Limite de Detecção , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Análise de Alimentos/métodos , Aptâmeros de Nucleotídeos/química , Pontos Quânticos/química
3.
Food Chem ; 452: 139549, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38762939

RESUMO

The prevention of pollution requires real-time monitoring of cadmium (Cd2+) concentration in the food, as it has a dramatic impact on poultry and can pose a threat to human health. Here, we fabricate a portable workstation integrating a microfluidic chip that facilitates real-time monitoring of Cd2+ levels in real samples by utilizing the Luminol-KMnO4 chemiluminescence (CL) system. Interestingly, Cd2+ can significantly enhance the CL signal, resulting in sensitive detection of Cd2+ in the range of 0-0.18 mg/L with the limit of detection (LOD) of 0.207 µg/L. Furthermore, a remote-controlled unit is integrated into the portable workstation to form a remote-controlled portable workstation (RCPW) performing automated point-of-care testing (POCT) of Cd2+. The as-prepared strategy allows remote control of RCPW to avoid long-distance transportation of samples to achieve real-time target monitoring. Consequently, this system furnishes RCPW for monitoring Cd2+ levels in real samples, thereby holding potential for applications in preventing food pollution.


Assuntos
Cádmio , Contaminação de Alimentos , Limite de Detecção , Medições Luminescentes , Cádmio/análise , Contaminação de Alimentos/análise , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Animais , Luminescência , Testes Imediatos
4.
Biosens Bioelectron ; 257: 116322, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38678789

RESUMO

Electrochemiluminescence (ECL) is a bioanalytical technique with numerous advantages, including the potential for high temporal and spatial resolution, a high signal-to-noise ratio, a broad dynamic range, and rapid measurement capabilities. To reduce the complexity of a multi-electrode approach, we use a single-electrode electrochemiluminescence (SE-ECL) configuration to achieve the simultaneous emission and detection of multiple colors for applications that require multiplexed detection of several analytes. This method exploits intrinsic differences in the electric potential applied along single electrodes built into electrochemical cells, enabling the achievement of distinct colors through selective excitation of ECL luminophores. We present results on the optimization of SE-ECL intensity for different channel lengths and widths, with sum intensities being 5 times larger for 6 cm vs. 2 cm channels and linearly increasing with the width of the channels. Furthermore, we demonstrated for the first time that applying Alternating Current (AC) voltage within the single electrode setup for driving the ECL reactions has a dramatic effect on the emitted light intensity, with square waveforms resulting in higher intensities vs sine waveforms. Additionally, multiplexed multicolor SE-ECL on a 6.5 mm × 3.6 mm CMOS semiconductor image sensor was demonstrated for the first time, with the ability to simultaneously distinguish four different colors, leading to the ability to measure multiple analytes.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Desenho de Equipamento , Medições Luminescentes , Técnicas Biossensoriais/instrumentação , Medições Luminescentes/instrumentação , Técnicas Eletroquímicas/instrumentação , Miniaturização , Cor , Eletrodos , Semicondutores , Humanos
5.
Mikrochim Acta ; 189(2): 79, 2022 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-35094170

RESUMO

3D-printed portable devices have immense and proven potential to transform the field of electrochemiluminescence (ECL) for diverse biochemical applications. 3D printing (3DP) offers unparalleled ability to build tiny devices in a single step with high accuracy and compatibility, and integrability as per the requirement. In this study, for the first time, a six-well 3D-printed closed bipolar electrochemiluminescence (3DP-CBPE-ECL) device has been successfully fabricated and validated by performing single-step detection of various biochemicals such as glucose and choline. Luminol/H2O2-based enzymatic reactions were performed with optimized parameters for selective sensing of glucose and choline. The single-step detection of glucose and choline was accomplished for the linear ranges of 0.1 to 10 mM and 0.1 to 5 mM, with a limit of detections (LODs) of 24 µM and 10 µM, respectively. A smartphone was leveraged to execute multiple activities such as powering the ECL device, capturing ECL images, and calculating the ECL intensity of the obtained ECL signal. The feasibility of a six-well 3DP-CBPE-ECL device was tested by sensing glucose and choline simultaneously in a single device at three different concentrations. Furthermore, the concentration of glucose and choline was calculated in real blood serum using the conventional additive (spiking) method, demonstrating the high practicability of the fabricated ECL device and yielding promising findings. Finally, based on the obtained results and other advantages such as low-cost, fast prototyping and requirement of a minimum sample volume, the fabricated six-well 3DP-CBPE-ECL device has shown potential to be used in the field of biochemical applications.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Medições Luminescentes/instrumentação , Impressão Tridimensional , Smartphone , Software , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Sistemas Automatizados de Assistência Junto ao Leito
6.
Mikrochim Acta ; 188(11): 398, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34716815

RESUMO

A simple carbon nanodot-based electrogenerated chemiluminescence biosensor is described for sensitive and selective detection of microRNA-21 (miRNA-21), a biomarker of several pathologies including cardiovascular diseases (CVDs). The photoluminescent carbon nanodots (CNDs) were obtained using a new synthesis method, simply by treating tiger nut milk in a microwave reactor. The synthesis is environmentally friendly, simple, and efficient. The optical properties and morphological characteristics of the CNDs were exhaustively investigated, confirming that they have oxygen and nitrogen functional groups on their surfaces and exhibit excitation-dependent fluorescence emission, as well as photostability. They act as co-reactant agents in the anodic electrochemiluminescence (ECL) of [Ru(bpy)3]2+, producing different signals for the probe (single-stranded DNA) and the hybridized target (double-stranded DNA). These results paved the way for the development of a sensitive ECL biosensor for the detection of miRNA-21. This was developed by immobilization of a thiolated oligonucleotide, fully complementary to the miRNA-21 sequence, on the disposable gold electrode. The target miRNA-21 was hybridized with the probe on the electrode surface, and the hybridization was detected by the enhancement of the [Ru(bpy)3]2+/DNA ECL signal using CNDs. The biosensor shows a linear response to miRNA-21 concentration up to 100.0 pM with a detection limit of 0.721 fM. The method does not require complex labeling steps, and has a rapid response. It was successfully used to detect miRNA-21 directly in serum samples from heart failure patients without previous RNA extraction neither amplification process.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Substâncias Luminescentes/química , Medições Luminescentes/métodos , MicroRNAs/sangue , Pontos Quânticos/química , Técnicas Biossensoriais/instrumentação , Carbono/química , Complexos de Coordenação/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Ouro/química , Insuficiência Cardíaca/sangue , Humanos , Ácidos Nucleicos Imobilizados/genética , Limite de Detecção , Medições Luminescentes/instrumentação , Masculino , MicroRNAs/genética , Hibridização de Ácido Nucleico , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/genética , Compostos de Rutênio/química
7.
Vet Res ; 52(1): 124, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593042

RESUMO

The parasitic gastrointestinal nematode Haemonchus contortus causes serious economic losses to agriculture due to infection and disease in small ruminant livestock. The development of new therapies requires appropriate viability testing, with methods nowadays relying on larval motility or development using procedures that involve microscopy. None of the existing biochemical methods, however, are performed in adults, the target stage of the anthelmintic compounds. Here we present a new test for the viability of H. contortus adults and exsheathed third-stage larvae which is based on a bioluminescent assay of ATP content normalized to total protein concentration measured using bicinchoninic acid. All the procedure steps were optimized to achieve maximal sensitivity and robustness. This novel method can be used as a complementary assay for the phenotypic screening of new compounds with potential antinematode activity in exsheathed third-stage larvae and in adult males. Additionally, it might be used for the detection of drug-resistant isolates.


Assuntos
Trifosfato de Adenosina/uso terapêutico , Hemoncose/veterinária , Haemonchus/isolamento & purificação , Medições Luminescentes/veterinária , Técnicas de Diagnóstico Molecular/veterinária , Doenças dos Ovinos/diagnóstico , Animais , Feminino , Hemoncose/diagnóstico , Hemoncose/parasitologia , Haemonchus/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Medições Luminescentes/instrumentação , Masculino , Técnicas de Diagnóstico Molecular/instrumentação , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
8.
Biochem Biophys Res Commun ; 577: 64-70, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34507067

RESUMO

To detect a small amount of Period1 (Per1) expression, we developed a micro-photomultiplier tube (µPMT) system which can be used both in vivo and in vitro. Using this system, we succeeded in detecting Per1 gene expression in the skin of freely moving mice over 240 times higher compared with that of the tissue contact optical sensor (TCS) as previously reported. For in vitro studies, we succeeded in detecting elevated Per1 expression by streptozotocin (STZ) treatment in the scalp hairs at an early stage of diabetes, when glucose content in the blood was still normal. In addition, we could detect elevated Per1 expression in a single whisker hair at the time of diabetes onset. These results show that our µPMT system responds to minute changes in gene expression in freely moving mice in vivo and in mice hair follicles in vitro. Furthermore, Per1 in the hair can be used for a marker of diabetic aggravation.


Assuntos
Expressão Gênica , Luciferases/genética , Medições Luminescentes/métodos , Proteínas Circadianas Period/genética , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Cabelo/metabolismo , Luciferases/metabolismo , Medições Luminescentes/instrumentação , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Atividade Motora/fisiologia , Movimento/fisiologia , Proteínas Circadianas Period/metabolismo , Reprodutibilidade dos Testes , Couro Cabeludo/metabolismo , Pele/citologia , Pele/metabolismo , Vibrissas/metabolismo
9.
J Med Virol ; 93(11): 6309-6316, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34375007

RESUMO

Serological tests detecting antibodies for Epstein-Barr virus (EBV) antigens are frequently used to define infection status. Several new automated assays are available for this purpose. We compared the performance of Architect, Immulite, Vidas, and Euroimmune immunofluorescence assays (IFA)/enzyme-linked immunosorbent assays (ELISA) for the detection of EBV viral capsid antigen (VCA) immunoglobulin M (IgM), VCA IgG, Epstein-Barr nuclear antigen (EBNA)-1 IgG. The routine diagnosis of EBV in our laboratory is done by anti-EBV VCA IgM IFT, anti-EBV VCA IgG IFT, and anti-EBNA-1 IgG ELISA (Euroimmune) Kits. Samples were tested with EBV Kits of Architect, Immulite, and Vidas for anti-VCA IgM, anti-VCA IgG, and anti-EBNA-1 IgG. The agreement between assays was calculated for each marker individually and for the determination of the EBV infection profile, based on the combination of three markers. BIOCHIP Sequence EBV (Avidity test) and/or EUROLINE EBV Profile 2 (IgG/IgM) were used as confirmatory assays to resolve discrepancies. The best concordance for VCA IgM detection was between Immulite and Vidas; for VCA IgG and EBNA-1 IgG were between Architect and Vidas. The sensitivities and specificities for VCA IgM were 97% and 88% for IFA, 100% and 94% for Architect, 100% and 99% for Vidas, and 100% and 100% for Immulite, respectively. The most problematic marker was EBNA-1 IgG with a 68.1% specificity by Immulite. Vidas panel had a perfect performance (100%) for determining all EBV profiles. Overall, evaluated assays had comparable performance. There were more discordant VCA IgG and EBNA-1 IgG results than VCA IgM results. The agreement between Architect and Vidas was better than other assays.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/imunologia , Kit de Reagentes para Diagnóstico/normas , Testes Sorológicos/normas , Adolescente , Adulto , Antígenos Virais/imunologia , Proteínas do Capsídeo/imunologia , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Humanos , Imunoglobulina M/sangue , Lactente , Medições Luminescentes/instrumentação , Medições Luminescentes/normas , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Testes Sorológicos/instrumentação , Testes Sorológicos/métodos , Adulto Jovem
10.
PLoS One ; 16(7): e0253807, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34242264

RESUMO

Determining values of plasma renin activity (PRA) or plasma active renin concentration (ARC), plasma aldosterone concentration (PAC), and aldosterone-to-renin ratio (ARR) is essential to diagnose primary aldosteronism (PA), but it takes several days with conventional radioimmunoassays (RIAs). Chemiluminescent enzyme immunoassays for PAC and ARC using the Accuraseed® immunoanalyzer facilitated the determination, but relations between Accuraseed® immunoanalyzer-based and RIA-based values in samples of PA confirmatory tests and adrenal venous sampling remained to be elucidated. We addressed this issue in the present study. This is a prospective, cross-sectional study. ARC and PAC values were measured by the Accuraseed® immunoanalyzer in samples, in which PRA and PAC values had been measured by the PRA-FR® RIA and SPAC®-S Aldosterone kits, respectively. The relations between Accuraseed® immunoanalyzer-based and RIA-based values were investigated with regression analyses. The optimal cutoff of Accuraseed® immunoanalyzer-based ARR for PA screening was determined by the receiver operating characteristic analysis. After log-log transformations, linear relations with high coefficients of determination were observed between Accuraseed® immunoanalyzer-based and RIA-based data of renin and aldosterone. Following the PA guidelines of Japan Endocrine Society, Accuraseed® immunoanalyzer-based cutoffs were calculated from the regression equations: the basal PAC for PA screening >12 ng/dL, PAC for the saline infusion test >8.2 ng/dL, ARC for the furosemide-upright test <15 pg/mL, and ARR for the captopril challenge test >3.09 ng/dL per pg/mL. The optimal cutoff of Accuraseed® immunoanalyzer-based ARR for PA screening was >2.43 ng/dL over pg/mL not to overlook bilateral PA patients. The present study provided conversion formulas between Accuraseed® immunoanalyzer-based and RIA-based values of renin, aldosterone, and ARR, not only in basal samples but also in samples of PA confirmatory tests and adrenal venous sampling. Although validation studies are awaited, the present study will become priming water of harmonization of renin and aldosterone immunoassays.


Assuntos
Aldosterona/sangue , Hiperaldosteronismo/diagnóstico , Programas de Rastreamento/instrumentação , Renina/sangue , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Hiperaldosteronismo/sangue , Japão , Medições Luminescentes/instrumentação , Medições Luminescentes/normas , Medições Luminescentes/estatística & dados numéricos , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Radioimunoensaio/instrumentação , Radioimunoensaio/normas , Radioimunoensaio/estatística & dados numéricos , Valores de Referência
11.
Int J Lab Hematol ; 43(6): 1593-1598, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34252265

RESUMO

BACKGROUND: The Sysmex CN-6500 is a new haemostasis analyser with an integrated immunoassay module that performs chemiluminescence enzyme assay (CLEIA) in addition to coagulation, turbidimetric, chromogenic and platelet aggregation tests. AIMS: To evaluate the analytical performance of the CN-6500 against the predicate device (Sysmex HISCL-800) for soluble thrombomodulin (TM), thrombin-antithrombin (TAT), tissue plasminogen activator/plasminogen activator inhibitor 1 complex (tPAI-C) and plasmin α2 plasmin inhibitor complex (PIC) assays. METHODS: Imprecision was assessed by testing two levels of quality control plasmas 10 times on 5 separate days. Comparability was studied in 230 plasmas from normal donors (n = 30), patients with suspected disseminated intravascular coagulation (DIC, n = 100), sepsis (n = 20) or liver disease (n = 20), lipaemic (n = 20), haemolysed (n = 20) and icteric samples (n = 20). Limit of detection, limit of quantitation and linearity were determined by testing serial dilutions of normal plasma. Sample carryover was assessed by testing samples with high and low normal levels of the analytes concerned. RESULTS: The CN-6500 performed 21 CLEIA tests per hour, while simultaneously performing coagulation tests. Acceptable between-run imprecision was obtained using commercial controls with normal and high activity for each analyte (%CV <4%), for all four assays. Excellent linearity was observed (slope 0.89-1.03; r2 >0.99) across the measurement range. The lower limits of detection and quantitation were as follows: TM <0.3/0.6 TU/ml, TAT >0.1/<0.2 ng/ml, PIC <0.004/<0.008 µg/ml and tPAI-C < 0.01/<0.1 ng/ml, respectively. All four assays showed excellent correlation between analysers and were unaffected by haemolysis, icterus or lipaemia. No carryover was observed. CONCLUSIONS: Our data demonstrate that the performance of the CLEIA assays on the CN-6500 is comparable to that of a stand-alone immunoassay analyser.


Assuntos
Testes de Coagulação Sanguínea/normas , Técnicas Imunoenzimáticas/métodos , Técnicas Imunoenzimáticas/normas , Medições Luminescentes/métodos , Medições Luminescentes/normas , Automação Laboratorial , Coagulação Sanguínea , Testes de Coagulação Sanguínea/instrumentação , Testes de Coagulação Sanguínea/métodos , Humanos , Técnicas Imunoenzimáticas/instrumentação , Medições Luminescentes/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
STAR Protoc ; 2(3): 100664, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34308379

RESUMO

Luminescent solar concentrators (LSCs) are simple and cost-effective solar energy-harvesting devices. Indium phosphide (InP)-based colloidal quantum dots (QDs) are promising QDs for efficient LSC devices due to their environmentally benign nature. One major challenge in LSC devices is reabsorption losses. To minimize the reabsorption, Stokes shift engineering is a critical process to designing the QD material. Here, we present a protocol that contains the preparation of structurally engineered copper-doped InP/ZnSe QDs and their LSC application. For complete details on the use and execution of this protocol, please refer to Sadeghi et al. (2020).


Assuntos
Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Pontos Quânticos/química , Cobre/química , Desenho de Equipamento , Índio/química , Luminescência , Fosfinas/química , Compostos de Selênio/química , Energia Solar , Espectrofotometria Ultravioleta , Compostos de Zinco/química
13.
Food Chem ; 362: 130219, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34091170

RESUMO

The use of artificial colorants in food is highly regulated due to their potential to harm human health. Thus, it is crucial to detect these substances effectively to ensure conformance with industrial standards. In this work, we prepared a photomultiplier tube (PMT)-based electrochemiluminescence (ECL) sensor and a charged coupled device (CCD)-based ECL sensor and compared their merits in the detection of sunset yellow (SY) dye. The sensors used C,N quantum dot-embedded g-C3N4 nanosheets (QDs@NSs) as the ECL agent and K2S2O8 as the coreactant. SY was analyzed on the basis of amplification in the QDs@NHs-K2S2O8 ECL system. The PMT-based sensor realized ultrasensitive detection using a single electrode, especially at low concentrations of SY. A CCD-based sensor imaged the ECL phenomenon of an electrode array and provided the advantages of high throughput and time savings. Under optimized conditions, both sensors exhibited high specificity, reproducibility and stability; detection limits of 20 nM with PMT detection and 5 µM with CCD detection were determined for SY, with detection ranging over at least two decades. The practical feasibilities of these systems were confirmed by satisfactory detection of SY in real drink samples.


Assuntos
Compostos Azo/análise , Bebidas Gaseificadas/análise , Técnicas Eletroquímicas/instrumentação , Corantes de Alimentos/análise , Compostos Azo/química , Técnicas Eletroquímicas/métodos , Eletrodos , Corantes de Alimentos/química , Limite de Detecção , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Nanoestruturas , Pontos Quânticos , Reprodutibilidade dos Testes
14.
Methods Mol Biol ; 2277: 175-185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34080152

RESUMO

The Protoporphyrin IX-Triplet State Lifetime Technique (PpIX-TSLT) has been proposed by us as a potential clinical noninvasive tool for monitoring mitochondrial function. We have been working on the development of mitochondrial respirometry for monitoring mitochondrial oxygen tension (mitoPO2) and mitochondrial oxygen consumption (mitoVO2) in skin. In this work, we describe the principles of the method in small experimental animals.


Assuntos
Mitocôndrias/metabolismo , Consumo de Oxigênio , Ácido Aminolevulínico/farmacologia , Animais , Temperatura Corporal , Desenho de Equipamento , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Protoporfirinas/química , Ratos Wistar , Respiração Artificial , Pele/efeitos dos fármacos , Traqueotomia
15.
Anal Bioanal Chem ; 413(17): 4493-4500, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34041573

RESUMO

Pepsinogen I (PGI) can reflect the morphology and function of the gastric mucosa. Accordingly, the large-scale community health screening of PGI can dramatically increase the early diagnosis rate of gastric cancer. However, PGI testing can only be carried out in comprehensive hospitals and health examination centers. To ameliorate this issue, a point-of-care chemiluminescent immunoassay for PGI was developed in a fully automated miniaturized instrument. This instrument was especially developed for health check-ups in the grassroots communities; its volume of which is only 0.18 m3. Critically, the entire detection process for a single sample only requires 20 min, and the samples can be loaded continuously, making the method suitable for high-throughput analysis. The assay displayed an excellent detection limit of 0.048 ng/mL with a broad detection range of 0-200 ng/mL. Furthermore, this assay exhibited high sensitivity and specificity, had low intra- and inter-assay coefficients of variation (<10%), and was not affected after storage at 37 °C for 7 days. The assay was used to detect PGI in 95 clinical serum samples, and the results were highly correlated with those that were clinically tested (correlation coefficient, R2 = 0.998). Hence, the method established in this work has great application value and can be broadly applied for the large-scale screening of gastric cancer in resource-limited areas.


Assuntos
Detecção Precoce de Câncer/instrumentação , Medições Luminescentes/instrumentação , Pepsinogênio A/sangue , Testes Imediatos , Neoplasias Gástricas/sangue , Humanos , Imunoensaio/instrumentação , Limite de Detecção , Neoplasias Gástricas/diagnóstico
16.
Nat Commun ; 12(1): 2680, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976191

RESUMO

Bioluminescent imaging (BLI) is one of the most powerful and widely used preclinical imaging modalities. However, the current technology relies on the use of transgenic luciferase-expressing cells and animals and therefore can only be applied to a limited number of existing animal models of human disease. Here, we report the development of a "portable bioluminescent" (PBL) technology that overcomes most of the major limitations of traditional BLI. We demonstrate that the PBL method is capable of noninvasive measuring the activity of both extracellular (e.g., dipeptidyl peptidase 4) and intracellular (e.g., cytochrome P450) enzymes in vivo in non-luciferase-expressing mice. Moreover, we successfully utilize PBL technology in dogs and human cadaver, paving the way for the translation of functional BLI to the noninvasive quantification of biological processes in large animals. The PBL methodology can be easily adapted for the noninvasive monitoring of a plethora of diseases across multiple species.


Assuntos
Fenômenos Biológicos , Diagnóstico por Imagem/métodos , Medições Luminescentes/métodos , Modelos Animais , Animais , Animais Geneticamente Modificados , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/metabolismo , Cães , Luciferina de Vaga-Lumes/química , Luciferina de Vaga-Lumes/metabolismo , Humanos , Luciferases/química , Luciferases/genética , Luciferases/metabolismo , Medições Luminescentes/instrumentação , Estrutura Molecular , Reprodutibilidade dos Testes
17.
Opt Lett ; 46(10): 2517-2520, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33988624

RESUMO

Microsphere biolasers have attracted a great deal of interest due to their potential for biosensing and cell tracking. Here we demonstrate a novel, to the best of our knowledge, microfluidic-based fabrication of nearly monodisperse dye-doped protein microsphere biolasers with a tunable size from 150 to 50 µm. In particular, for an 85 µm-bead, about 70% of the fabricated microspheres have the same size of 85 µm. Under optical pumping, the fabricated microspheres emit whispering gallery mode lasing emission with a lasing threshold of ${{7}}\;\unicode{x00B5} {\rm{J}}\;{{\rm{mm}}^{- 2}}$ and quality ($\!Q$) factor up to 3000. Interestingly, microspheres with the same size exhibit a similar lasing threshold and spectrum. The result indicates a high reproducibility of microsphere biolasers by the microfluidic-based fabrication technique. This Letter provides an effective method for mass production of high-$Q$ factor microsphere biolasers which is a significant step toward real biosensing and medical applications.


Assuntos
Técnicas Biossensoriais/instrumentação , Lasers , Medições Luminescentes/instrumentação , Microesferas
18.
Scand J Clin Lab Invest ; 81(4): 332-338, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33798031

RESUMO

Transition to new analytical systems and methods requires end-user verification to ensure acceptability for routine use. Our aim was to verify precision of MAGLUMI 800 immunoassay analyzer for 17-hydroxyprogesterone (17-OHP), 25-hydroxy vitamin D (25(OH)D), aldosterone, androstenedione, growth hormone (GH), insulin-like growth factor 1 (IGF-1), insulin-like growth factor-binding protein 3 (IGFBP-3) and renin, as well as to assess their comparability with the routinely used assays. Precision was evaluated at two levels following the CLSI EP15-A2 protocol. Method comparison included parallel analysis of 40 routine samples for each assay on MAGLUMI 800 and the routinely used automated or manual immunoassays. Within-run coefficients of variation (CV) ranged from 0.8% (androstenedione) to 14.5% (aldosterone), between-run CVs from 1.0% (IGFBP-3) to 12.8% (renin), while within-laboratory (total) precision CVs were from 2.1% (IGFBP-3) to 14.9% (renin). All assays with the exception of IGF-1 and 25(OH)D at the low concentration control level, satisfied biological variation criteria for imprecision. Passing-Bablok regression showed proportional difference for 17-OHP and aldosterone, constant for androstenedione, while both constant and proportional difference was revealed for 25(OH)D, GH and IGF-1. Statistically significant relative biases higher than the desirable biological variation acceptance criteria were observed for 17-OHP, 25(OH)D, aldosterone, androstenedione and IGF-1. The evaluated assays need further assessment as well as verification of reference intervals in order to be suitable for introduction into routine practice in our laboratory. Our study clearly demonstrates that we are still far from achieving immunoassay standardization and comparability of results.


Assuntos
Técnicas de Diagnóstico Endócrino/instrumentação , Imunoensaio/instrumentação , 17-alfa-Hidroxiprogesterona/sangue , Aldosterona/sangue , Androstenodiona/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Imunoensaio/métodos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Vitamina D/análogos & derivados , Vitamina D/sangue
19.
Int J Legal Med ; 135(4): 1661-1668, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33783602

RESUMO

Forensic diagnosis of anaphylactic shock is a challenging task in forensic practice due to the lack of characteristic morphological changes. Postmortem analysis of serum IgE can provide helpful information for determining anaphylaxis. However, postmortem serum always suffers from hemolysis. To investigate the interference of hemolysis on postmortem analysis of total IgE by electrochemiluminescent immunoassay (ECLIA) and verify the suitability of the commercially available ECLIA kit for postmortem hemolyzed blood with the dilution-correction method, different levels of hemolyzed serum were prepared to evaluate the interference of hemolysis. A linear regression analysis was then performed on the concentration of total IgE in the completely hemolyzed blood and the corresponding serum. Our results indicated that hemolysis negatively interfered with the total IgE analysis by ECLIA and the interference (|Bias%|) increased with increasing levels of hemolysis. After controlling for |Bias%| by dilution, the test concentration of total IgE in the completely hemolyzed blood was still significantly lower than that in the serum (P < 0.05) and resulted in eight false-negative cases. A strong correlation was observed between the test concentration of total IgE in the completely hemolyzed blood and that in the serum (r = 0.983). After correction by the regression formula, the corrected concentration revealed no significant differences and exhibited the same diagnostic ability, compared with the serum total IgE concentration. These results indicate that the completely hemolyzed blood is not recommended for postmortem analysis of total IgE directly. The dilution-correction method might have potential utility in forensic practice for evaluating serum total IgE concentrations.


Assuntos
Hemólise , Imunoglobulina E/sangue , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Anafilaxia/sangue , Autopsia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Projetos Piloto
20.
Anal Bioanal Chem ; 413(16): 4119-4135, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33715042

RESUMO

Electrochemiluminescence (ECL) can be produced through two main routes: annihilation route and coreactant route. The vast majority of applications of ECL are based on coreactant ECL which can be generated in aqueous media at relatively low potentials compared with organic solvents. However, the development of more efficient ECL systems remains a compelling goal. Co-reaction accelerator (CRA) can significantly enhance the ECL signal through promoting more production of the coreactant intermediate. Compared with other ECL enhancement strategies, the CRA protocol is distinctive owing to its diverse, simple, and highly effective features. Various species such as inorganic compound, organic compound, and nanomaterials (NMs) have been developed as CRA and NM CRA has gained particular attention owing to their unique properties of excellent catalytic behavior and large surface area. By integration with the inherent advantages of ECL, bioanalysis based on CRA-enhanced ECL showed excellent performance such as ultrahigh sensitivity, wide dynamic range, low cost, simple instrumentation, and measurements in complex media. It has been extensively applied in various fields including clinical diagnosis, environmental monitoring, and food safety. Therefore, it is of great interest to present a systematic and critical review on the advances in ECL CRA. Herein, the recent progress on CRA and its applications in ECL bioanalysis are summarized by illustrating some representative work and a discussion of the future development trends of CRA ECL is offered.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Medições Luminescentes/métodos , Animais , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Humanos , Medições Luminescentes/instrumentação , Metais Pesados/análise , MicroRNAs/análise , Nanoestruturas/química , Proteínas/análise
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