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1.
Curr Microbiol ; 81(9): 291, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39088066

RESUMEN

A novel Gram-stain-positive, aerobic, catalase-positive, oxidase-negative, non-motile, and rod-shaped bacterium with ibuprofen-degrading capacity, designated DM4T, was isolated from the sewage of a wastewater treatment plant (WWTP) in Guangzhou city, China. Strain DM4T grew optimally at 0% (w/v) NaCl, pH 5.0-7.0, and 30 °C, forming white colonies on trypticase soy agar. C18:1ω9c, C18:2ω9.12c and C15:1ω10c were the predominant fatty acids. Results of 16S rRNA gene alignment and phylogenetic analysis indicated that strain DM4T belonged to the genus Patulibacter, was closely related to Patulibacter medicamentivorans DSM 25692T (98.5%) and P. brassicae KCTC 39817T (98.1%). Strain DM4T had a genome size of 5.33Mbp, and the DNA G + C content was 75.0%. The average nucleotide identity (ANI), average amino acid identity (AAI), and digital DNA-DNA hybridisation (dDDH) values between strain DM4T and P. medicamentivorans were 85.2%, 83.9%, and 29.0% respectively, while those between strain DM4T and P. brassicae were 78.5%, 71.3%, and 22.2%, respectively. Strain DM4T could significantly degrade ibuprofen by almost 80% after 84 h of incubation, and the degradation kinetics was well fitted with the first-order kinetics. Evidence from phenotypic, phylogenetic and chemotaxonomic analyses support that strain DM4T (= GDMCC 1.4574T = KCTC 59145T) represents a new species of the genus Patulibacter, for which the name Patulibacter defluvii sp. nov. is proposed.


Asunto(s)
Composición de Base , ADN Bacteriano , Ácidos Grasos , Filogenia , ARN Ribosómico 16S , Aguas Residuales , China , Aguas Residuales/microbiología , ARN Ribosómico 16S/genética , Ácidos Grasos/análisis , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Aguas del Alcantarillado/microbiología , Análisis de Secuencia de ADN , Ibuprofeno
2.
Artículo en Inglés | MEDLINE | ID: mdl-39213055

RESUMEN

OBJECTIVES: To investigate the diagnostic value of CEUS combined with C-TIRADS for indeterminate FNA cytological thyroid nodules. METHODS: The clinical data, ultrasonic images, C-TIRADS categories and CEUS images of 192 patients with indeterminate FNA cytological thyroid nodules confirmed by the surgical pathology were analyzed retrospectively. The diagnostic efficacy of CEUS, C-TIRADS and CEUS-TIRADS were calculated. RESULTS: The AUCs of CEUS, C-TIRADS and CEUS-TIRADS were 0.905 (95% CI: 0.862∼0.949), 0.881 (95% CI: 0.825∼0.938) and 0.954 (95% CI: 0.922∼0.986), respectively. The sensitivity, specificity, PPV, NPV, accuracy, LR- and LR+ were 84.7% (116/137), 85.5% (47/55), 93.5% (116/124), 69.1% (47/68), 84.9% (163/192), 0.179, 5.82 and 84.7% (116/137), 83.6% (46/55), 92.8% (116/125), 68.7% (46/67), 84.4% (162/192), 0.183, 5.17, 92.7% (127/137), 89.1% (49/55), 95.5% (127/133), 83.1% (49/59), 91.7% (176/192), 0.082, and 8.50, respectively. Compared with CEUS and C-TIRADS, CEUS-TIRADS had improved the AUC, sensitivity and accuracy (all P < 0.05). CONCLUSIONS: CEUS and C-TIRADS had high diagnostic values in indeterminate FNA cytological thyroid nodules. CEUS-TIRADS improved AUC, diagnostic sensitivity and accuracy, and helped to distinguish indeterminate FNA cytological nodules.

3.
Microbiol Spectr ; 12(6): e0381123, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38647341

RESUMEN

In the nitrogen biogeochemical cycle, the reduction of nitrous oxide (N2O) to N2 by N2O reductase, which is encoded by nosZ gene, is the only biological pathway for N2O consumption. In this study, we successfully isolated a strain of denitrifying Paracoccus denitrificans R-1 from sewage treatment plant sludge. This strain has strong N2O reduction capability, and the average N2O reduction rate was 5.10 ± 0.11 × 10-9 µmol·h-1·cell-1 under anaerobic condition in a defined medium. This reduction was accompanied by the stoichiometric consumption of acetate over time when N2O served as the sole electron acceptor and the reduction can yield energy to support microbial growth, suggesting that microbial N2O reduction is related to the energy generation process. Genomic analysis showed that the gene cluster encoding N2O reductase of P. denitrificans R-1 was composed of nosR, nosZ, nosD, nosF, nosY, nosL, and nosZ, which was identified as that in other strains in clade I. Respiratory inhibitors test indicated that the pathway of electron transport for N2O reduction was different from that of the traditional electron transport chain for aerobic respiration. Cu2+, silver nanoparticles, O2, and acidic conditions can strongly inhibit the reduction, whereas NO3- or NH4+ can promote it. These findings suggest that modular N2O reduction of P. denitrificans R-1 is linked to the electron transport and energy conservation, and dissimilatory N2O reduction is a form of microbial anaerobic respiration. IMPORTANCE: Nitrous oxide (N2O) is a potent greenhouse gas and contributor to ozone layer destruction, and atmospheric N2O has increased steadily over the past century due to human activities. The release of N2O from fixed N is almost entirely controlled by microbial N2O reductase activities. Here, we investigated the ability to obtain energy for the growth of Paracoccus denitrificans R-1 by coupling the oxidation of various electron donors to N2O reduction. The modular N2O reduction process of denitrifying microorganism not only can consume N2O produced by itself but also can consume the external N2O generated from biological or abiotic pathways under suitable condition, which should be critical for controlling the release of N2O from ecosystems into the atmosphere.


Asunto(s)
Desnitrificación , Óxido Nitroso , Paracoccus denitrificans , Paracoccus denitrificans/metabolismo , Paracoccus denitrificans/genética , Paracoccus denitrificans/crecimiento & desarrollo , Óxido Nitroso/metabolismo , Transporte de Electrón , Oxidorreductasas/metabolismo , Oxidorreductasas/genética , Oxidación-Reducción , Aguas del Alcantarillado/microbiología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Electrones
4.
Bioelectrochemistry ; 157: 108677, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38430576

RESUMEN

Cathodic photoelectrochemical (PEC) analysis has received special concerns because of its outstanding anti-interference capability toward reductive substances in samples, so it is highly desirable to develop high-performance photocathodic materials for PEC analysis. Herein, a Zr-based metal-organic framework (Zr-MOF), MOF-525, is explored as a photoactive material in aqueous solution for the first time, which shows a narrow band-gap of 1.82 eV, excellent visible-light absorption, and high cathodic PEC activity. A sandwiched-type PEC immunosensor for detecting prostate-specific antigen (PSA) is fabricated by using MIL-101-NH2(Fe) label and MOF-525 photoactive material. MIL-101-NH2(Fe) as a typical Fe-MOF can serve as a peroxidase mimic to catalyze the production of precipitates on the photoelectrode. Both the produced precipitates and the MIL-101-NH2(Fe) labels can quench the photocathodic current, enabling "signal-off" immunosensing of PSA. The detection limit is 3 fg mL-1, and the linear range is between 10 fg mL-1 and 100 ng mL-1 for detecting PSA. The present study not only develops a high-performance Zr-MOF photoactive material for cathodic PEC analysis but also constructs a sensitive PEC immunosensing platform based on the dual-signal amplification of peroxidase-mimetic Fe-MOF.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Humanos , Masculino , Estructuras Metalorgánicas/química , Antígeno Prostático Específico/análisis , Peroxidasa , Técnicas Electroquímicas , Inmunoensayo , Límite de Detección
5.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(12): 1505-1513, 2023 Dec 15.
Artículo en Chino | MEDLINE | ID: mdl-38130195

RESUMEN

Objective: To develop a drug-loaded composite microsphere that can simultaneously release the berberine (BBR) and naringin (NG) to repair infectious bone defects. Methods: The NG was loaded on mesoporous microspheres (MBG) to obtain the drug-loaded microspheres (NG-MBG). Then the dual drug-loaded compound microspheres (NG-MBG@PDA-BBR) were obtained by wrapping NG-MBG with polydopamine (PDA) and modifying the coated PDA with BBR. The composite microspheres were characterized by scanning electron microscopy, X-ray diffraction, specific surface area and pore volume analyzer, and Fourier transform infrared spectroscopy; the drug loading rate and release of NG and BBR were measured; the colony number was counted and the bacterial inhibition rate was calculated after co-culture with Staphylococcus aureus and Escherichia coli for 12 hours to observe the antibacterial effect; the biocompatibility was evaluated by live/dead cell fluorescence staining and cell counting kit 8 assay after co-culture with rat's BMSCs for 24 and 72 hours, respectively, and the osteogenic property was evaluated by alkaline phosphatase (ALP) staining and alizarin red staining after 7 and 14 days, respectively. Results: NG-MBG@PDA-BBR and three control microspheres (MBG, MBG@PDA, and NG-MBG@PDA) were successfully constructed. Scanning electron microscopy showed that NG-MBG@PDA-BBR had a rough lamellar structure, while MBG had a smooth surface, and MBG@PDA and NG-MBG@PDA had a wrapped agglomeration structure. Specific surface area analysis showed that MBG had a mesoporous structure and had drug-loading potential. Low angle X-ray diffraction showed that NG was successfully loaded on MBG. The X-ray diffraction pattern contrast showed that all groups of microspheres were amorphous. Fourier transform infrared spectroscopy showed that NG and BBR peaks existed in NG-MBG@PDA-BBR. NG-MBG@PDA-BBR had good sustained drug release ability, and NG and BBR had early burst release and late sustained release. NG-MBG@PDA-BBR could inhibit the growth of Staphylococcus aureus and Escherichia coli, and the antibacterial ability was significantly higher than that of MBG, MBG@PDA, and NG-MBG@PDA ( P<0.05). But there was a significant difference in biocompatibility at 72 hours among microspheres ( P<0.05). ALP and alizarin red staining showed that the ALP positive area and the number of calcium nodules in NG-MBG@PDA-BBR were significantly higher than those of MBG and NG-MBG ( P<0.05), and there was no significant difference between NG-MBG@PDA and NG-MBG@PDA ( P>0.05). Conclusion: NG-MBG@PDA-BBR have sustained release effects on NG and BBR, indicating that it has ideal dual performance of osteogenesis and antibacterial property.


Asunto(s)
Berberina , Osteogénesis , Ratas , Animales , Preparaciones de Acción Retardada/farmacología , Microesferas , Berberina/farmacología , Antibacterianos/farmacología , Escherichia coli
6.
Anal Chem ; 95(45): 16754-16760, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37919241

RESUMEN

Photocurrent polarity switchable photoelectrochemical (PEC) sensing has superior accuracy and anti-interference ability to conventional PEC sensing. The development of a novel strategy for photocurrent polarity switchable sensing is of great interest. Herein, a novel strategy for photocurrent polarity switchable sensing is reported by regulating electrostatic interactions between two semiconductor photoactive materials. Hyaluronic acid (HA)-modified CuO nanosheets show a negatively charged surface, which prevents the attachment of CuO nanosheets to negatively charged CdS nanodendrite-modified photoelectrodes because of the strong electrostatic repulsion. In the presence of hyaluronidase (HAase), the specific hydrolysis of HA on the surface of CuO by HAase can yield a positively charged surface, so CuO can be attached to a CdS-modified photoelectrode via electrostatic attraction, leading to photocurrent polarity switching. The photocurrent polarity switchable detection of HAase activity is achieved with an ultralow detection limit of 2 × 10-3 U mL-1 and a wide linear detection range between 0.01 and 100 U mL-1. This work provides a new and effective photocurrent polarity switching strategy for PEC sensing and a simple and efficient method for detecting HAase activity.

7.
Biosens Bioelectron ; 219: 114813, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36270081

RESUMEN

It is important to develop effective strategies to construct enzymatic biofuel cell based self-powered biosensors. We report here the facile regulation of enzymatic loading capacity on the bioanode by utilizing a concatenated catalytic hairpin assembly (CHA)/hybridization chain reaction (HCR) and its application for self-powered microRNA-141 (miRNA-141) detection. To construct the bioanode, a concatenated CHA/HCR process triggered by miRNA-141 was conducted on the three-dimensional macroporous gold (3DMG) electrode to generate long double-stranded DNA nanowires for glucose oxidase immobilization. Quartz crystal microbalance study reveals that the enzymatic loading capacity on the bioanode increases at an increasing miRNA-141 concentration, leading to enhanced catalytic performance for glucose oxidation. The short-circuit currents of the assembled glucose/O2 biofuel cells increase at increasing miRNA-141 concentrations, enabling ultrasensitive detection of miRNA-141. The self-powered biosensor features a wide dynamic range for detecting miRNA-141 from 10-17 to 10-11 M, with an ultralow detection limit of 1.3 aM. This work provides a highly sensitive self-powered biosensing platform for miRNA detection.

8.
Mar Pollut Bull ; 185(Pt B): 114351, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36401947

RESUMEN

Ammonia-oxidizing bacteria (AOB) catalyze the first step of nitrification, oxidizing ammonia to nitrite, and are characterized by amoA gene encoding ammonia monooxygenase. To analyze the AOB community effectively, an integral taxonomy database containing 14,058 amoA sequences and the optimal cut-off value at 95 % for OTU clustering were determined. This method was evaluated to be efficient by the analysis of environmental samples from the river, estuary, and sea. Using this method, a significant spatial variance of the AOB community was found. The diversity of AOB was highest in the estuary and lowest in the ocean. Nitrosomonas were the predominant AOB in the sediments of the freshwater river and estuary. Nearly all the AOB-amoA sequences belonged to uncultured bacterium in the sediments of deep sea. In general, an integral AOB taxonomic database and a suitable cut-off value were constructed for the comprehensive exploration of the diversity of AOB from river to sea.


Asunto(s)
Betaproteobacteria , Ríos , Amoníaco , Genes Bacterianos , Oxidación-Reducción
9.
Analyst ; 147(24): 5747-5753, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36413105

RESUMEN

Photosensitizers and enzyme mimics are extensively used in photoelectrochemical (PEC) sensing, but few materials can be used as both photosensitizers and enzyme mimics in PEC sensing. Herein, we report Au nanoclusters (AuNCs) as both photosensitizers and peroxidase mimics for sensitive PEC sensing of Hg2+. It is found that AuNCs can act as photosensitizers to improve the PEC activity of WO3 nanorods; so the WO3/AuNCs composite material can be used as an advanced photosensitive material for PEC detection. AuNCs can also catalyze precipitate formation on the photoelectrode because of their peroxidase mimetic activity, and the interface electron transfer is hindered by the formed precipitate. Thus, the photocurrent of the WO3/AuNCs-based photoelectrode is quenched. When Hg2+ is present, the AuNCs-catalyzed precipitate formation is inhibited by Hg2+ because of the binding of Hg2+ to AuNCs through Hg2+-Au+ interactions. The photocurrent of the WO3/AuNCs-based photoelectrode increases accordingly, enabling "signal on" PEC detection of Hg2+. A broad linear range for Hg2+ detection is achieved between 1.0 pM and 50 nM with a detection limit of 0.2 pM. We have developed an advanced photosensitive material and introduced a simple method for PEC detection of Hg2+.


Asunto(s)
Mercurio , Nanotubos , Fármacos Fotosensibilizantes , Catálisis , Peroxidasas
10.
Anal Chem ; 94(40): 13913-13920, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36166257

RESUMEN

A signaling strategy can directly determine the analytical performance and application scope of photoelectrochemical (PEC) immunoassays, so it is of great significance to develop an effective signaling strategy. The electro-Fenton reaction has been extensively used to degrade organic pollutants, but it has not been applied to PEC immunoassays. Herein, we report a novel signaling strategy for a PEC immunoassay based on electro-Fenton degradation of liposomes (Lip) on a photoelectrode. Lip vesicles are coated on Au@TiO2 core-shell photoactive material, which can prevent ascorbic acid (AA) from scavenging photogenerated holes. In the presence of a target, the immunomagnetic bead labels are converted to Fe3+ for electro-Fenton reaction, and hydroxyl radicals generated by the electro-Fenton reaction can degrade the Lip vesicles on the photoelectrode. Because of the degradation of Lip vesicles, photogenerated holes can be scavenged more effectively by AA, leading to an increase in photocurrent. Based on the electro-Fenton-regulated interface electron transfer, the sensitive "signal on" PEC immunoassay of a carcinoembryonic antigen is achieved, which features a dynamic range from 0.05 to 5 × 104 pg mL-1 and a detection limit of 0.01 pg mL-1. Our work provides a novel and efficient PEC immunoassay platform by introducing the electro-Fenton reaction into PEC analysis.


Asunto(s)
Técnicas Biosensibles , Contaminantes Ambientales , Ácido Ascórbico , Antígeno Carcinoembrionario/análisis , Técnicas Electroquímicas , Contaminantes Ambientales/análisis , Inmunoensayo , Límite de Detección , Liposomas , Polímeros
11.
Talanta ; 249: 123660, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35689947

RESUMEN

We report here Au nanoparticles (AuNPs)/SnS2/ZnIn2S4 as a high-performance active material for sensitive photoelectrochemical (PEC) determination of T4 polynucleotide kinase (T4 PNK) using an enzymatic reaction-induced DNA structure switch strategy. To construct the PEC biosensor, a double-stranded DNA probe consisting of a CdS quantum dots (QDs)-labeled single-stranded DNA (sDNA) and its complementary DNA (cDNA) is immobilized on the AuNPs/SnS2/ZnIn2S4 photoactive material. T4 PNK can catalyze the phosphorylation of 5'-OH-terminated sDNA in the double-stranded DNA probe when ATP is present, and λ-exonuclease can catalyze the degradation of the phosphorylated sDNA into small fragments. Then the cDNA forms a hairpin structure so that CdS QDs and AuNPs are in close contact, which can induce exciton-plasma interactions between CdS QDs and AuNPs. The exciton-plasma interactions significantly boost the photocurrent, enabling the "signal on" PEC determination of T4 PNK in the range of 10-4 - 1 U mL-1 with a detection limit of 6 × 10-5 U mL-1. The PEC biosensor can also be used to screen enzyme inhibitors.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Puntos Cuánticos , ADN/química , ADN Complementario , Oro/química , Límite de Detección , Nanopartículas del Metal/química , Polinucleótido 5'-Hidroxil-Quinasa
12.
Chem Commun (Camb) ; 58(57): 7960-7963, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35758059

RESUMEN

CdS quantum dots (QDs) are attached onto zirconium-based metal-organic frameworks (Zr-MOFs) with DNA as a bridge to boost the photoelectrochemical (PEC) activity of Zr-MOFs, and the sensitization of Zr-MOFs by using CdS QDs is regulated by the alkaline phosphatase (ALP)-catalyzed hydrolysis of tripolyphosphate, enabling sensitive "signal-on" PEC detection of ALP activity.


Asunto(s)
Técnicas Biosensibles , Compuestos de Cadmio , Estructuras Metalorgánicas , Puntos Cuánticos , Fosfatasa Alcalina , Límite de Detección
13.
Chem Commun (Camb) ; 58(17): 2922-2925, 2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35142303

RESUMEN

With the aid of an exonuclease-powered DNA walker, the amount of glucose oxidase immobilized on the bioanode can be facilely tailored by varying the concentration of microRNA-141, so a glucose/O2 biofuel cell is employed as a self-powered sensor for sensitive and selective detection of microRNA-141.


Asunto(s)
Fuentes de Energía Bioeléctrica , ADN/química , Glucosa/química , MicroARNs/análisis , Oxígeno/química
14.
Clin Hemorheol Microcirc ; 81(1): 13-21, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35068450

RESUMEN

OBJECTIVES: To compare the diagnostic value of shear wave elastography (SWE), fine needle aspiration (FNA) and BRAF gene detection (BRAFV600E gene mutation detection) in ACR TI-RADS 4 and 5 thyroid nodules. METHODS: SWE images, FNA cytological results and BRAF detection results of ACR TI-RADS 4 and 5 thyroid nodules confirmed by pathology were analyzed retrospectively. The receiver operating characteristic (ROC) curve was drawn to determine the best cutoff value of SWE Emax. In the combined diagnosis of SWE, FNA and BRAF, firstly, the nodules with BRAF gene mutation were included in the positive ones, secondly, the nodules with benign and malignant FNA were included in the FNA + SWE or FNA + SWE + BRAF negative and positive ones respectively, finally, for FNA uncertain nodules: those whose SWE Emax were less than or equal to the cutoff value were included in FNA + SWE or FNA + SWE + BRAF negative ones, and those whose SWE Emax were greater than the cutoff value were included in positive ones. The diagnostic efficacy of SWE, FNA, SWE + FNA, FNA + BRAF and their combination in ACR TI-RADS 4 and 5 thyroid nodules were compared. RESULTS: The ROC curve showed that the best cutoff value of SWE Emax was 40.9 kpa, and the area under ROC curve (AUC) was 0.842 (0.800∼0.885). The sensitivity, specificity and accuracy of SWE were 76.3% (270/354), 75.5% (80/106) and 76.1% (350/460), respectively. The sensitivity, specificity and accuracy of FNA were 58.2% (206/354), 88.7% (94/106) and 65.2(300/460), respectively. The sensitivity, specificity and accuracy of FNA + BRAF were 95.5% (338/354), 88.7% (94/106) and 93.9% (432/460), respectively. The sensitivity, specificity and accuracy of SWE + FNA were 85.9% (304/354), 98.1% (104/106) and 88.7% (408/460), respectively. The sensitivity, specificity and accuracy of SWE + FNA + BRAF were 98.3% (348/354), 98.1% (104/106) and 98.3% (452/460), respectively. For the diagnostic accuracy, SWE + FNA + BRAF > FNA + BRAF > FNA + SWE > SWE > FNA, the difference was statistically significant (all P > 0.05). CONCLUSIONS: For ACR TI-RADS 4 and 5 thyroid nodules, SWE and FNA have high diagnostic efficiency. For the diagnostic accuracy, FNA + BRAF is better than FNA + SWE. FNA combination with BRAF gene detection further improves the diagnostic sensitivity and accuracy of FNA. The combined application of the three is the best.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Nódulo Tiroideo , Biopsia con Aguja Fina/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Humanos , Proteínas Proto-Oncogénicas B-raf/genética , Estudios Retrospectivos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/genética , Ultrasonografía/métodos
15.
Anal Chem ; 93(41): 13783-13790, 2021 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-34606246

RESUMEN

The development of efficient signaling strategies is highly important for photoelectrochemical (PEC) immunoassay. We report here a new and efficient strategy for sensitive PEC immunoassay by tailoring the electrostatic interaction between the photoactive material and the electron donor. The photoelectric conversion of hexametaphosphate (HMP)-capped CdS quantum dots (QDs) in Na2SO3 solution is significantly boosted after Ca2+ incubation. The negative surface charges on CdS@HMP QDs decrease because of the complexation reaction between HMP and Ca2+, and the electrostatic repulsion between CdS@HMP QDs and electron donor (SO32-) becomes weak accordingly, leading to an improved electron-hole separation efficiency. Inspired by the PEC response of CdS@HMP QDs to Ca2+, a novel "signal-on" PEC immunoassay platform is established by employing CaCO3 nanoparticles as labels. By regulating the surface charge of CdS@HMP QDs with in situ-generated Ca2+ from CaCO3 labels, sensitive detection of the carcinoembryonic antigen (CEA) is achieved. The linear detection range is 0.005-50 ng mL-1 and the detection limit is 1 pg mL-1 for CEA detection. Our work not only provides a facile route to tailor the photoelectric conversion but also lays the foundation for sensitive PEC immunoassay by simply regulating the surface charge of photoactive materials.


Asunto(s)
Técnicas Biosensibles , Compuestos de Cadmio , Puntos Cuánticos , Técnicas Electroquímicas , Inmunoensayo , Límite de Detección , Fosfatos , Sulfuros
16.
Chem Commun (Camb) ; 57(83): 10903-10906, 2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34590104

RESUMEN

We report here a novel photocurrent polarity switching strategy for a photoelectrochemical immunoassay driven by the covalent reaction between fullerenol (COH) and chloranilic acid (CA). The sensitive detection of interleukin-6 is achieved by using CA-encapsulated liposome as the label and COH-coated ZnO as the photoactive material, with a detection limit of 1.0 fg mL-1.


Asunto(s)
Fulerenos/química , Interleucina-6/sangre , Nanotubos/química , Óxido de Zinc/química , Anticuerpos/inmunología , Benzoquinonas/química , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Fulerenos/efectos de la radiación , Humanos , Inmunoensayo/métodos , Interleucina-6/inmunología , Límite de Detección , Liposomas/química , Nanotubos/efectos de la radiación , Procesos Fotoquímicos , Compuestos de Estaño/química , Óxido de Zinc/efectos de la radiación
17.
Talanta ; 233: 122521, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34215136

RESUMEN

Great efforts have been made to search for highly active catalysts toward electrochemical water splitting, but double-signal immunosensors have not been reported based on bifunctional water splitting electrocatalysts. We report here a dual-signal electrochemical immunosensor for detecting carcinoembryonic antigen (CEA) using multi-wall carbon nanotubes (MWCNTs)-cobalt phosphide (CoP) as an electrocatalytic label. The preparation of MWCNTs-CoP involves the growth of Co3O4 nanoparticles on MWCNTs and low-temperature phosphatization of Co3O4 nanoparticles. The MWCNTs-CoP catalyst shows excellent electrocatalytic activities in a neutral medium toward both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), enabling MWCNTs-CoP as the electrocatalytic label for sensitive immunosensing. The linear range of the sandwich-type immunosensor for detecting CEA based on the HER signal is from 10-4-100 ng mL-1, whereas a linear range for detecting CEA based on the OER signal is achieved from 10-4 to 10 ng mL-1. The detection limits for detecting CEA using HER and OER signals are 10 and 12 fg mL-1, respectively. This work can provide a new double-signal immunosensing platform based on a bifunctional water splitting electrocatalyst.


Asunto(s)
Técnicas Biosensibles , Nanotubos de Carbono , Antígeno Carcinoembrionario , Inmunoensayo , Fosfinas , Agua
18.
Clin Hemorheol Microcirc ; 78(2): 163-174, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33579829

RESUMEN

OBJECTIVE: To compare the diagnostic efficacy of ACR TI-RADS, Kwak TI-RADS, ATA guidelines and KTA/KSThR guidelines in combination with shear wave elastography (SWE) for thyroid nodules. METHODS: The retrospective study included 566 thyroid nodules with maximum diameter≥5 mm which confirmed by FNA cytology or/and surgical pathology. The sensitivity, specificity, accuracy, Youden index of diagnosis of thyroid nodules by ACR TI-RADS, Kwak TI-RADS, ATA guidelines, KTA/KSThR guidelines and SWE were calculated. The ROC curve was drawn to determine the cut-off values of the four ultrasound classification systems and SWE Emax. The diagnostic efficacy of the four ultrasound classification systems in combination with SWE were calculated and compared with those of pre-combination. RESULTS: The ROC curves indicated that the cut-off value of ACR TI-RADS, Kwak TI-RADS, ATA guidelines, KTA/KSThR guidelines and Emax of SWE was TR5, 4c, high-suspicion, high-suspicion, and 41.7 kPa, respectively, and the area under the ROC curve (AUC) was 0.907(0.879-0.934), 0904(0.876-0.932), 0.894(0.863-0.924), 0.888(0.856-0.919), 0.886(0.859-0.913), respectively. After combination with SWE, the the sensitivities of the four ultrasound classification systems for the diagnosis of nodules were improved, and the differences were statistically significant (all P≤0.001); the specificities were decreased, but the differences were not statistically significant (all P > 0.05); the accuracies were improved, but only the difference of ACR TI-RADS was statistically significant (x2 = 4.45, P = 0.035); the differences in the AUCs were not significant (all P > 0.05). CONCLUSIONS: The four ultrasound classification systems and SWE all had high performance in the diagnosis of thyroid nodules. The four classification systems in combination with SWE were all beneficial to the differential diagnosis of nodules, and ACR TI-RADS in combination with SWE was more effective, especially for TR3 and TR4 nodules.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Guías de Práctica Clínica como Asunto/normas , Nódulo Tiroideo/diagnóstico , Ultrasonografía/métodos , Adulto , Área Bajo la Curva , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Nódulo Tiroideo/clasificación , Nódulo Tiroideo/diagnóstico por imagen
19.
Anal Chem ; 92(24): 16267-16273, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33231425

RESUMEN

The development of highly active electrocatalytic labels is important for constructing sensitive electrochemical immunosensors. Great progress has been made in developing non-noble-metal nanocatalysts toward the oxygen evolution reaction (OER) in the past decade, but non-noble-metal OER nanocatalysts have not been explored as electrocatalytic labels for immunosensing. Herein, we report NiCoO2@CeO2 nanoboxes (NBs) as novel electrocatalytic labels for ultrasensitive immunosensing based on the excellent OER activity of NiCoO2@CeO2 NBs in a neutral solution. The synthesis of NiCoO2@CeO2 NBs involves Ni2+ exchange and heat treatment of ZIF-67 nanocubes to produce NiCoO2 NBs, followed by the growth of CeO2 nanoparticles on the surface of NiCoO2 NBs. The NiCoO2@CeO2 NBs offer superior OER activity to NiCoO2 NBs because of the synergetic effect between NiCoO2 NBs and CeO2 nanoparticles. The formation of ester-like bridging between CeO2 and the carboxylic groups of antibody enables direct immobilization of the antibody on the NiCoO2@CeO2 surface. A sandwich-type electrochemical immunosensor using NiCoO2@CeO2 NBs as electrocatalytic labels features a broad linear range for interleukin-6 detection from 2.5 × 10-5 to 10 ng mL-1, with a low detection limit of 7 fg mL-1. Our work lays the foundation for developing electrochemical immunosensors and aptasensors based on non-noble-metal OER electrocatalysts.


Asunto(s)
Cerio/química , Inmunoensayo/métodos , Interleucina-6/análisis , Límite de Detección , Nanoestructuras/química , Óxidos/química , Oxígeno/química , Cobalto/química , Electroquímica , Interleucina-6/química , Níquel/química
20.
ACS Appl Mater Interfaces ; 12(26): 29066-29073, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32510918

RESUMEN

We report here CdS quantum-dots (QDs)-decorated V2O5 nanosheets as high-performance and chemically etchable photoelectric active materials for constructing a photoelectrochemical (PEC) immunoassay platform. CdS QDs-decorated V2O5 nanosheets as new photoelectric materials can show superior photocurrent to V2O5 nanosheets and CdS QDs under visible-light irradiation because of the promoted photogenerated electron-hole separation and the increased visible-light absorption. V2O5 nanosheets can be etched by ascorbic acid (AA) because of the reduction of V2O5 to V4+, and the photocurrent of CdS/V2O5-nanocomposite-modified indium tin oxide electrode decreases significantly after being etched by AA. Inspired by this phenomenon, a PEC immunoassay platform is constructed for carcinoembryonic antigen (CEA) detection by using CdS/V2O5 nanocomposite as the photoelectric material and AA-encapsulated liposome immunonanocapsules as labels. The linear detection range for detecting CEA is from 0.5 pg mL-1 to 1 ng mL-1, with a limit of detection of 0.1 pg mL-1. The proposed method also shows good selectivity, excellent reproducibility, and satisfactory recovery in detection of CEA in human serum samples. We believe that this work will lay the foundation for the future development of V2O5-based materials for PEC analysis, and also provide a reasonable design and implementation for the development of PEC immunoassay.


Asunto(s)
Compuestos de Cadmio/química , Antígeno Carcinoembrionario/análisis , Técnicas Electroquímicas/métodos , Inmunoensayo/métodos , Fotoquímica/métodos , Puntos Cuánticos , Ácido Ascórbico/química
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