Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Mikrochim Acta ; 191(9): 557, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39174816

RESUMEN

. A sandwich-type photoelectrochemical (PEC) immunosensor based on a ZnO/poly(5-formylindole) (P5FIn)/anthocyanin heterostructure was developed to achieve sensitive background-free detection of the tumor marker CYFRA21-1. ZnO with good photovoltaic properties is combined with narrow bandgap P5FIn to form a p-n type heterojunction. This structure reduces the electron-hole pair recombination, thereby enhancing the photocurrent response of the composite. Anthocyanidins are environmentally friendly natural compounds with excellent antioxidant, redox properties, and remarkable electrochemical activity. After sensitization by anthocyanins, the absorption and utilization of visible light in the composites are enhanced, further improving the PEC luminescence efficiency of the materials. Additionally, boron nitride quantum dots (BN QDs) are combined with Ab2 via polydopamine (PDA) as a secondary antibody marker, enhancing its sensitivity. The biosensor exhibited a linear detection range of 0.001-100 ng mL-1 with a limit of detection (LOD) of 0.00033 ng mL-1. Furthermore, this biosensor demonstrates excellent selectivity, reproducibility, and stability, as well as successful results in analyzing actual human serum samples. This approach provides a feasible method for tumor marker detection.


Asunto(s)
Antocianinas , Antígenos de Neoplasias , Técnicas Biosensibles , Técnicas Electroquímicas , Queratina-19 , Límite de Detección , Óxido de Zinc , Humanos , Técnicas Biosensibles/métodos , Queratina-19/sangre , Queratina-19/inmunología , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Óxido de Zinc/química , Antígenos de Neoplasias/sangre , Antígenos de Neoplasias/inmunología , Antocianinas/química , Puntos Cuánticos/química , Anticuerpos Inmovilizados/inmunología , Biomarcadores de Tumor/sangre , Inmunoensayo/métodos , Polímeros/química , Reproducibilidad de los Resultados , Indoles/química , Procesos Fotoquímicos
2.
Anal Methods ; 16(29): 4995-5002, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38975707

RESUMEN

A novel electrochemical gas sensor for sensitive detection of H2S at room temperature is constructed based on the Fe@Pt/C composite material. The core-shell structured Fe@Pt catalyst was synthesized by a two-step reduction method and physically dispersed in Vulcan XC-72 carbon powders. The core-shell structure increases the effective catalytic surface area of Pt while significantly reducing the usage of the noble metal Pt, leading to improved catalytic performance and decreased production costs. Additionally, the mature screen-printing process is used to coat the catalyst film. A waterproof and breathable PTFE film was used as the substrate and the parameters in the screen printing process were also optimized to achieve the best gas sensing performance of the electrode film. Through the detection of hydrogen sulfide (H2S) with different concentrations, it is found that the sensor strictly shows linear correlation in the range of 1-20 ppm, R2 = 0.99974. Notably, the sensor exhibits high sensitivity (658.45 nA ppm-1) and a low detection limit of 0.33 ppm. Moreover, the consistency and stability of the sensor are satisfactory. The constructed gas sensor is expected to be well applied to industrial H2S detection.

3.
Anal Chem ; 96(21): 8763-8771, 2024 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-38722793

RESUMEN

Proteomics analysis of mass-limited samples has become increasingly important for understanding biological systems in physiologically relevant contexts such as patient samples, multicellular organoids, spheroids, and single cells. However, relatively low sensitivity in top-down proteomics methods makes their application to mass-limited samples challenging. Capillary electrophoresis (CE) has emerged as an ideal separation method for mass-limited samples due to its high separation resolution, ultralow detection limit, and minimal sample volume requirements. Recently, we developed "spray-capillary", an electrospray ionization (ESI)-assisted device, that is capable of quantitative ultralow-volume sampling (e.g., pL-nL level). Here, we developed a spray-capillary-CE-MS platform for ultrasensitive top-down proteomics analysis of intact proteins in mass-limited complex biological samples. Specifically, to improve the sensitivity of the spray-capillary platform, we incorporated a polyethylenimine (PEI)-coated capillary and optimized the spray-capillary inner diameter. Under optimized conditions, we successfully detected over 200 proteoforms from 50 pg of E. coli lysate. To our knowledge, the spray-capillary CE-MS platform developed here represents one of the most sensitive detection methods for top-down proteomics. Furthermore, in a proof-of-principle experiment, we detected 261 ± 65 and 174 ± 45 intact proteoforms from fewer than 50 HeLa and OVCAR-8 cells, respectively, by coupling nanodroplet-based sample preparation with our optimized CE-MS platform. Overall, our results demonstrate the capability of the modified spray-capillary CE-MS platform to perform top-down proteomics analysis on picogram amounts of samples. This advancement presents the possibility of meaningful top-down proteomics analysis of mass-limited samples down to the level of single mammalian cells.


Asunto(s)
Electroforesis Capilar , Proteómica , Electroforesis Capilar/métodos , Proteómica/métodos , Humanos , Escherichia coli/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas/métodos
4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 347-354, 2024 Apr.
Artículo en Chino | MEDLINE | ID: mdl-38660835

RESUMEN

OBJECTIVE: To explore the risk factors affecting the survival and efficacy of patients with acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) transformed from myelodysplastic syndrome (MDS). METHODS: The clinical data of 60 patients with AML-MRC transformed from MDS who hospitalized in The Third Affiliated Hospital of Soochow University from January 2010 to December 2021 were retrospectively analyzed. The demographic data and laboratory parameters, cytogenetic karyotypes, target genes of AML detected by next generation sequence, risk stratification, treatment regimen, therapeutic efficacy and survival outcome were documented. Rank sum test and Chi-square test or Fisher exact test were used to compare the survival and efficacy. The effects of clinical parameters, risk stratification and treatment regimens on the survival and efficacy of the AML-MRC patients were analyzed by univariate and multivariate analysis. RESULTS: The median overall survival (OS) of the AML-MRC patients was 4.5 months, the 1-year OS rate was 28.3%, and the complete remission (CR) rate after treatment was 33.3%. The univariate analysis showed that age≥60 years, leukocytosis, severe thrombocytopenia, poor-risk group and only accepted hypomethylating agents(HMAs) or supportive therapy were the risk factors affecting OS. COX multivariate analysis showed that thrombocytopenia ( HR=4.46), HMAs therapy (compared to transplantation, HR=10.47), supportive therapy (compared to transplantation, HR=25.80) and poor-risk group (compared to medium-risk group, HR=13.86) were independent hazard factors for median OS of patients with AML-MRC. The univariate analysis showed that the risk factors affecting 1-year OS in patients with AML-MRC were age≥60 years, thrombocytopenia, time of transformation from MDS to AML (TTA)≥3 months, fibrinogen-albumin ratio index (FARI)≥0.07, CONUT score≥5, poor-risk group and supportive therapy. Binary logistic regression analysis showed that the independent risk factors for 1-year OS in AML-MRC patients were age≥60 years ( HR=11.23), thrombocytopenia ( HR=8.71), FARI≥0.07 ( HR=5.19) and poor-risk group ( HR=14.00). The risk factors affecting CR of AML-MRC patients in univariate analysis were age≥60 years, thrombocytopenia, FARI≥0.1, CONUT score≥5, poor-risk group and supportive therapy, while binary logistic regression analysis showed that age≥60 years( HR=7.35), CONUT score≥5 ( HR=9.60), thrombocytopenia ( HR=12.05) and poor-risk group ( HR=32.5) were independent risk factors affecting CR of the patients. CONCLUSION: The OS of AML-MRC patients is poor, old age(≥60 years old), supportive therapy, HMA therapy, poor-risk, thrombocytopenia, FARI≥0.07 and CONUT score≥5 may be associated with poor prognosis.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Humanos , Síndromes Mielodisplásicos/complicaciones , Pronóstico , Tasa de Supervivencia , Factores de Riesgo , Persona de Mediana Edad , Progresión de la Enfermedad , Trombocitopenia/etiología , Femenino , Inducción de Remisión , Masculino
5.
Appl Opt ; 63(3): 617-623, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38294372

RESUMEN

We propose an equivalent circuit model of the traveling wave electrode for lithium niobate thin film (TFLN) Mach-Zehnder modulators, in which the distributed capacitance and conformal mapping techniques are applied to calculate the microwave refractive index, microwave loss, and characteristic impedance. Their accuracies are verified by comparing with the results of the finite element method, and the relative errors are less than 3.282%, 1.776%, and 5.334%, respectively. The influence of the electrode's structural parameters on the modulation performances is analyzed, and a 3 dB modulation bandwidth around 84 GHz with an 8-mm-long traveling wave electrode is obtained.

6.
Anal Sci Adv ; 4(5-6): 181-203, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38188188

RESUMEN

Top-down proteomics (TDP) identifies, quantifies, and characterizes proteins at the intact proteoform level in complex biological samples to understand proteoform function and cellular mechanisms. However, analyzing complex biological samples using TDP is still challenging due to high sample complexity and wide dynamic range. High-resolution separation methods are often applied prior to mass spectrometry (MS) analysis to decrease sample complexity and increase proteomics throughput. These separation methods, however, may not be efficient enough to characterize low abundance intact proteins in complex samples. As such, multidimensional separation techniques (combination of two or more separation methods with high orthogonality) have been developed and applied that demonstrate improved separation resolution and more comprehensive identification in TDP. A suite of multidimensional separation methods that couple various types of liquid chromatography (LC), capillary electrophoresis (CE), and/or gel electrophoresis-based separation approaches have been developed and applied in TDP to analyze complex biological samples. Here, we reviewed multidimensional separation strategies employed for TDP, summarized current applications, and discussed the gaps that may be addressed in the future.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...