Development of a system for detecting cardiac troponin I by background fluorescence quenching based on internal filtration effect.

The present study sought to develop a cardiac troponin I (cTnI) detection system based on background fluorescence quenching of internal filtration effect (IFE) and study the influence of IFE on the sensitivity of cTnI detection. Three nanogold materials were synthesized as fluorescence quenchers, and rhodamine 6 G (R6G) and Cy5 were used as fluorescence probes. Six experimental systems were established to detect cTnI in negative serum test solutions and clinical serum samples.

Combined detection of SARS-CoV-2 neutralizing antibodies and specific IgG in plasma based on SERS magnetic sensor.

In this study, a surface-enhanced Raman spectroscopy (SERS) magnetic sensor is established based on SERS principle and magnetic separation technology, and a highly sensitive, simple and fast method for quantitative detection of neutralizing antibodies (nABs) and specific IgG of SARS-CoV-2 in plasma is established combined with immunoassay. Two kinds of Raman nanospheres (RNPs) with different characteristic Raman shifts are used as signal sources and coupled to ACE2 and anti-IgG (FC) antibodies respectively, and magnetic beads are coupled to RBD. The competitive relationship between ACE2 and nABs, the binding relationship between specific IgG and anti-IgG (FC) antibodies are determined.

Study on the performance of novel nanomaterials for detection of biomarkers such as PCT based on immunochromatography sensitivity.

In this study, by comparing the UV-vis spectral characteristics of colloidal gold and colloidal gold enhancer, and their differences as immunochromatographic tracers in the qualitative detection of PCT, IL-6, Hp and quantitative determination of PCT performance, the factors that may affect the sensitivity were discussed. The results show that the absorbance at 520 nm of CGE diluted 20-fold and colloidal gold diluted 2-fold were comparable, and the sensitivity of CGE immunoprobe for qualitative detection of PCT, IL-6 and Hp was higher than that of colloidal gold immunoprobe, and the reproducibility and accuracy of both immunoprobes for quantitative detection of PCT were good. Indicating that the high sensitivity of CGE immunoprobe detection is mainly due to the absorption coefficient of CGE at 520 nm is about 10 times that of colloidal gold immunoprobe, CGE has stronger light absorption capacity and stronger quenching effect on rhodamine 6 G on the nitrocellulose membrane surface of the test strip.

Synchronous detection of IgG subtypes based on SERS combined with immunoassay.

In this study, a rapid, simple, highly sensitive and anti-interference method for the joint detection of four IgG subtypes is established by using Raman microspheres with four characteristic Raman spectra. The results show that the concentrations of IgG1 in the range of 0-1500 ng ml, IgG2 in the range of 0-1100 ng ml, IgG3 in the range of 0-88.7 ng ml, IgG4 in the range of 0-77.

Role of glutamine in the mediation of E-cadherin, p120-catenin and inflammation in ventilator-induced lung injury.

Background: Ventilator-induced lung injury (VILI) is commonly associated with barrier dysfunction and inflammation reaction. Glutamine could ameliorate VILI, but its role has not been fully elucidated. This study examined the relationship between inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor [TNF]-α, and IL-10) and adherens junctions (E-cadherin, p120-catenin), which were ameliorated by glutamine in VILI, both in vitro and in vivo.