Detection of B-type natriuretic peptide by establishing a low-cost and replicable fluorescence resonance energy transfer platform.

Aiming at the establishment of a sensitive and specific diagnostic method for early heart failure (HF), we developed a cost-effective fluorescence resonance energy transfer (FRET) platform for the detection of B-type natriuretic peptide (BNP), a characteristic biomarker of HF. Graphene oxide (GO) was selected as the FRET receptor in view of its advantages including commercial availability, low-cost and chemical stability, and dye-modified aptamer was used as the energy donor of FRET as well as in charge of the specific recognition of BNP. Based on the ON (strong emission) and OFF (quenching) states of FRET in the presence and absence of BNP, respectively, specific detection of BNP was achieved in the range 0.074-0.56 pg/mL with a limit of detection as low as 45 fg/mL (3σ). This FRET platform was applied to detect BNP in 45 blood samples to demonstrate its practicability in clinical diagnosis. Compared to the commonly used Siemens method (chemiluminescence immunoassay, CLIA) in hospital, our approach is more accurate and specific for HF diagnosis with areas under the receiver operating characteristic curves of 0.869 (95% CI 0.733-1.00, P < 0.05) vs 0.850 (95% CI 0.703-0.997, P < 0.05) and specificity of 68.8% vs 65.6%. This platform is promising in early diagnosis of HF through ultrasensitive and specific detection of BNP. Graphical abstract To solve the clinical diagnostic problem for early heart failure (HF) which lacks sensitivity and specificity, we established a cost-effective and rapid fluorescence analysis method based on fluorescence resonance energy transfer (FRET) platform for the detection of B-type natriuretic peptide (BNP), a characteristic biomarker of HF.

[Phenolics from traditional Chinese medicine Sargentodoxa cuneata].

AIM: To study the chemical constituents of Sargentodoxa cuneata. METHODS: To isolate compounds with chromatography technology and to elucidate their structures by spectral analysis. RESULTS: Ten phenolics were isolated from Sargentodxa cuneata and their structures were determined as 1-O-(vanillic acid )-6-O-( 3", 5"-dimethoxy-galloyl)-beta-D-glycoside (I), (-)-epicatechin (II), phydroxyphenylethanol ferulate (III), chlorogenic acid (IV), methyl chlorogenate (V), apocynin (VI), vanillic acid (VII), protocatechuic acid (VIII), 3,4-dihydroxy-phenylethanol (IX), tyrosol (X). CONCLUSION: Compound I is new compound, compound III-VI and VIII-X were isolated from Sargentodoxa cuneata for the first time.