Visual upconversion nanoparticle-based immunochromatographic assay for the semi-quantitative detection of sibutramine

Highly resistant and sensitive colorimetric immunochromatographic assay for sibutramine (SBT) illegally adulterated into diet food based on PDA/AuNP labelling

“…4) with more than one order of magnitude improvement in sensitivity compared with the previous study. 9 The metabolite of M 1 was confirmed to be cross-recognized by mAb with an IC 50 of 1.23 ng mL −1 and a CR value of 56.1% (Table S1 †). The metabolite M 2 could not be recognized by the mAb, which might be explained by the different epitope lacking methylamine (Fig.…”

“…8 Zhang et al developed a monoclonal antibody (mAb) against SBT by using a derivative of SBT as a hapten, and the resulting IC 50 of the corresponding ELISA is 2.1 ng mL −1 . Recently, for the determination of SBT by ICA, upconversion nanoparticles (UCNPs) 9 and colloidal AuNPs 10 have been used for signal amplification for improved sensitivity. In contrast with UCNPs, which endow strong and unique luminescence properties, 11 AuNPs are preferred due to the advantages of visual analysis, availability, cost effectiveness, stability, easy surface modification, and shape- and size-dependent optical properties.…”

Colorimetric and Reverse Fluorescence Dual-Signal Readout Immunochromatographic Assay for the Sensitive Determination of Sibutramine

“…15,16 Currently, LFIA has been used for the qualitative and semiquantitative detection of SBT based on the antigen−antibody biochemical interaction. 17,18 In these systems, a signal reporter of gold nanoparticles offers excellent stability and optical properties while fluorescent quantum dots (QDs) offer high fluorescence quantum yield and tunable emission wavelength. Yet background signal intensity limits ultrasensitive detection.…”

“…Lateral flow immunochromatographic analysis (LFIA) is a rapid, low-cost, and convenient detection method, which has excellent performance in food safety detection and on-site diagnosis. , Currently, LFIA has been used for the qualitative and semiquantitative detection of SBT based on the antigen–antibody biochemical interaction. , In these systems, a signal reporter of gold nanoparticles offers excellent stability and optical properties while fluorescent quantum dots (QDs) offer high fluorescence quantum yield and tunable emission wavelength. Yet background signal intensity limits ultrasensitive detection. , For micromolecular analyte detection, current LFIA presents a competitive mode called “turn-off”, and there is a negative correlation between the measured signal intensity and target concentration. , The limit of detection (LOD) of LFIA in “turn-off” mode is defined as the corresponding concentration of analytes causing the apparent signal to completely disappear .…”