The Establishment Of New Detection Method Based On Quantum Dot Fluorescent Lateral Chromatography Strips

(1) The preparation of water-soluble CdSe quantum dotsThis experiment did a simple preliminary optimized choice of the synthesis time, synthesis temperature as well as annealing temperature during CdSe quantum dots synthesis. The results showed that the the length of synthesis time and the height of synthesis temperature had a siganificant impact on the half peak width and fluorscent spectra of CdSe quantum dots:longer synthesis time can generate comparatively small half peak width and more symmetrical fluorscent spectra peak as well as more obvious red shift than shorter synthesis time, that was to say the longer synthesis time was beneficial to the uniform distribution of CdSe quantum dots particle size; Look from the synthesis temperature, there was an obvious decrease on half peak width under high synthesis temperature than that of under low synthesis temperature.With the same reason that the high synthesis temperature was beneficial to the uniform distribution of CdSe quantum dots particle size.(2) quantum dot-based fluorescent lateral flow test strip to detecte melamineWe employed the quantum dot-based fluorescent lateral flow test strip to achieve the rapid detection of melamine based on the competitive principle. The results showed that this method presented good quantitative detection linear relationship, great obvious specificity, short testing time (within 5 min), small volume of sample (only needed 70 uL),and high detection sensitivity. The final naked-eye detection limit of the proposed method could reach to 10 ppb and this method could also be used for the actual samples testing. In addition, we vertified the stability of this method by testing hydrochloric acid. The results showed that the method had good linear relationship for detecting hydrochloride acid and a 10 ppb naked-eye detection limit could be reached.(3) the thrombin detectionThis experiment established the fluorescence resonance energy transfer system between quantum dots and colloidal gold and then combined this detection platform with lateral chromatography strip platform to realize rapid ultrasensitive detection of thrombin. The results showed that this method which was convenient, safe and reliable holded good linear relationship, graet specificity, fast detection (within 6 min), small volume of sample (only needed 80 μL) and high detection sensitivity. The final naked-eye detection limit of the proposed method could be defined as 0.135 nM and this method could also be used for the actual sample testing.