Development of disposable biosensing strips for the quality control of economic agricultural products

Two types of disposable sensing strips were developed for the quality control of two economic agricultural products, tea and moth orchids. The sensing strip for tea quality is a screen-printed carbon-paste disposable electrode that can be incorporated into a flow injection manifold to estimate tea fermentation degrees based on the redox potentials of tea infusions. The flow-injection analytical manner reduced the adsorption of polyphenols on the electrode surface, reproducible (CV<1.2%) and high-throughput analytical results (>20 hr-1) were obtained. For pouchong tea samples with different fermentation degrees, the data show a high correlation with those obtained by HPLC.he second one is an immunochromatographic strip for detecting the Cymbidium mosaic virus in moth orchids (phalaenopsis spp.). To visualize the immunochromatographic process, polyclonal antibodies against the coat protein of the virus were attached onto 40nm gold nanoparticles. In the present study, myoglobin was immobilized onto the gold nanoparticles to enhance the luminol-H2O2 chemiluminescence by the prosthetic heme group of myoglobin.