title: CdTe/CdSe quantum dots improve the binding affinities between α-amylase and polyphenols.
abstract: People exposed to engineered nanomaterials have potential health risks associated. Human α-amylase is one of the key enzymes in the digestive system. There are few reports about the influence of quantum dots (QDs) on the digestive enzymes and their inhibition system. This work focused on the toxic effect of CdTe/CdSe QDs on the interactions between α-amylase and its natural inhibitors. Thirty-six dietary polyphenols, natural α-amylase inhibitors from food, were studied for their affinities for α-amylase in the absence and presence of CdTe/CdSe QDs by a fluorescence quenching method. The magnitudes of apparent binding constants of polyphenols for α-amylase were almost in the range of 10(5)-10(7) L mol(-1) in the presence of CdTe/CdSe QDs, which were higher than the magnitudes of apparent binding constants in the absence of CdTe/CdSe QDs (10(4)-10(6) L mol(-1)). CdTe/CdSe QDs obviously improved the affinities of dietary polyphenols for α-amylase up to 389.04 times. It is possible that the binding interaction between polyphenols and α-amylase in the presence of CdTe/CdSe QDs was mainly caused by electrostatic interactions. QDs significantly influence the digestive enzymes and their inhibition system.
authors.affiliation: Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai 200032, PR China. ni.xiaoling@zs-hospital.sh.cn
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Ni
mesh_terms: D019187:Cadmium Compounds / Q000633:toxicity*; D004064:Digestive System / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D036103:Nanotechnology; D059808:Polyphenols / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D045663:Quantum Dots; D018036:Selenium Compounds / Q000633:toxicity*; D013050:Spectrometry, Fluorescence; D055672:Static Electricity; D049490:Systems Biology; D013691:Tellurium / Q000633:toxicity*; D000516:alpha-Amylases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D019187:Cadmium Compounds; D059808:Polyphenols; D018036:Selenium Compounds; C058667:cadmium selenide; D000516:alpha-Amylases; D013691:Tellurium; C028337:cadmium telluride