Detection of Cryptosporidium parvum Oocysts on Fresh Produce Using DNA Aptamers

摘要: There are currently no standard methods for the detection of Cryptosporidium spp., or other protozoan parasites, in foods, and existing often inadequate, with low variable recovery efficiencies. Food testing is difficult due to concentrations difficulty eluting parasites from some lack enrichment methods, presence PCR inhibitors. The main objectives present study were obtain DNA aptamers binding oocyst wall C. parvum, use detect this parasite foods. selected against parvum oocysts using SELEX (Systematic Evolution Ligands by EXponential enrichment). Ten rounds selection led discovery 14 aptamer clones high affinities oocysts. For detecting parasite-bound aptamers, a simple electrochemical sensor was employed, which used gold nanoparticle-modified screen-printed carbon electrode. This aptasensor fabricated self-assembling hybrid thiolated ssDNA primer anti- aptamer. Square wave voltammetry employed quantitate range 150 800 oocysts, limit approximately 100 sensitivity specificity developed suggests that novel method very promising identification on spiked fresh fruits, as compared conventional such microscopy PCR.