پديدآورندگان :
Lavaee Parirokh Academic Center For Education, Culture and Research (ACECR)-Mashhad Branch, Mashhad, Iran , Abnous Khalil Academic Center For Education, Culture and Research (ACECR)-Mashhad Branch, Mashhad, Iran / Academic Center For Education, Culture and Research (ACECR)-Mashhad Branch, Mashhad, Iran , Mohammad Danesh Noor Nanotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran / Research Institute of Sciences and New Technology, Mashhad, Iran , Ramezani Mohammad Nanotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran , Alibolandi Mona Pharmaceutical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran , Taghdisi Seyed Mohammad taghdisihm@mums.ac.ir Targeted Drug Delivery Research Center, Mashhad University of Medical Sciences, Mashhad, Irant
كليدواژه :
Acetamiprid , aptamer , dsDNA , gold nanoparticles
چكيده فارسي :
Acetamiprid is an insecticide with a widespread usage. So that, determination of acetamiprid in human serum and water is highly desirable. Here, a novel fluorescent analytical assay was designed for specific and ultrasensitive detection of acetamiprid, based on target-induced release of FAM-labeled complementary strand of aptamer (CS) from aptamer (Apt)/CS conjugate (dsDNA) and three kinds of nanoparticles with opposite effects on the fluorophore (FAM). These nanomaterials are gold nanoparticles (AuNPs), single-walled carbon nanotubes (SWNTs) and silica nanoparticles coated with streptavidin (SiNP-Streptavidin). In the presence of acetamiprid, FAM-labeled CS was released from dsDNA-modified SiNP-Streptavidin complex and accumulated in the supernatant (Phase I) after centrifugation of sample. The fluorescence intensity significantly decreased when the supernatant was added to the environment of SWNTs and AuNPs which are strong fluorescence quenchers (Phase II). So, in this situation the relative fluorescence intensity (Phase I – Phase II) was too much. In the absence of target, dsDNA-modified SiNP-Streptavidin complex remained intact and no FAM-labeled CS was in the supernatant, and consequently, in the environment of AuNPs and SWNTs. So, the relative fluorescence intensity was too low. The designed assay showed high selectivity toward acetamiprid with a limit of detection (LOD) as low as 127 pM. In addition, the analytical method was successfully utilized to detect acetamiprid in serum and water with LODs of 198 and 130 pM, respectively.
