Target-Recycling-Amplified Colorimetric Detection of Pollen Allergen Using Non-Cross-Linking Aggregation of DNA-Modified Gold Nanoparticles.
Chia-Chen ChangGuoqing WangTohru TakaradaMizuo MaedaPublished in: ACS sensors (2019)
Increasing prevalence of pollen allergies has raised concerns about human health. Development of a facile and precise method to detect pollen allergens would thus be of significance for environmental assessments and medical diagnoses. Here we report a sensitive colorimetric method to detect the Japanese cedar pollen allergen, Cry j 2. The method consists of two steps: a signal amplification based on the catalytic DNA hairpin self-assembly, followed by a signal transduction using the salt-induced non-cross-linking aggregation of gold nanoparticles densely modified with short DNA. The assay exhibits a detection limit of 0.2 ng/mL, which is 130-fold greater than that of the previously reported one. Moreover, the assay enables the detection of Cry j 2 spiked in soil solutions by avoiding any interference from the contaminants. The signal amplification system includes an anti-Cry j 2 DNA aptamer, which accounts for the absence of false responses to five nontarget allergen proteins. The present method could be of general applicability to various proteins by using appropriate aptamers.
Keyphrases
- gold nanoparticles
- nucleic acid
- label free
- circulating tumor
- human health
- reduced graphene oxide
- cell free
- single molecule
- risk assessment
- loop mediated isothermal amplification
- sensitive detection
- real time pcr
- healthcare
- high throughput
- climate change
- highly efficient
- circulating tumor cells
- quantum dots
- single cell
- diabetic rats
- crystal structure
- stress induced
- cell wall