Patent ID: 8187820

Claim:
A detection method using nanoaggregate-embedded beads, comprising steps of: a) Adding a Raman dye into a solution of metal nanoparticles and varying a pH value of the solution of metal nanoparticles and controlling a concentration of the Raman dye to generate nanoaggregates, wherein a size of each of the nanoaggregates is adjusted by varying the pH value of the solution of metal nanoparticles, wherein the pH value of the solution of metal nanoparticles is ranged from 7 to 12, and the concentration of the Raman dye is controlled to be between 0.1×10 −6 M and 5×10 −6 M, and the average size of the nanoaggregate is ranged from 20 nm to 80 nm; b) coating the nanoaggregates with an inorganic oxide to obtain nanoaggregate-embedded beads; c) conjugating the nanoaggregate-embedded bead with a probe molecule to form a sensor bead; d) detecting Raman spectra of the product formed by binding of the sensor bead and an analyte in a sample; and e) determining whether the analyte exists in the sample according to the Raman spectra.