Patent ID: 7682782

Claim:
A method for detecting a plurality of fluorophore species on a biological probe array using a single excitation source scanner, comprising: (a) providing an biological probe array comprising at least two fluorophores, wherein said at least two fluorophores are semiconductor nanocrystals and each has a different extinction coefficient, (b) providing a scanner comprising a single excitation beam source; (c) setting the excitation beam comprising an excitation wavelength at a first power level that elicits an optimal signal to noise ratio response from a first fluorophore having a first extinction coefficient; (d) scanning the biological probe array with the excitation beam at the first power level, thereby eliciting a light emission at a first wavelength from the first fluorophore; (e) detecting the first emission wavelength emitted from the biological probe array; (f) setting the excitation beam comprising the excitation wavelength at a second power level different than the first power level, wherein the second power level elicits an optimal signal to noise ratio response from a second fluorophore; and (g) scanning the biological probe array with the excitation beam at the second power level, thereby eliciting a light emission at a second wavelength from the second fluorophore which is at a different wavelength from the first emission wavelength; (h) detecting the second emission wavelength emitted from the biological probe array; thereby detecting a plurality of fluorophores on the biological probe array.