The Qubit 4 Fluorometer detects fluorescent dyes specifically bound to the target molecule. It uses two Light sources 470 and 635 nm, two Excitation filters 430-495 nm and 600-645 nm, two Emission filters 510-580 nm and 665-720 nm. Qubit Assays can distinguish dsDNA from ssDNA, large RNA molecules (rRNA or mRNA) from small RNA molecules (microRNA and siRNA) or intact from degraded RNA, even in extremely small amounts or in the presence of contaminants. Qubit Fluorometers are orders of magnitude more sensitive than UV absorbance, depending on the assay kit you can measure samples at concentrations of: dsDNA 0.005-4000 ng/µL, ssDNA 0.01-240 ng/µL, RNA 0.2-20000 ng/µL, microRNA 0.025-150 ng/µL and protein 12.5-20000 µg/µL.