This technical note utilizes FQ (3-2-(furoyl quinoline-2-carboxaldehyde) dye for sample labeling and a laser-induced fluorescence (LIF) detector with 488nm solid-state laser and an emission filter of 600nm for sample detection to increase the sensitivity of AAV capsid purity analysis. It demonstrates the capability of this CE-SDS-LIF method for purity analysis of AAV viral proteins to as low as 1X1010 GC/mL with easy sample preparation, excellent resolving power, good repeatability and linearity of absorbance response to sample concentration.