Rat Retinol Binding Protein 4 ELISA Kit is a single-wash 90-min Simplestep used to quantify Rat Retinol Binding Protein 4 with a sensitivity of 3,07 pg/ml. The assay uses a simple mix-wash-read protocol with just one incubation and one wash step. - Colorimetric Sandwich ELISA - 450 nm readout : works on any standard plate reader.