Human C4b ELISA Kit (Complement C4-B) is a single-wash 90-min Simplestep used to quantify Human C4b (Complement C4-B) with a sensitivity of 34,83 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 - Validated on a number of sample types including cerebrospinal fluid (CSF).