The Low Range Cas9 ELISA Assay is an ultra-sensitive enzyme-linked immunosorbent assay (ELISA) specifically designed for the detection and quantification of low levels of S. pyogenes Cas9 protein in cell culture lysates. This assay is ideal for researchers who require precise measurement of minimal Cas9 expression, making it a valuable tool for CRISPR/Cas9 gene editing studies and experimental screening.