Question: Can I use fixed samples as input to the Multiome assay?
Answer: We have performed limited testing of fixed samples in the Multiome assay. Fixation has been attempted at the cell stage before nuclei extraction. Methanol fixation and fixation in 4% PFA showed significantly lower data quality and targeting metrics than using fresh cells. Fixation in 1% PFA for 30 min in PBMC samples showed ATAC results similar to unfixed samples and only a moderate drop in gene expression quality; however, it is unclear if complete fixation can be achieved with only 1% PFA at 30 minutes. These results may not translate well to all sample types and to longer fixation times. Our recommendation is to avoid fixation to maintain optimal product performance.
Products: Single Cell Multiome ATAC + GEX