TY - RPRT TI - Three-layer matrix/sample preparation method for MALDI MS analysis of low nanomolar protein samples. AU - Bernd O Keller AU - Liang Li PY - 2006 DO - 10.1016/j.jasms.2006.02.012 UR - https://pubmed.ncbi.nlm.nih.gov/16580842/ ID - 16580842 ER -