Specifically, trypsin was immobilized on to 20 μm ID polymer-wall coated capillaries (OTERs), cleaving an isolated small cell lung cancer (SCLC) marker (ProGRP) into peptides that were subsequently separated by high peak capacity PLOT LC columns (10 μm ID [31]), with cleavage and LC-MS run time of totally 40 minutes. Here, GRP is linked to small cell lung carcinoma.