Target coatings and desorption surfaces in biomolecular MALDI-MS.

MALDI-MS is an extremely flexible technique and can be synergistically used in conjunction with established bioanalytical methods such as PAGE or SPR. To that end, slight modifications on the sample target plate may be necessary. Those can involve the use of hydrophobic coatings for improved sample deposition and desalting or that of sensor surfaces for on-target bioaffinity experiments. In particular the latter have evolved considerably over the past years. Surface coatings using polysaccharide or polycarboxylate hydrogels were adopted from unrelated techniques and they proved very suitable for bioaffinity MS. The developments concerning target modification and derivatization are reviewed.