On-target ultrasonic digestion of proteins

: Santos HM, Kouvonen P, Capelo JL, Corthals GL

: 2013

Proteomics

: PROTEOMICS

: 9

: 13

: 9

: 1423

: 1427

: 5

: 1615-9853

DOI: https://doi.org/10.1002/pmic.201200241

In the present work, we report a novel on-target protein cleavage method. The method utilizes ultrasonic energy and allows up to 20 samples to be cleaved in 5 min for protein identification and one sample in 30 s for on-tissue digestion. The standard proteins were spotted on a conductive glass slide in a volume of 0.5 L followed by 5 min of ultrasonication after trypsin addition. Controls (5 min, 37 degrees C no ultrasonication) were also assayed. After trypsin addition, digestion of the tissues was enhanced by 30 s of ultrasonication. The samples were analyzed and compared to those obtained by using conventional 3 h heating proteolysis. The low sample volume needed for the digestion and reduction in sample-handling steps and time are the features that make this method appealing to the many laboratories working with high-throughput sample treatment.