The dataset contains data that was generated using a commercial mass spectrometer Synapt G2-Si (Waters) equipped with an in-house developed AP-MALDI ion source. MassLynx software (ver. 4.1; Waters) was used to collect and process the data. Surface tension data were acquired on a commercial tensiometer K-12 (Kruess). The manuscript in preparation at time of the data deposit is entitled 'The composition of liquid AP-MALDI MS matrices and its effect on ionization' by P.Ryumin, R.Cramer contains the methods section where the exact procedures of the data acquisition are described.