Comparison of different linear calibration approaches for LC-MS bioanalysis

► Two-concentration linear calibration is better than multi-concentration one. ► One curve may have more failed runs and higher variation at low end than two curves. ► A new in-between approach is proposed to take advantage of the two common ones. ► Maximum tolerable quadratic behaviour in linear calibration has been determined. ► Two-concentration linear calibration has potential use in regulated bioanalysis.