Evaluation of the quality of formulations containing lactase (β-galactosidase) employing gel electrophoresis and cell phone

A quantification method of the lactase enzyme in pharmaceutical formulations is proposed employing digital images obtained from a cell phone camera and processed using the colorimetric application.The use of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) made it possible to identify the lactase enzyme, to fractionate possible protein impurities and to evaluate the degradation of lactase present in the analyzed formulations.In addition, gel electrophoresis made it possible to determine lactase free of matrix interference.The proposed method presented limit of quantification of 0.002 mg lactase (0.03 FCC), using external calibration.Recoveries of lactase added to the samples were in the range 78-104%.The concentrations found in different pharmaceutical formulations samples containing lactose were in the range 7-621 mg (104-9319 FCC).The relative standard deviations (RSD) were in the range of 3-13%.Of the six samples analyzed, only two (#S2 and #S5) were in agreement with the sample label description.