Using solution-based calibration for the multi-element determination of trace impurities in high-purity platinum. For the mass spectrometric measurements, a quadrupole-based LA-ICP-MS instrument was coupled with an ultrasonic nebulizer (USN). Due to the lack of a high-purity blank platinum sample, quantification of the results of LA-ICP-MS measurements was carried out using the standard additions mode in solution-based calibration. In order to achieve matrix matching, the multi-element standard solutions (with different concentrations of analytes) were nebulized successively with a USN. Simultaneously the high-purity platinum target was ablated with a focused laser beam during solution calibration with the USN. The mass spectrometric method developed was validated using a platinum standard reference material (NIST SRM 681). The analytical results of the LA-ICP-MS of SRM 681 Platinum are in good agreement with the certified values.