Among the various calibration strategies available with ICP-based techniques, the on-line modalities stand out. The use of on-line calibrations plays an essential role in correcting analytical signal suppression (or enhancement) due to matrix effects and signal fluctuations due to temporal variations in the plasma. On-line calibrations are based on the continuous merging of sample and standard solutions (or internal standard) by flow injection strategies improving the mixing of both solutions, reducing their consumption and providing high repeatability. Recently, the novel MultiNeb® nebulizer has been developed which allows a high mixing efficiency between two liquids, miscible or immiscible, since the mixing takes place under turbulent conditions of high pressure at the tip of the nebulizer. The next technical note shows the better analytical performance of the MultiNeb® compared with other nebulizers when on-line mixing is performed.