In the last years, the development of methods based on the direct introduction of cosmetic samples into the instruments is a tendency [27–29].
Several advantages can be observed when this strategy is used: (i) no (or minimum) dilution of the samples, which allow that excellent limits of quantification can be achieved; (ii) minimum manipulation of the samples, which minimize their contamination and the loss of the analytes during the analytical process; and (iii) increase of productivity, since the time-consuming step of sample preparation is
eliminated.