Abstract: The present invention discloses a method for complete tracking of a set of biological samples containing DNA or RNA through the use of molecular barcode identification during the course of laboratorial workflow, wherein the sample is contacted with primers comprising a molecular barcode and a universal primer sequence immediately after its collection and the amplification of the target regions occurs concomitantly to the barcode insertion, in one or both ends of said target region, in the same annealing temperature through a one step PCR. Finally, the invention also discloses kits for collecting biological samples containing DNA or RNA.