Abstract: The present invention centers upon a novel “molecular amplification spike,” which is an admixture of two components, namely, an aliquot of a quantity of a molecule, composition, compound or element of interest (an “analyte”) in its natural isotopic state and an aliquot of an isotopically enriched form of the same molecule, composition, compound or element. The molecular amplification spike contains 20% natural-abundance isotope, balance enriched isotope. The molecular amplification spike may optionally contain more than 20% natural-abundance isotope, with concomitantly reduced balance of enriched isotope. Such an admixed spike, when added to a sample prior to mass spectrometric analysis of that sample, creates new and significantly improved percentage of errors and quantification or confirmation of the absence of the molecule, composition, compound or element of interest in the sample.