DNA Barcode Quantification As a Robust Tool for Measuring Mixing Ratios in Two-Component Systems

For many manufacturing processes, correct mixing compositions are crucial to guarantee product quality. However, the analysis of mixing ratios based on component balances can be challenging and requires extensive infrastructure. DNA barcodes have been previously proposed as low-cost markers for product authenticity, and we show here that the quantification of such barcodes via a quantitative real-time polymerase chain reaction (PCR) enables the determination of mixing ratios in a range of liquid and polymeric products. To enable the distribution of the DNA within the various matrixes, the biochemical is encapsulated in silica nanoparticles and distributed within the matrix of the raw material. If both raw materials of a two-component mixture contain such barcodes, the composition of the mixture can be determined from the relative concentration of the barcodes via multiplex PCR reactions, irrespective of the sampling volume and for a wide range of initial barcode concentrations (10 ppm to 10 ppb). As an application example, we use the barcodes to determine the mixing ratios of cross-linked and multicomponent polysilicon products.