The determination of the number of sequencing-ready molecules present after library preparation is an important step in the next generation sequencing (NGS) workflow and has a strong influence on the success of a sequencing run.

qPCR is considered to be the most accurate and effective method of library quantitation, providing considerably higher consistency and reproducibility of quantitation. The qPCR-based NEBNext^_® Library Quant Kit quantitates only those molecules that contain both adaptor sequences, thereby providing a more accurate estimate of the concentration of the library molecules that can be sequenced.