As the per base read cost of next-generation sequencing (NGS) has decreased, the library preparation cost, especially in high-throughput applications such as, single cell analysis, has become a larger portion of the total cost.
Single-cell analysis provides whole genome and transcriptome sequencing from a single cell. Because single cells have small quantities of DNA and mRNA, any degradation, sample loss or contamination can have profound effects on the quality of sequencing results. Recent technical improvements have made single-cell analysis and sequencing a powerful tool. These technologies include the use of automated low‑volume liquid handlers such as TTP Labtech’s mosquito HTS.
Nextera XT sample prep kits (Illumina, Inc., USA) are commonly used to prepare DNA libraries for NGS. Insert sizes of generated libraries are dependent on the ratio of
DNA and tagmentation enzyme in the reaction. Therefore having a precise and accurate liquid handler is essential in library prep workflows. Normalisation of the libraries prior to sequencing is necessary to ensure there is a similar number of reads and coverage of base pairs per each sample.
To assure high accuracy and precision, most library preparation protocols recommend volumes that are within the range of manual pipettes or that of large volume liquid handlers. TTP Labtech’s mosquito nanolitre to microlitre liquid handlers enable the reduction of samples and reagents volumes without compromising the quality of the libraries.
This application note presents data from Prof. Stephen Quake’s lab, Stanford University, USA on the use of automated low-volume liquid handlers for miniaturising DNA normalisation and library prep volumes for single cell analysis.
“mosquito HTS has reduced hands‑on time for normalisation and library prep from two weeks to a single day while increasing the accuracy and lowering the cost at the same time.” Dr. Rahul Sinha, Prof. Irving Weissman’s group, Stanford University