Sample management

The first step in sample preparation is to homogenize the tissues or cells to promote the dissolution of biological molecules (e.g. DNA, RNA, proteins). The material is then purified and concentrated using various chemical and mechanical methods to remove impurities such as lipids or proteins that may interfere with the analysis. Cooling is used to ensure proper stability and integrity during processing, and if necessary, enzymatic treatment is performed before sample preparation.

During sample qualification, the integrity and purity of DNA and RNA molecules are verified using various molecular biology methods. DNA quality can be measured by long-chain fragments and absorbance changes, while gel electrophoresis is often used for RNA qualification to ascertain the degree of fragmentation of the sample. We measure purity and concentration to ensure the optimal starting material for downstream applications such as PCR or sequencing.

During library preparation, specific fragments are selected from the desired biological sample (e.g. genomic DNA or RNA from a transcriptome) and ligated with adaptors to enable the sequencing process. DNA/RNA fragments are enhanced by PCR or other amplification methods, ensuring the desired volume and specificity. The quality and complexity of the library are controlled and then prepared for sequencing to obtain accurate and reliable data using next-generation sequencing (NGS).