![Kits for the preparation of Illumina libraries - Difficult samples](https://www.clinisciences.com/pt/upload/embedding-paraffin-kqchet.jpg)
Kits for the preparation of Illumina libraries - Difficult samples
The first step of a Next Generation Sequencing (NGS) is the preparation of a DNA bank. And for this NGS sequencing to be successful, the DNA bank must be of high quality. However, not all samples will yield good quality DNA for a good DNA bank. We then talk about difficult samples. These include FFPE samples, cell-free DNA samples or very small samples (also called single cells). Although these samples deliver DNA of poor quality and/or in very small quantities, their analysis gives results that are not possible with other samples. Examples include circulating tumour DNA or tumour biopsies. When starting with DNA in limited quantities or of variable quality, the bank preparation method must be precise and efficient, avoiding purification steps that reduce sample recovery.