> For the complete documentation index, see [llms.txt](https://knowledge.illumina.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://knowledge.illumina.com/library-preparation/illumina-single-cell/library-preparation-illumina-single-cell-reference_material-list/000009525.md).
# Representative cDNA QC traces for Illumina Single Cell 3’ RNA Prep
**In the Illumina Single Cell 3' RNA Prep workflow, cDNA peaks, distributions, and average fragment sizes can vary based on sample type and experimental conditions.**
The following TapeStation traces serve as representative examples of satisfactory cDNA QC profiles generated during the Check QC Product step in the [Illumina Single Cell 3' RNA Prep workflow](https://support.illumina.com/sequencing/sequencing_kits/illumina-single-cell-prep/documentation.html).
**Figure 1**. Human peripheral blood mononuclear cells (PBMCs)
**Figure 2**. Human HEK 293T and mouse NIH 3T3 cell line mixture
**Figure 3**. Mouse frozen tissue: unfixed brain nuclei
**Figure 4**. Mouse frozen tissue: DSP-methanol fixed brain nuclei
**Figure 5**. Mouse frozen tissue: unfixed mouse diaphragm
**Figure 6**. Mouse frozen tissue: unfixed mouse heart
**Figure 7**. Mouse frozen tissue: unfixed lung nuclei
**Figure 8**. Mouse frozen tissue: DSP-methanol fixed lung nuclei (1-month storage)
For example final library traces produced using similar sample types, see [Representative library QC traces for Illumina Single Cell 3' RNA Prep](/library-preparation/illumina-single-cell/library-preparation-illumina-single-cell-reference_material-list/000009528.md).
For more information related to cDNA QC product assessment refer to:
* [Illumina Single Cell 3' RNA Prep cDNA QC best practices](/library-preparation/illumina-single-cell/library-preparation-illumina-single-cell-reference_material-list/000009523.md)
* [Assessing cDNA QC in Illumina Single Cell 3' RNA Prep](/library-preparation/illumina-single-cell/library-preparation-illumina-single-cell-reference_material-list/000009524.md)
* [Illumina Single Cell 3' RNA Prep Training Packet](https://support.illumina.com/sequencing/sequencing_kits/illumina-single-cell-prep.html)
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| *For any feedback or questions regarding this article (Illumina Knowledge Article #9525), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000009525%20-%20Library%20Preparation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |
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