# Converting ng/µl to nM when calculating dsDNA library concentration

Some standard Illumina libraries, such as Nextera, require the use of dsDNA-specific fluorescent dye methods for accurate quantification. These methods typically measure dsDNA concentration in ng/µl. To convert from ng/µl to nM for cluster generation, follow the instructions below\.1. Determine the average size of the library by running it on an Agilent Technologies 2100 Bioanalyzer.\
2\. Use the following formula to convert from ng/μl to nM:

![](https://761066130-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGM9W2DuBTgEXv1ClCm8H%2Fuploads%2Fgit-blob-6ccf3d06b43bab779729a9de201f1cf4e7201362%2Fimage1.jpg?alt=media\&token=a79efa39-5616-49d2-bcdb-0ced501d554a)

\
\
\ <br>

|                                                                                                                                                                                                                                                                                                                                                                              |
| :--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------: |
| *For any feedback or questions regarding this article (Illumina Knowledge Article #1240), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000001240%20-%20Library%20Preparation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://knowledge.illumina.com/library-preparation/dna-library-prep/library-preparation-dna-library-prep-reference_material-list/000001240.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.