gradient optimization

[mariia.maak]

Hello!

Can anyone recommend a book/paper/tutorial/video on gradient optimization?

Thank you,
Mariia

[Consumer Products Guy]

Hello! Can anyone recommend a book/paper/tutorial/video on gradient optimization? Thank you, Mariia

I cannot help with your question.

I will state that I got into HPLC in its early years in my R&D job, and my main general "hint" early in methods development is to use more of the stronger solvent in the gradient, and then back off to lower percentages to meet your needs.

And one "for sure" is to make the equilibration volume/time before next injection long enough, and here more is better than not enough.

[Multidimensional]

Suggest you try "Dry Lab" software. It is very good basic software which can be used along with some of the classic texts on HPLC (e.g. "Practical HPLC Method Development" by Snyder et al.) to learn the fundamental basics of how gradient composition changes result in changes to the chromatography. These HPLC basics are best learned by 'doing', hands-on, not reading about, but the texts and software may help you better understand the concepts and encourage you to try your own experiments to verify. Solid practical experience coupled to accurate information usually leads to faster learning.

In addition to the above, please make sure you have a solid foundation of understanding:
T0 https://hplctips.blogspot.com/2011/05/determination-of-hplc-column-dead-time.html,
K prime https://hplctips.blogspot.com/2015/06/k-prime-also-known-as-capacity-factor.html and
how delay volume effects gradient delay https://hplctips.blogspot.com/2017/02/determine-hplc-system-dwell-volume.html too.

[mariia.maak]

Hello! Can anyone recommend a book/paper/tutorial/video on gradient optimization? Thank you, Mariia

I cannot help with your question.

I will state that I got into HPLC in its early years in my R&D job, and my main general "hint" early in methods development is to use more of the stronger solvent in the gradient, and then back off to lower percentages to meet your needs.

And one "for sure" is to make the equilibration volume/time before next injection long enough, and here more is better than not enough.

Thank you very much, I found it useful!

[mariia.maak]

Suggest you try "Dry Lab" software. It is very good basic software which can be used along with some of the classic texts on HPLC (e.g. "Practical HPLC Method Development" by Snyder et al.) to learn the fundamental basics of how gradient composition changes result in changes to the chromatography. These HPLC basics are best learned by 'doing', hands-on, not reading about, but the texts and software may help you better understand the concepts and encourage you to try your own experiments to verify. Solid practical experience coupled to accurate information usually leads to faster learning.

In addition to the above, please make sure you have a solid foundation of understanding:
T0 https://hplctips.blogspot.com/2011/05/determination-of-hplc-column-dead-time.html,
K prime https://hplctips.blogspot.com/2015/06/k-prime-also-known-as-capacity-factor.html and
how delay volume effects gradient delay https://hplctips.blogspot.com/2017/02/determine-hplc-system-dwell-volume.html too.

Thanks! It was very helpful!

[James_Ball]

Oh how I wish I had the internet when I was learning these things

[JackSilver]

Also, please look at this paper:
https://pubs.acs.org/doi/10.1021/acscombsci.8b00187

It is intended for preparative chromatography. It lists some methods of calculating gradients from scouting runs, and introduces a technique that uses a fairly simple "calibration" between the analytical and preparative systems. It generates a focused gradient for a particular compound of interest.

[Multidimensional]

This needs repeating for new users who find this post.... regarding such basic questions as this. A classic text should be initially consulted, which should be required reading for ALL users of an HPLC system, "Practical HPLC Method Development". It has a very nice, simple explanation for how to start the process of gradient analysis and optimization. *I recommend the older, first edition of the book. Simple is best and that copy sticks to the basics better than any others (you know, those HPLC fundamentals that almost no one ever seems to learn about). We routinely hand out extra copies of the books, when we can get them, to the students in our classes. Now, if we could just get people to read them, progress would be made...