As a baker, I’m constantly scaling up good recipes, and as a scientist you might need to do the same. Prep LC is all about scaling up – and let me tell you from experience that scaling up is often needed in both a kitchen and lab setting.
As a baker you always test a new recipe with a few test batches not only see if you like the baked good you made overall, but to check the ratios, flavor profile and texture. If the baked good isn’t right you either start again and adjust the ingredients and cook, or just trash it (hopefully not).
After several trial-and-error attempts you just might perfect that sought after chewy – but not too chewy – chocolate chip cookie recipe.
Of course, you need to check the reproducibility of this perfected cookie (I mean you can’t expect to scale up this recipe if it’s not consistent batch to batch) – so you do a few more test runs, ask a few more taste testers for their approval, and hopefully you’ve nailed it down.
Once you’ve started sharing your test batches with friends and family, it’s only natural that they’ll keep asking you to remake it for them. And at this point, in order to keep up with demand, you might consider scaling up from one batch of dough at a time to two or three.
And just like baking cookies and finding the best recipe, you do the same thing for prep scale HPLC analysis.
It’s typical to start work at an analytical scale to synthesize new compounds in small test tubes, refining their reaction conditions producing only a few micrograms of material, testing and refining. With these smaller volumes, an analytical column can be used to separate out the target compound from any reactants, side products and contaminants. Once they crack the code and get the right recipe and are able to isolate the target compound of interest, the scientist might be asked to “scale up” the reaction to create more end product for further testing or as the final product itself.
As you can image, if the demand is great enough, it would not be efficient to separate and collect the purified compound using a small analytical column, just like if you were baking a large batch of cookie dough, a standard fork to mix and blend may not be as efficient as using an electric stand mixer. One would need to evaluate their hardware and realize that scaling up may require larger preparative HPLC columns.
Typically, when choosing an appropriate preparative HPLC column to scale up to, you not only want to consider the loadability of the new column, but you would want to maintain the same media between the analytical and prep column. Keeping the media chemistry, particle size, and quality consistent between columns minimizes variables which could dramatically alter the intended separation. For this reason, it is important to have a large portfolio of prep LC columns to choose from, so you can find the right chemistry, particle size, and hardware dimensions to meet your application needs. Luckily, with the recent launch of Thermo Scientific’s preparative HPLC columns portfolio, there are over 40 chemistries to choose from, optional XtendedLife hardware technology to improve column lifetime, and a variety of dimensions. And, if you can’t find one you need in our standard offering, just talk to your local sales rep about options including custom orders so you can get what you need.
To simplify and maintain the separation when transferring the method from the analytical column to the larger preparative column you can use our Preparative HPLC Method Transfer Tool to get new starting conditions to help maintain the resolution and separation you achieved on the analytical column.
Good luck on all of your scale up endeavors, in the kitchen and the lab!