Equilibrating silica flash chromatography columns is something I always do. There are chemists who see this as an unnecessary, time-and-solvent-wasting step. However, because getting consistent, predictable results is a priority for me, I equilibrate to remove the variability that can be caused by heat generated as solvent initially contacts the silica. Consistency is really important when running flash column chromatography because re-runs are time consuming and may put your compound at risk.
Most flash column manufacturers now offer “high performance” flash chromatography columns with the promise of higher loading, increased purity, and even reduced solvent consumption. Working for Biotage, I have made those valid claims for our products as well.
This is an interesting question that does not have a straightforward answer. In fact, there are many materials that are potentially useful sorbents for dry loading crude mixtures. Some of the more popular are silica, diatomaceous earth (e.g. ISOLUTE® HM-N, Celite®), alumina, and Florisil®. The sorbent choice can influence your purification results because each of the available media have different chemistry and capacity. In most cases, sample/sorbent reactivity really is not a major concern, though it can occur. What is important is the sorbent’s capacity to adsorb/absorb all of your sample and the ratio of your crude sample to the amount of dry load sorbent.
Dry loading crude samples for flash purification typically works better than liquid loading, especially for challenging purifications. In this post, I discuss how the ratio of crude sample to dry load sorbent impacts purification performance.
When it comes time to purify your reaction mixture or natural product extract, you have a choice to make. Should you simply load your dissolved sample onto your flash column or take the extra step to adsorb your mix onto a sorbent and dry it before loading? The choice can have a major impact on your results.
In this post, I will share results of work I conducted in my lab, comparing liquid and dry loading a reaction mixture that containing eight major components.
Sfär Stands for Spherical, Biotage® Stands for Quality
Biotage developed and introduced pre-packed columns for flash purification in 1994. Today our broad selection of columns enables professionals to choose the solution which best suits their purification needs.
Sfär is the Swedish word for "sphere", and the name of our columns reflects the fact that we have made spherical silica a standard due to its higher surface area and higher loading capacity. Reliable and flexible, Biotage® Sfär columns deliver larger loading capacities, tighter elution bands and purer fractions than traditional flash columns.
Biotage® Sfär is a complete portfolio of flash columns, available in a large variety of sizes from 5g to 350 g and in a range of media types, so you can purify milligrams to multi-grams of your valuable compounds quickly and easily.
New drug substances, the result of more than a decade of pharmaceutical research and development, have revolutionized society by saving lives, increasing life-spans, reducing suffering, avoiding surgery, and shortening hospital stays. New breakthroughs in the treatment of non-communicable diseases mean that drug substances are in a constant state of high demand, making the pharmaceutical industry one of the most innovative of industries on the globe. Why then, do so few drugs come to market? It turns out that a key factor is providing drug discovery chemists with tools such as automated flash chromatography to ensure that they can be confident in delivering target compounds in a timely fashion.
Isn’t amazing chemistry what you want to do every day? Don’t you strive for white crystalline final products? But things get in the way, such as other priorities, endless emails and frequent interruptions to your synthetic flow. Not to mention the challenges of designing new synthetic strategies, creating what could be the world’s most impactful new molecular entity. Finding the right reaction, the right reagents. Finding a way to get around yet another dead end. But those challenges are why you got into chemistry in the first place, right? After all, if it was easy, anyone could do it and you’re not just anyone. So let’s look at a few things that can put the fun back into chemistry.