Editorial Article: 10 Tips for Optimizing your Life Sciences Assay

We all know that biology can be somewhat uncooperative when it comes to working on the bench. Perhaps it looked like your proteins didn’t feel like binding that day? Maybe your bacteria apparently didn’t like the temperature of the incubator over the weekend? Or it seemed as though your enzyme wanted to work a little slower on a Friday afternoon?

Nevertheless, there are fundamental things to remember whenever you are planning, preparing, or performing an assay.

1.Optimize your temperature

Most things in the life science laboratory have an optimal temperature, be it a yeast, bacteria, enzyme or even a simple protein string. Getting your temperature profiling right (especially if your protocol involves moving between different temperature environments) can have a marked effect on your results. Try tweaking the settings on your incubator, or investing in a more accurate piece of lab kit, and see if your yields improve.

2.Optimize your mixing

Another commonly performed step in a range of assays is mixing – be that a gentle swirling, or an aggressive bead-milling stage. At either end of the spectrum, it is important to ensure that your sample is getting exactly the treatment it deserves time after time.

This is where picking the right equipment can really come into play – do you need a mixer that can just move the sample at max speed, or do you need something more controlled? Equally, can the mixer that you’ve decided to use actually perform the way you need it to – there’s no point opting for a shaker with a set speed of 2000rpm, when your assay would really benefit from going to 2500 or even 3000 with vortex motion.

3.Keep an eye on the time

All life science assays have one thing in common – timing is everything. If the protocol says to mix for five minutes, get the timer on the bench and make sure you go for the full five minutes – no more, and no less. If you need to incubate your samples for an hour, get them into the right environment as soon as possible, and let them have their full time.

A few minutes difference in time can make a huge difference in the results. Equally make sure that the practice is as standardized as possible between you and your colleagues – analyzing results where one batch had incubated for 60 minutes, another for 65 and another for 68 is just a waste of everyone’s most precious commodity – time.

4.Don’t move it if you don’t have to

With most complex assays, the samples will find themselves on a whistle-stop tour of your laboratory, moving from bench to bench, instrument to instrument, and hand to hand as needed. Next time you’re at work, count the number of times you have to pick up and move that plate, tube or other vessel because you need to change the temperature environment, or it needs to come out of the incubator to be mixed and go back in again – you’ll be surprised how much involvement you can have.

There are now a growing range of instruments that try to reduce steps like this - the fewer steps in your method, the lower the variability in your results.

5.Are you using the best consumables?

There are a range of laboratory consumables, be they microplates, petri dishes or microcentrifuge tubes from an ever-growing range of manufacturers and distributors. They might all look the same, but are the ones in your lab cupboard really the best ones for you? Whilst there is a time and place for basic low-cost items, if you’re working on an assay that uses high-cost chemicals or reagents that is time consuming and sensitive to variation, it pays to use a higher grade of consumable that is going to give you the same result every time.

Check the tech specs for things like sterility, binding properties and whether or not your samples are at risk of coming into contact with leachates, or in the case of aggressive samples, in danger of eating their way out of the container!

6.Use the best reagents you can

Equally important to your plastics are your reagents. This should be basic knowledge for anyone in the laboratory, but getting the right grade of reagent is crucial. Even water, the humblest of molecules, has a range of grades available. Do you just want standard sterilized tap water? Deionized? HPLC grade? The possibilities (and the price tags) are endless. Apply this same logic to everything else you use – are you getting your more expensive reagents from a reputable supplier who can give you a certificate of purity or conformance, or are you ordering from eBay, no questions asked? Match the grade of reagent to the requirements of the assay, and go from there.

7.Storage conditions

Everything in your workplace will have an ideal storage condition – certain plastics for example can degrade if kept exposed to sunlight, reagents may need to be kept chilled or frozen, or compounds might need to be heated up before use. Check that you have optimized your storage conditions wherever possible – even considering going the extra mile and investing in some temperature control and monitoring. Just because the fridge you are using says it is cold enough doesn’t mean that it is – a simple temperature probe immersed in glycerol can give you a more realistic reading and help ensure that those vital reagents work the same way every time.

8.Are you performing well?

So far in this list we’ve focused on the equipment, the reagents, the consumables, and anything else that might add variability into the laboratory – but we’ve forgotten the one critical factor in all of this. The part that makes sure the samples end up in the right places, that makes sure all the correct data is recorded – that’s right, we’re talking about you! Are you working as well as you should be?

Now we’re not suggesting you go get a physical, but it is worth looking at your workspace, and thinking for a moment, what do you hate the most? Are you using one piece of kit on one side of the bench, and then trekking to the other end of the laboratory for the other? Do you have enough bench space or are you working with everything piled on top of each other? If so, can you streamline your workspace?

9.Think outside the box

Never discount anything – if at first your assay doesn’t perform the way you thought it would, go back to basics and examine your original hypothesis. From there, work methodically from start to finish, checking everything that might have led to a change (including the 8 points that came before this one!).

Perhaps something simple but unobvious such as a mislabeled jar or an out-of-date reagent is to blame? There could be a problem with the workspace itself – if you have a light-sensitive reaction for example, are there any sources of natural light near your bench that could have contributed? Think outside the box, and re-examine everything.

10.Be patient

The life sciences can be some of the most dynamic of all the disciplines, but can equally be one of the most frustrating. Everything happens for a reason, and if something doesn’t go the way you hoped/thought/expected it to go, don’t lose heart.

Keep calm, and carry on. 

To view the infographic, click here.