Culture Shock: How Absorbance 96 Enables OD600 Measurement in Anaerobic Conditions

The fate of a microbiologist, measuring a slightly yellow, or slightly less-yellow solution is the exciting key to many experiments. Often, getting the answer to simple questions is more complicated than it should be:  how many cells are present, which growth phase are they in, when can I harvest, when can I go home? Aside from walking to wherever there may (or may not) be a working photometer, the main challenge is getting reliable measurements in the environment you need them. This can be particularly challenging when considering the most difficult of bacteria to culture: the anaerobes. 

Measurements in limited space are challenging

As a colleague of mine once put it, “those little bastards” are notoriously hard to cultivate. A major step on the way to ensuring the anaerobes can grow in their preferred environment is anaerobic chambers. These chambers allow for tight control of the anaerobic environment, resulting in specific atmospheric conditions in humidity, temperature, and gas composition. The problem with monitoring culture growth within such chambers, however, is that space is highly restricted, and the use of most microplate readers or photometers for OD600 measurements is precluded by their prohibitive size. In addition, due to the sometimes-extreme environments created inside the chamber, standard devices can be corroded or otherwise damaged by harsh conditions. 

Stunningly easy workflow for OD600 measurements

So, what’s the solution, you ask? Imagine if there were instruments that were just as capable as their counterparts, but 1/10th the size. Imagine these instruments could fit through the airlock of an anaerobic chamber: too good to be true, right? Wrong. When it comes to tight spaces, the Absorbance 96 microplate reader is up to the challenge. Aside from offering stunningly easy workflows for benchtop monitoring of bacterial growth via OD600 measurements, the footprint of the Absorbance 96 is only slightly larger than a 96-well microplate, meaning it fits through the airlock of any anaerobic workstation. It further addresses the environmental challenges posed by being robust to high humidity and temperature conditions. Not to forget, it is as robust as other microplate readers for measuring OD values, examined in a comparative study. 

Using professional shakers for optimal results

After overcoming the environmental challenges, the issue of sedimentation remains. To prevent the bacteria from loitering, it’s useful to shake the living daylights out of them. While some microplate readers offer built-in shakers, these are often a pale imitation of real shakers, not offering sufficient RPM to achieve the desired effect (absolute microbial bedlam, i.e. the AMB state). Since the Absorbance 96 is so small, it can be used with an adapter to be incorporated onto any SBS-format shaker – a shaker being a piece of lab kit that you probably already have and don’t need to pay extra for. 

In summary

Although there are barriers to cultivating the incredibly diverse range of bacteria found in the gut microbiome and other anaerobic bacteria, they are being tackled by companies innovating in environmental control and hardware miniaturization. The compact Absorbance 96 fits through any airlock and provides the perfect tool to study your bacterium in its own unique environment.