# Using Mean Kinetic Temperature Measurement to ensure safe and reliable pharmaceutical storage

## Storage and distribution for pharmaceuticals

Pharmaceuticals are a very big deal these days. R&D of new pharmaceuticals is very expensive, and requires extremely long lead times. If that wasn’t reason enough to be very careful of their materials, pharmaceutical companies are some of the most heavily regulated industries in the UK, as well they should be. Ensuring the quality and safety of their products, and the ever present drive to do so as efficiently and inexpensively as possible, means that every detail needs to be taken car of when storing or transporting these materials.

So proper care of pharmaceutical chemicals and products requires a strictly controlled environment – a lot more than just a refrigerated lorry. Many environmental conditions can affect pharmaceuticals, but temperature is generally the most important. Proper storage of pharmaceuticals and medicines must be done at an exact temperature range, and procedures must be in place to stabilise conditions quickly in the event of an electrical or mechanical failure, for example. You also need a way of tracking the conditions the stored materials have been exposed to, and for how long. That’s what MKT is.

## So how can you work out Mean Kinetic Temperature for products?

Mean Kinetic Temperature isn’t an actual measurement, per se. It is a way of expressing simply the effect any temperature changes will have had on any kind of perishable goods during storage or transit. If you know the MKT that a material has been stored at, you can make much more accurate predictions about its shelf life. Of course, like a lot of concepts that aim to be easy to use, it can be very complicated to arrive at.

MKT is expressed as a temperature. You arrive at this number by calculating the effect of any temperature changes that have occurred over time, and of course that particular material’s vulnerability to thermal stress. If the material had actually been stored at the MKT the whole time, it would be in just as good (or bad) a condition as it is in now.

For those of you with a taste for complicated maths, here are the equations for calculating MKT yourselves: (courtesy of Wikipedia.org)

$T_K=\cfrac{\frac{\Delta H}{R}}{-\ln \left ( \frac{{t_1}e^ \left ( \frac{-\Delta H}{RT_1}\right ) + {t_2}e^ \left ( \frac{-\Delta H}{RT_2}\right ) + \cdots + {t_n}e^ \left ( \frac{-\Delta H}{RT_n}\right )}{{t_1} + {t_2} + \cdots + {t_n}} \right )}$
For those of you playing along at home,
$T_K\,\!$ is the mean kinetic temperature in kelvins
$\Delta H\,\!$ is the activation energy (typically within 60–100 kJ·mol-1 for solids or liquids)
$R\,\!$ is the gas constant
$T_1\,\!$ to $T_n\,\!$ are the temperatures at each of the sample points in kelvins
$t_1\,\!$ to $t_n\,\!$ are time intervals at each of the sample points

This equation will not be on this week’s quiz, but you should be prepared to use it during the final exam.