There are many ways to measure accuracy.
GlycoSpot’s assay is very reproducible because we have a controlled manufacturing process. An equal amount of the substrate is placed in each of our reaction tubes with which the protease will act on. The color generated in our assay is then used for measuring with the new SIRIUS platform. Our scientists do a calibration of each batch to check that it passes quality control. They test a range of enzyme concentrations, from low to high. The range depends on which application, enzyme, product, manufacturer, and concentration our customers are using.
As a result, we can implement a correction for minor batch variation. This is done through a QR code within the app. By using the complete SIRIUS solution, this QR code will pull batch specific calibration models for each batch of substrates to ensure an even higher accuracy.
Factors that can influence accuracy.
The assay itself is very reproducible. Most of the variation that we have seen through working with different customers comes from the sample itself. Enzymes are biological molecules, and they are quite flexible in how they behave. So when you refer to enzyme activity, there are several things that are commonly thought off that influence its activity.
Enzyme activity can be influenced by:
Temperature. We control the temperature by providing a shaking incubator. The ability to reproduce and maintain the temperature of the assay for the specified amount of time, increases the chances of an accurate reproducibility.
pH levels. The pH is controlled through our assay buffer’s composition. It is optimized for alkaline proteases commonly used in industrial cleaning applications: Harsh chemicals can impact enzyme activity that our assay cannot control. But we can measure those effects. Our assay is also compatible with other pH, for example measuring activity and concentration of neutral proteases. You are welcome to use your preferred buffer or sample matrix.
The quality of water. The water used in the actual cleaning process – demineralized, deionized, soft and hard water can have a big impact on enzyme activity. As with pH and other matrix effects, our assay can provide information to guide optimization of your process.
Our CIP assay is a tool that the customer can use to see how enzyme activity increases or decreases under different conditions.
In one example, there is a process with several steps and different chemical compositions in the cleaning process . In the first step, the chemistry is optimized for the enzyme, so there is high activity.
The second step has harsh chemistry with a negative impact on enzyme performance. In the final step, the conditions are mild and support high enzyme activity again.
This results in three different calibration lines that could be made for the three different chemical matrices. For each matrix, we compare how far from the predicted calibration line each individual measurement is. For half of the measurements, the known enzyme dose is within 5% from the predicted line. Greater than 75% of the measurements are within 10% of the known enzyme dose.
Therefore, a single measurement using our assay can accurately estimate the actual enzyme concentration. If two or three measurements per sample are made, the average value is typically within 5% of the true dose.
See our test kits here.