Enzyme Janus particle indicator for controlling the hygiene status of surfaces

IGF 19852 N

Hygiene quality management (QM)-systems are of great importance in hygienically demanding areas because hygiene requirements are constantly increasing. For analyzing quality of cleaning and disinfection measures determined by QM-systems, random controls are carried out routinely.

Currently, contact plates are used for sampling of surfaces. After sampling, contact plates must be incubated and analyzed by external microbiological laboratories. This requires a period of at least two days (determination of total germ count and hygienically relevant microorganisms) and results in high costs. Therefore, there is a strong need of innovative methods for determination of both, hygienically relevant microorganisms and total germ count on surfaces within a self-control.

Concerning this background, a new procedure for the detection of microorganisms on surfaces based on enzyme Janus particle indicators was developed within the scope of the research project. Enzyme Janus particle indicators consist of enzyme Janus particle complexes in which the enzyme activity is inhibited by functionalised Janus particles, a specific chromogenic substrate, and a hydrogel matrix.

The detection principle is based on the restoration of the enzyme activity. This occurs when the functionalized Janus particles bind to living microorganisms and the enzyme Janus particle complexes are eliminated. The chromogenic substrate is converted by active enzymes to form a colored cleavage product resulting in a visually perceptible color change of enzyme Janus particle indicator.

The project results provide the cleaning service providers with a method for the rapid determination of the hygienic condition of surfaces, which can be carried out cost-effectively within the framework of a self-check without the use of complicated evaluation systems. This enables any necessary corrective measures to be initiated immediately and hygiene safety to be optimised. By using the new process, cleaning service providers can drastically reduce the costs of hygiene controls.

The research report is available on request from FRT.

The IGF-pro­ject 19852 N of the re­search as­so­ci­a­tion Europäische Forschungs­ge­mein­schaft Reini­gungs- und Hy­gien­etech­nolo­gie e.V., Cam­pus Ficht­en­hain 11, 47807 Krefeld, was sup­port­ed with­in the fund­ing pro­gram „In­dus­trielle Gemein­schafts­forschung und -en­twick­lung (IGF)“ by the Fed­er­al Min­istry of Eco­nom­ic Af­fairs and Cli­mate Ac­tion due to a de­ci­sion of the Ger­man Par­lia­ment.