Keeping an eye on the invisible traces

Micropollutants present a paradoxical problem for modern water management: although they often occur in very low concentrations, they can still cause ecological and health damage – for example, in the form of pharmaceutical residues, pesticides or industrial chemicals. The problem is that, precisely because the concentrations are so low, detection has so far often only been possible through complex, time-consuming and costly laboratory analysis. Within the Thuringian Water Innovation Cluster (ThWIC), the project “New Detection Methods for Micropollutants in Water (MIKA)” addresses precisely this gap: It aims to develop a label-free on-site method designed to make micropollutants in wastewater samples detectable more quickly. Regional partners, including Steinbeis Qualitätssicherung und Bildverarbeitung GmbH (SQB GmbH), are pooling expertise in photonics, data analysis and systems development to achieve this.

The ThWIC is funded as part of the nationwide Clusters4Future initiative of the Federal Ministry of Research, Technology and Space (BMFTR) and adopts a clearly interdisciplinary and transdisciplinary approach: new analytical technologies and purification processes are combined with perspectives from data science and the social sciences in order to develop water use in a holistic manner and translate the results into practical applications.

ThWIC as a bridge to application

The strategic dimension is noteworthy: ThWIC is set to receive funding from the BMFTR for up to nine years in order to transfer solutions for sustainable water use into industry. In a consortium of more than 40 partners, the ThWIC aims to bring cutting-edge technology to the regional economy whilst simultaneously strengthening ‘water awareness’ in society.

The MIKA project is situated within the innovation field “Water analysis” – one of the ThWIC’s four main focus areas. Here, technologies are being developed to detect chemical contamination in water not only more accurately but, above all, more practically – a key factor if monitoring is to become routine rather than the exception.

MIKA: A technological approach for rapid on-site detection

MIKA relies on a combination of plasmonic multiplex assays and fingerprint analysis to detect micropollutants in wastewater samples. The analysis is based on a precious metal nanoparticle array, in which the nanoparticles are arranged as spots and functionalised with aptamers. Aptamers are DNA-based receptors that bind to selected target molecules – in the case of MIKA, these include carbamazepine, diclofenac and benzotriazole as lead indicators of contamination in a water sample.

The binding initially provides indications of the class and properties of the contaminant. The crucial technical step is then the optical detection of these binding events in the visible spectral range – using a novel detector unit with spatially resolved imaging spectroscopy.

For additional specificity, MIKA supplements the optical signature with Surface-Enhanced Raman Spectroscopy (SERS). Here, the precious metal nanoparticles amplify the Raman signal – the result is a kind of molecular ‘fingerprint’ that makes the differentiation of chemical compounds more robust.

The intended range of applications extends beyond traditional water analysis: prospective fields of application also include medicine and environmental monitoring, as well as applications wherever high-resolution, rapid on-site detection offers genuine added value.

Successful transfer: from laboratory setup to a robust system

In this project, SQB GmbH is developing a high-precision detector unit with spatially resolved imaging spectroscopy, thereby addressing precisely the component that bridges the gap between biochemical binding (aptamer receptors) and data-driven evaluation in the overall MIKA system: optical detection as a module suitable for measurement and industrial use.

From a transfer perspective, it is particularly interesting that SQB is not only a research partner but also acts as a system integrator for image processing and camera systems. “This focus fits well with MIKA: once a detection principle works in principle, its implementation in robust, repeatable hardware and software chains determines whether a method can survive outside specialised laboratories,” summarises Managing Director Steffen Lübbecke.

Photonics, visualisation, design – and SQB as an engineering hub

Within the ThWIC environment, MIKA is a regional collaborative project involving the Leibniz Institute of Photonic Technology (Leibniz-IPHT), Friedrich Schiller University Jena (Computer Science – Visualisation and Exploratory Data Analysis) and design:lab weimar GmbH.

This combination is typical for technologies that require both “hard” measurement technology and usability: photonics provides optical depth, computer science delivers evaluation and visualisation logic, design ensures user interaction and application relevance – and SQB provides the engineering bridge to turn research setups into integrable measurement modules.

MIKA: More than a sensor project

MIKA addresses not only an analytical challenge but also a structural one: if water management is to become resilient, it requires higher-density measurability – both temporally and spatially. Laboratory analysis remains the gold standard, but it scales only to a limited extent in the day-to-day operations of plant management, water monitoring or short-term incident investigation.

The MIKA concept therefore combines three levers:

1. Selectivity at the receptor level (aptamers)
2. Information density on the sensor and signal side (imaging spectroscopy and SERS fingerprinting)
3. Decision-making speed on the data side

The role of SQB – the detection unit and its integration expertise – is not merely incidental, but a prerequisite for ensuring that the interplay of these factors can result in a manageable overall system.