Easy-to-use and battery-free detection of selected hazardous materials and chiral compounds via cholesteric polymer sensors

The proposed project aims to design and develop easy-to-use, battery-free and low-cost flexible cholesteric polymer sensors (ChPS) that change color upon contact with specific hazardous substances or one of the enantiomers of a chiral compound. These sensors, based on organic materials, are characterized by a helical molecular arrangement that enables the selective reflection of electromagnetic waves at wavelengths determined by the helical pitch. By precisely tailoring the chemical composition and fabrication conditions, we seek to engineer flexible, battery-free polymer films capable of selective and sensitive detection of specific hazardous substances, including toxic metal cations (e.g., As³⁺) and organophosphorus compounds, as well as differentiating between enantiomers of chiral molecules.

The indiscriminate exploitation of natural resources has led to the widespread emission of toxic metals such as arsenic, lead, mercury, and cadmium, which severely contaminate soil and groundwater, posing serious ecological and health risks. Among these, arsenic contamination, especially from water-soluble sodium meta-arsenite (NaAsO₂), is of particular concern due to its extensive use in agriculture and industry. Numerous studies have confirmed its cytotoxic and genotoxic effects on humans and animals. Simultaneously, the enantioselective detection of chiral compounds is of critical importance across pharmaceuticals, agrochemicals, and food safety. Enantiomers often exhibit markedly different biological activities, making their discrimination vital for efficacy, safety, and regulatory compliance. In pharmaceutical production, for instance, the presence of even trace amounts of enantiomeric impurities (below 1%) can undermine drug safety and performance. Likewise, trace-level detection of chiral additives, such as amino acids in food, and metabolic intermediates in biotechnological applications, is essential. Detection of organophosphorus compounds is equally critical, as these substances—used extensively in fertilizers, herbicides, and pesticides—also include highly toxic warfare agents (TWAs), also known as nerve agents. Given the ongoing geopolitical instability and increasing threat of chemical warfare, there is a growing need for portable, field-deployable, and user-friendly sensors that can reliably detect such compounds.

Current analytical techniques for detecting chiral molecules and toxic metal ions—such as high-performance liquid chromatography (HPLC), gas chromatography (GC), ultraviolet and vibrational circular dichroism (ECD, VCD), and NMR with chiral derivatizing agents, as well as atomic absorption spectroscopy and inductively coupled plasma mass spectrometry—require sophisticated, expensive instrumentation, laborious sample preparation, and operation by trained staff in specialized laboratories. In the case of toxic warfare agents (TWAs), optical indicators have been used, but they generally suffer from low sensitivity and selectivity and are often limited to liquid-phase detection.

In contrast, the proposed ChPS-based materials offer several critical advantages over these conventional methods. These polymer films are inexpensive, battery-free, easy to use without specialized training, and can be applied directly in the field at the site of analyte presence. Their operation principle is based on the analyte-induced modulation of the cholesteric helical pitch, resulting in a visually detectable color change in the film. To achieve stereoselectivity, molecular imprinting techniques will be employed to introduce enantio-specific cavities into the ChPS matrix. High selectivity toward specific metal cations (e.g., As³⁺) will be accomplished through the incorporation of appropriate molecular linkers, such as L-cysteine. Furthermore, sensors sensitivity will be enhanced by molecular modification of ChPS components to include stronger hydrogen-bond acidic polymers.

This approach promises the development of novel, scalable, and practical sensing materials tailored for rapid detection of hazardous substances and chiral discrimination, with wide applicability in environmental monitoring, public safety, pharmaceuticals, and chemical warfare defense.

We are seeking:

•        Application/testing partners (e.g., industrial or defense sectors) capable of validating the performance of developed cholesteric polymer sensors in real-world conditions (e.g., environmental monitoring, pharmaceuticals, or chemical threat detection).

•        Manufacturing partners with experience in polymer processing, scale-up, and device integration for sensor production and commercialization.

From our side, we provide expertise in material synthesis, structural design, and fundamental research, including optical, chemical, and molecular characterization of self-organized cholesteric systems.