A Label-Free Immunosensor for Cryptosporidium Detection

Cryptosporidium is a waterborne protozoan parasite of significant public health concern, responsible for numerous outbreaks linked to contaminated drinking and recreational waters. Current detection methods are time-consuming, labour-intensive, and reliant on specialised laboratory techniques, limiting their suitability for rapid or on-site monitoring.

In this work, we present the development of a label-free electrochemical immunosensor for the detection of Cryptosporidium oocysts. The sensor is based on a biofunctionalised electrode platform and exploits electrochemical impedance spectroscopy to monitor changes at the electrode–electrolyte interface arising from antibody–oocyst binding. Target recognition leads to measurable changes in interfacial resistance and diffusion behaviour, enabling sensitive, reagent-free detection without the need for secondary labels or amplification steps.

The proposed sensing approach demonstrates the potential for rapid, sensitive, and scalable detection of Cryptosporidium, offering a promising alternative to conventional laboratory-based methods and a pathway towards real-time water quality monitoring.