Periodic Reporting for period 3 - ConquerIons (Conquering a New Paradigm for Addressing Ion Detection in Real Scenarios)
Période du rapport: 2022-10-01 au 2024-03-31
1) Electrochemical and optical ion sensors whose architecture fundaments on two main interconnected elements: the redox mediator and the nanomembrane. For the redox mediator, a series of lipophilic metallic compounds and conducting polymers have been synthetized and investigated, with the main outcomes highlighting the suitability of a newly synthetized osmium-based compound. For the nanomembrane, the project has researched on materials, composition and the modelling of the working mechanism, which is essentially based on a series of interconnected charge-transfer processes. The main results demonstrated the robust and reversible detection of different ions, with unusually wide analytical range of response.
2) The project has investigated the electrochemical protocol to interrogate the sensors and the corresponding electrochemical and optical readouts. The improvement of the limit of detection has been demonstrated.
3) Spectroelectrochemistry has been proved as an excellent vehicle for both mechanistical studies and better exploitation of the analytical performance of the sensors.
4) The project is now researching on the integration of thin-layer samples together with the mediator-nanomembrane tandem towards calibration-free sensors.
5) The mediator-nanomembrane tandem has been preliminarily translated to the nanoparticle format, being characterized under light-driven conditions.
6) Some cases of exploitation of the ion sensors at the laboratory scale have been achieved. Potassium, sodium, silver, copper, lead, chloride and phosphate ions have been determined in certain artificial clinical samples, as well as commercially available products and environmental waters.
7) It has been discovered that the nanomembranes can be implemented in the format of nanosensors for extra- and intra-cellular measurements, and for the selective ion capturing in complex matrix samples to reduce influence of ionic interferences in the electrochemical readout. In the case of the redox mediator, it has been found that certain conducting polymers can be utilized as solid acidifiers of samples, since their structures include exchangeable hydrogen ions. This capability has been implemented in sensor-actuator systems for the imaging of environmental processes.