Could you explain the significance of your article to the non-specialist?

The miniaturization of polymeric ion sensors necessitates the creation of a solid-state fabrication strategy, yet this approach normally provides poor quality polymeric sensors. For the very first time, this paper identified unequivocally a detrimental interfacial water layer in solid-state polymeric ion sensors, and this outcome has paved the way for the creation of a new generation of robust polymeric ion sensors.

What has motivated you to conduct this work?

Many authors have speculated about the existence of a detrimental water layer in polymeric ion sensors, but no single research group has provided direct structural evidence for this water layer. Our primary motivation in undertaking this research has been to develop a unique surface and interface analysis scheme, so as to enable the detection of water layers in solid contact polymeric ion sensors, and to employ this methodology in the evaluation of new strategies to combat the problems of water layers in solid contact polymeric ion sensors.

Where do you see this work developing in the future?

In further research, this surface and interface analysis scheme has been used in the development and evaluation of new fabrication strategies for robust solid contact polymeric ion sensors, and the authors are presently drafting a full paper on a new approach employing a water repellent ion sensing polymer film in combination with a hydrophobic conductive polymer underlayer or solid contact to ameliorate water uptake by the sensor and the concomitant undesirable water layer.

Are there any particular challenges facing future research in this area?

The spin casting of polymeric ion sensing films, as utilized in the present study, is impracticable for the commercial fabrication of miniaturized solid-state polymeric ion sensors. Furthermore, the use of "Big Science" characterization techniques such as neutron and x-ray reflectometry are inaccessible by industry. Accordingly, this research has also led to the development of an industrially practicable methodology to enable a realization of the commercial advantages of the new sensor fabrication technology. In this context, the researchers have developed a conventional electrodeposition method for the production of high integrity conductive polymer solid contacts, as well as a conventional electrochemical technique (i.e., electrochemical impedance spectroscopy) for the characterization of new solid-state polymeric ion sensors.