Implementing Silicon Nanoribbon Field-Effect Transistors as Arrays for Multiple Ion Detection

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Chemical Sensing

Background:

• Ionic gradients are vital for human physiological processes, including cellular metabolism and neural activity.
• Current methods for ion monitoring often lack cost-effectiveness and label-free capabilities.
• Silicon nanoribbon field-effect transistors (SiNR FETs) offer a promising platform for developing integrated, low-cost biosensors.

Purpose of the Study:

• To develop a single sensor chip capable of simultaneously detecting sodium (Na+) and fluoride (F-) ions.
• To leverage SiNR FETs for label-free, real-time monitoring of key physiological ions.
• To establish a foundation for multifunctional chemical sensing platforms.

Main Methods:

• Fabrication of dense arrays of gold-coated SiNR FETs on a single chip.
• Utilizing a microfluidic system with individual channels for surface functionalization.
• Immobilization of specific ion receptors onto SiNR surfaces using self-assembled monolayers.
• Implementation of a differential sensing setup with active and control (bare gold) nanoribbons.

Main Results:

• Demonstrated the feasibility of simultaneous Na+ and F- ion detection using the developed SiNR FET sensor chip.
• Successfully functionalized nanoribbons with distinct ion receptors for selective ion binding.
• Established a method to compensate for non-specific signal variations by comparing active and control sensors.

Conclusions:

• The developed SiNR FET sensor chip provides a basis for simultaneous, label-free detection of sodium and fluoride ions.
• This technology enables the development of advanced, multifunctional chemical sensing platforms for physiological monitoring.
• The differential sensing approach enhances accuracy by mitigating background electrolyte effects.