Sensing Cellular Metabolic Activity via a Molecular-Controlled Semiconductor Resistor

Area of Science:

• Semiconductor device physics
• Biosensor technology
• Cellular biology

Background:

• Molecular-controlled semiconductor resistor (MOCSER) devices are sensitive to surface potential variations.
• Gallium arsenide (GaAs) offers high electron mobility for biosensor development but suffers from instability and toxicity.
• Overcoming GaAs instability is crucial for effective biosensor applications.

Purpose of the Study:

• To develop an electronic biosensor for real-time, label-free monitoring of cellular metabolic activity.
• To address the chemical instability and toxicity issues of GaAs in biosensor applications.
• To investigate the sensitivity of the MOCSER device to cellular metabolic changes.

Main Methods:

• Developed a MOCSER device based on an AlGaAs/GaAs structure.
• Applied polymerized (3-mercaptopropyl)-trimethoxysilane (MPTMS) and (3-aminopropyl)-trimethoxysilane (APTMS) as protective and biocompatible surface layers.
• Cultured HeLa cells directly on the MOCSER device for metabolic activity monitoring.

Main Results:

• Successfully cultured HeLa cells on the MOCSER devices, demonstrating stability and sensitivity.
• The MOCSER device's sensitivity is attributed to sensing extracellular acidification.
• Optimal sensitivity was observed with partial cellular coverage, with full coverage reducing conductivity due to cell membrane potentials.

Conclusions:

• The coated MOCSER device provides a stable and sensitive platform for biosensing.
• The device enables real-time, label-free monitoring of cellular metabolic activity and viability.
• Further application of this biosensor for continuous monitoring of cellular health is proposed.