Aptamer-functionalized capacitive biosensors

Area of Science:

• Biosensing
• Biotechnology
• Analytical Chemistry

Background:

• Aptamers are increasingly used as recognition elements in label-free biosensors.
• Capacitive sensors, though popular in other fields, have limited but growing application with aptamers.
• Physiologically relevant sensitivity and a clear understanding of capacitance changes upon target capture are lacking.

Purpose of the Study:

• To review the current state of aptamer-based capacitive biosensors for small molecules, proteins, and cells.
• To critically analyze conflicting hypotheses regarding how aptamer-target binding affects capacitance.
• To provide recommendations for developing aptasensors for clinical settings.

Main Methods:

• Literature review of aptamer-based capacitive biosensing.
• Analysis of proposed mechanisms for capacitance changes upon aptamer-target interaction.
• Assessment of sensing capabilities for small molecules, proteins, and cells.

Main Results:

• The field shows growing use of aptamers with capacitive sensors for diverse targets.
• Conflicting mechanistic explanations exist for capacitance changes during target capture.
• Limited studies demonstrate physiologically relevant sensitivity under laboratory conditions.

Conclusions:

• Further research is needed to elucidate individual aptamer-target interactions and physical mechanisms of capacitance change.
• Standardized methodologies and a focus on clinical applicability are crucial for advancing aptasensor development.
• This review provides recommendations for best practices in aptasensor development, particularly for clinical applications.