An ultrasensitive platform for PCB77 detection: New strategy for liquid crystal-based aptasensor fabrication

Area of Science:

• Environmental Science
• Analytical Chemistry
• Biotechnology

Background:

• Polychlorinated biphenyls (PCBs) are persistent bioaccumulative toxicants impacting food safety and environmental health.
• Traditional PCB detection methods are slow and unsuitable for rapid monitoring.
• Biosensor technology presents a potential solution for efficient pollutant detection.

Purpose of the Study:

• To develop a novel, rapid, and label-free biosensor for detecting PCB77.
• To utilize a liquid crystal (LC) aptasensing platform for enhanced sensitivity and selectivity.
• To demonstrate the applicability of the biosensor in real-world environmental and food samples.

Main Methods:

• A liquid crystal (LC)-based aptasensing platform was designed.
• A triple-helix molecular conformational switch mechanism was employed for target-mediated duplex formation.
• Optical signal changes (dark to bright) were used for label-free detection of PCB77.

Main Results:

• The developed LC-aptasensor achieved a limit of quantification of 1.5 × 10⁻⁵ μg/L for PCB77.
• The sensor demonstrated comparable selectivity for PCB77 detection.
• Successful detection of PCB77 was achieved in tap water, environmental water, and milk samples.

Conclusions:

• The novel LC-aptasensor provides a promising strategy for rapid, label-free, and portable detection of PCB77.
• This approach has potential for detecting various targets without aptamer sequence length limitations.
• The developed biosensor can contribute to improved environmental monitoring and food safety assessments.