All-integrated and highly sensitive paper based device with sample treatment platform for Cd2+ immunodetection in...

Area of Science:

• Analytical Chemistry
• Environmental Science
• Biosensing

Background:

• Developing integrated systems for clinical, environmental, or industrial analysis is challenging.
• Existing methods for cadmium detection often require extensive sample pretreatment.

Purpose of the Study:

• To present a novel, integrated paper-based immunosensing system for cadmium (Cd2+) detection.
• To simplify the detection process by combining sample treatment and analyte detection in a lateral flow format.

Main Methods:

• Utilized a competitive immunoassay on a paper strip with a Cd-EDTA-BSA-AuNP conjugate and a Cd-EDTA complex.
• Incorporated an additional conjugation pad for in-situ Cd2+ complexation with EDTA and interference masking using ovalbumin (OVA).
• Validated the system using drinking water samples and compared results with Inductively Coupled Plasma Emission Spectroscopy (ICPES).

Main Results:

• Achieved detection and quantification limits of 0.1 and 0.4 ppb for Cd2+, respectively.
• Demonstrated high accuracy with sample recoveries ranging from 95% to 105%.
• Exhibited excellent intermediate precision with a coefficient of variation below 10%.

Conclusions:

• The developed paper-based immunosensing system offers a simple, rapid, and sensitive method for Cd2+ detection.
• This integrated platform eliminates the need for sample pretreatment, making it suitable for on-site environmental monitoring.
• The system's performance is comparable to established methods like ICPES, with superior sensitivity for paper-based sensors.