Paper-Based Analytical Device Coated with a Fluorescent Polymer for the Visual Detection of Biothiols

Area of Science:

• Analytical Chemistry
• Biochemistry
• Environmental Science

Background:

• Redox balance and oxidative stress are critical in biological and environmental systems.
• Thiol-containing compounds (biothiols) play a vital role in maintaining this balance.
• Accurate detection of biothiols is essential for understanding these processes.

Purpose of the Study:

• To develop a rapid, quantitative, and user-friendly paper-based analytical device (PAD) for biothiol detection.
• To optimize the PAD for enhanced dynamic range and sensitivity.
• To validate the PAD's performance in complex biological and environmental samples.

Main Methods:

• Development of a PAD utilizing a cysteine-specific fluorescent probe.
• Optimization of assay conditions and reaction kinetics for cysteine (Cys) detection.
• Incorporation of cystine for broader biothiol quantification.
• Validation against conventional spectroscopic methods (e.g., 5,5'-dithiobis(2-nitrobenzoic acid)).

Main Results:

• The PAD successfully detected and quantified biothiols in aqueous solutions and cell homogenates.
• Optimized conditions expanded the dynamic range and lowered the detection limit for Cys.
• High reproducibility and sensitivity were achieved for various biothiols.
• PAD results showed strong correlation with established spectroscopic methods.

Conclusions:

• The developed PAD provides a cost-effective, portable, and user-friendly solution for on-site and real-time redox monitoring.
• This technology has significant potential for applications in biomedical research, diagnostics, and environmental monitoring.
• The PAD offers a versatile tool for assessing oxidative stress and redox balance.