Toward Development of a Label-Free Detection Technique for Microfluidic Fluorometric Peptide-Based Biosensor Systems

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Molecular Diagnostics

Background:

• Noncommunicable diseases (NCDs) pose a significant global health challenge, necessitating advanced diagnostic tools.
• Current diagnostic methods often lack the sensitivity and specificity required for effective treatment selection.
• Peptide aptamers offer a promising platform for targeted biomarker recognition in biosensing applications.

Purpose of the Study:

• To investigate a low-cost, label-free biosensor principle for detecting protein biomarkers using peptide aptamers.
• To develop a fluorometric detection system for enhanced sensitivity in biomarker quantification.
• To address challenges in stray light and background fluorescence for improved biosensor performance.

Main Methods:

• Design of peptide aptamers using in silico tools (Protein 3D software) with substituted aromatic amino acids.
• Selection of ZnS-based solid-state compounds as luminophores for fluorescence enhancement.
• Development of a microfluidic system with an optical detection setup utilizing thick film technology and an excitation-emission cascade.
• Testing with model proteins: troponin T, troponin I, and bovine serum albumin.

Main Results:

• Demonstrated a functional laboratory biosensor prototype capable of detecting target proteins.
• Successfully reduced background fluorescence and stray light through careful material selection and aptamer design.
• Validated the principle of re-emitting natural fluorescence of bound proteins into detectable longer-wavelength radiation.

Conclusions:

• The developed biosensor system shows potential for cost-effective, sensitive detection of NCD biomarkers.
• This approach offers a viable strategy for multiparametric combinatorial diagnostics.
• Further optimization could lead to practical applications in clinical diagnostics for noncommunicable diseases.