Multifunctional dopamine-modified conjugated polymer nanoparticles for ultrasensitive immunoassays

Area of Science:

• Biotechnology
• Nanotechnology
• Analytical Chemistry

Background:

• Ultrasensitive immunoassays are crucial for early disease diagnosis and treatment.
• Integrating amplification strategies with sensitive probes enhances immunoassay performance.

Purpose of the Study:

• To develop a multifunctional and integrated probe for ultrasensitive immunoassays.
• To leverage dopamine and fluorescent conjugated polymer nanoparticles for improved detection.

Main Methods:

• A one-step nanoprecipitation method was used to prepare dopamine-modified conjugated polymer nanoparticles (DA-CPNs).
• DA-CPNs were deposited onto proteins catalyzed by horseradish peroxidase (HRP) in a sandwich immunoassay.
• Self-polymerization of DA-CPNs amplified the detection signal.

Main Results:

• The DA-CPN probe demonstrated rapid deposition and signal amplification through self-polymerization.
• Conjugated polymer nanoparticles (CPNs) exhibited high fluorescence brightness and photobleaching resistance.
• The method achieved a wide linear range (five orders of magnitude) and exceptional sensitivity (0.39 fg/mL detection limit) for Carcinoma Embryonic Antigen (CEA).

Conclusions:

• The developed DA-CPN probe offers a versatile platform for ultrasensitive immunoassays.
• This approach simplifies experimental procedures while enhancing sensitivity.
• The DA-CPN probe shows significant promise for in vitro diagnostics and early disease detection.