Urease-coated polydopamine nanomotors as self-propelled biosensors for non-invasive diagnosis: detection of prostate...

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Analytical Chemistry

Background:

• Prostate cancer (PCa) diagnosis relies on early detection, yet current methods often lack non-invasiveness.
• Urinary biomarkers like microRNA-141 (miR-141) show promise for PCa detection.
• Development of sensitive and specific biosensing platforms is crucial for clinical application.

Purpose of the Study:

• To synthesize and characterize polydopamine/poly-L-lysine@urease (PDA/PLL@UR) nanomotors for detecting the PCa biomarker miR-141.
• To establish a novel nanomotor-based biosensing platform for rapid and non-invasive PCa diagnosis.
• To evaluate the diagnostic performance, sensitivity, and specificity of the developed nanomotor system.

Main Methods:

• Chemically synthesized PDA/PLL@UR nanomotors functionalized with ssDNA probes.
• Utilized urease-catalyzed urea decomposition for nanomotor self-propulsion and enhanced target recognition.
• Monitored fluorescence intensity changes and nanomotor velocity for miR-141 detection in urine samples.

Main Results:

• PDA/PLL@UR nanomotors exhibited self-propelled motion in urea solution, with velocity correlating to urea concentration.
• The system demonstrated strong linear correlations for fluorescence intensity and speed with high coefficients (R^2 = 0.98 and R^2 = 0.99).
• Achieved low limits of detection (LoD) of 7.5 pM for fluorescence and 170 pM for speed, with high specificity for miR-141 over other microRNAs.

Conclusions:

• The developed PDA/PLL@UR nanomotors provide a sensitive and specific platform for detecting urinary miR-141, a PCa biomarker.
• This nanomotor-based biosensing approach enables rapid, non-invasive, and potentially point-of-care diagnosis of prostate cancer.
• The study highlights the potential of mobile biosensing systems for future clinical diagnostic applications in oncology.