Paramagnetic nanoparticles as a platform for FRET-based sarcosine picomolar detection

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Oncology

Background:

• Prostate carcinoma detection relies on accurate biomarkers.
• Sarcosine is a potential biomarker for prostate cancer, but sensitive detection methods are needed.
• Förster resonance energy transfer (FRET) offers a sensitive detection mechanism.

Purpose of the Study:

• To develop an ultrasensitive and specific biosensing system for sarcosine detection.
• To utilize FRET principles for quantifying sarcosine as a prostate cancer biomarker.
• To validate the biosensor's performance in cell lines and patient samples.

Main Methods:

• Immobilization of anti-sarcosine antibodies on paramagnetic nanoparticles.
• Assembly of a sandwich construct upon sarcosine binding, enabling FRET.
• Detection via spectral overlap between gold-functionalized green fluorescent protein and antibody-conjugated quantum dots.

Main Results:

• The FRET biosensor demonstrated high sensitivity with a detection limit as low as 50 pM.
• A linear dynamic range from 5 to 50 nM was established for sarcosine quantification.
• Successful quantification of sarcosine was achieved in prostate cancer cell lines and patient urine samples.

Conclusions:

• The developed FRET biosensor is a sensitive and specific tool for prostate cancer biomarker detection.
• This system shows promise for clinical application in diagnosing prostate adenocarcinoma.
• The biosensor's ability to detect sarcosine in complex biological matrices validates its potential utility.