Upconversion luminescence-based aptasensor for the detection of thyroid-stimulating hormone in serum

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Nanotechnology

Background:

• Thyroid-stimulating hormone (TSH) is vital for physiological and pathological processes.
• Early and sensitive TSH detection is critical for diagnosing and preventing thyroid diseases.
• Existing detection methods may lack sensitivity or be complicated for clinical use.

Purpose of the Study:

• To develop a simple, wash-free biological aptasensor for sensitive TSH detection.
• To utilize luminescence resonance energy transfer (LRET) between upconversion nanoparticles (UCNPs) and tetramethylrhodamine (TAMRA).
• To enable quantitative analysis of TSH activity in serum samples.

Main Methods:

• Fabrication of an aptasensor using UCNPs as LRET donors and TAMRA as receptors, modified with specific aptamers.
• Utilizing the LRET mechanism triggered by TSH binding, leading to a change in upconversion luminescence (UCL) intensity at 545nm.
• Quantifying TSH levels by measuring the change in UCL intensity (I545nm) upon TSH presence.

Main Results:

• The aptasensor demonstrated a detection dynamic range of 0.1-5.0 mIU·L⁻¹ and a limit of detection of 0.065 mIU·L⁻¹.
• The system effectively minimized background interference from complex biological environments.
• The aptasensor exhibited high specificity due to the aptamers' recognition capabilities.

Conclusions:

• The developed UCNP-based LRET aptasensor offers high sensitivity, selectivity, and operational simplicity for TSH detection.
• This wash-free assay is a promising candidate for clinical TSH determination and early thyroid disease diagnosis.
• The aptasensor provides a reliable method for quantitative TSH analysis in serum.