Rapid detection of microalgae cells based on upconversion nanoprobes.

Area of Science:

• Nanotechnology
• Environmental Science
• Analytical Chemistry

Background:

• Accurate quantification of microalgae is essential for ballast water treatment.
• Rapid detection methods for microalgae are needed for effective onboard analysis.

Purpose of the Study:

• To develop a rapid and effective method for microalgae concentration detection using upconversion nanoprobes (UCNPs).
• To enhance UCNP stability and functionality for aqueous environments.

Main Methods:

• Modification of hydrophobic NaYF4:Er3+,Tm3+ UCNPs with ligands (mPEG-COOH-5, mPEG-COOH-2, DGAS) to achieve hydrophilicity.
• Characterization of UCNP stability and functional groups using Fourier Transform Infrared Spectroscopy (FTIR).
• Detection of microalgae concentration via upconversion luminescence (UCL) quenching based on the inner filter effect.

Main Results:

• mPEG-COOH-5 modified UCNPs exhibited superior stability in aqueous solutions.
• Successful conversion of UCNPs to a hydrophilic state with enhanced biocompatibility.
• Established a quantifiable relationship between UCL intensity and microalgae concentration.

Conclusions:

• The developed UCNP-based method offers a rapid and accurate strategy for microalgae detection.
• This approach facilitates real-time, onboard monitoring crucial for ballast water management.
• The findings present a promising advancement in sensing technologies for environmental applications.