Photon-upconversion nanoparticles as a background-free label in immunosensing and bioimaging

FARKA, Zdeněk, Matthias Jürgen MICKERT, Antonín HLAVÁČEK, Hans-Heiner GORRIS and Petr SKLÁDAL. Photon-upconversion nanoparticles as a background-free label in immunosensing and bioimaging. In 31st Anniversary World Congress on Biosensors. 2021.

Basic information

• Original name: Photon-upconversion nanoparticles as a background-free label in immunosensing and bioimaging
• Authors: FARKA, Zdeněk, Matthias Jürgen MICKERT, Antonín HLAVÁČEK, Hans-Heiner GORRIS and Petr SKLÁDAL.
• Edition: 31st Anniversary World Congress on Biosensors, 2021.

Other information

• Original language: English
• Type of outcome: Conference abstract
• Field of Study: 10406 Analytical chemistry
• Country of publisher: Czech Republic
• Confidentiality degree: is not subject to a state or trade secret
• Organization unit: Faculty of Science
• Tags: International impact

Abstract

Fluorescence-based detection is very popular readout method in immunosensing and cell imaging. However, it is limited by autofluorescence and light scattering of the surrounding matrix. This optical background can be elegantly avoided by using photon-upconversion nanoparticles (UCNPs), which emit shorter-wavelength light under near-infrared excitation (anti-Stokes emission). Bioconjugates of UCNPs can be used as a background-free luminescent label in upconversion-linked immunosensing. We have synthesized conjugates of UCNPs with streptavidin based on copper-free click chemistry and coating of the UCNPs by bovine serum albumin, which reduces the level of non-specific binding. The conjugates were employed in sandwich detection of bacterium Melissococcus plutonius, the causative agent of honeybee disease of European foulbrood. The assay provided a limit of detection of 340 CFU/mL, which is 400 times better than conventional ELISA. The practical applicability was verified by the analysis of real samples of honeybees, larvae and bottom hive debris. The conjugates of UCNPs can also serve as labels in cell imaging. We have employed PEG-based conjugates for staining of HER2 biomarker on breast cancer cells. Due to the low optical background as well as low non-specific binding, the UCNP conjugates provided superior signal-to-background ratio (S/B = 319) compared to the fluorescence-based experiment with the identical immunoreagents (S/B = 6).

Links

• GA21-03156S, interní kód MU: Name: Foton-upkonverzní značky pro mikrofluidní jednomolekulové imunostanovení proteinových biomarkerů

Investor: Czech Science Foundation

• LQ1601, research and development project: Name: CEITEC 2020 (Acronym: CEITEC2020)

Investor: Ministry of Education, Youth and Sports of the CR

• LTAB19011, research and development project: Name: Luminiscenční imunostanovení jako citlivý nástroj pro diagnostiku nemocí včel

Investor: Ministry of Education, Youth and Sports of the CR, Sensitive bioanalytical tools for the surveillance of honey bee diseases, INTER-ACTION