Near-infrared polymethine fluorophores for targeted biomarker detection

PASTUCHA, Matěj, Martin POTRUSIL, Zdeněk FARKA and Peter ŠEBEJ. Near-infrared polymethine fluorophores for targeted biomarker detection. In XX. Interdisciplinary meeting of young life scientists. 2021.

Basic information

• Original name: Near-infrared polymethine fluorophores for targeted biomarker detection
• Authors: PASTUCHA, Matěj, Martin POTRUSIL, Zdeněk FARKA and Peter ŠEBEJ.
• Edition: XX. Interdisciplinary meeting of young life scientists, 2021.

Other information

• Original language: English
• Type of outcome: Presentations at conferences
• 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

Abstract

Fluorescent dyes are widely used in life-sciences and medicine. They are frequently employed as imaging agents, alone or in connection with antibodies in immunofluorescence experiments. Biological tissues absorb visible light; therefore, a tissue-transparent window (TTW) in the near-infrared (NIR) region is preferred for imaging purposes, e.g. in the fluorescence image-guided surgery. Polymethine dyes are great candidates for applications in the TTW, and their properties can be tuned by changes in the chromophore length and substituents. We chose the indocyanine green (ICG) as an initial model (the only NIR emitting dye certified by FDA for use in clinical medicine). It is usually used as a contrast agent with limited selectivity, but when conjugated to an antibody, it can also be employed for specific visualization of target biomarkers. However, its conjugation is not without pitfalls. The dye inflicted partial aggregation of the antibody during conjugation. Furthermore, we observed a high level of nonspecific binding in a model immunocytochemical labeling of HER2 biomarker on breast cancer cell lines. This was probably caused by the high tendency of the dye to bind to proteins. To overcome this limitation, we conjugated a heptamethine with similar spectral properties, Cyanine 7 (Cy7), to the antibody via Cu-catalyzed click chemistry. The conjugate provided a much higher specificity of labeling, making it a superior NIR dye for immunofluorescence experiments in the TTW.

Links

• GJ20-30004Y, research and development project: Name: Nové strukturní motivy pro rozšíření možností lineárních polymethinových barviv

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