A team has created a new way to produce organic fluorophores using formaldehyde.
A research group led by Professor Young-Tae Chang from POSTECH’s Chemistry Department, along with Dr. Sun Hyeok Lee from POSTECH’s Basic Science Research Institute, has achieved a significant advancement in the cost-effective and atom-efficient production of organic fluorophores using formaldehyde, the simplest carbon compound. Their results were published on September 18 in “Angewandte Chemie International Edition,” a leading journal in chemistry.
Organic fluorophores are substances that can glow by absorbing certain light wavelengths, and they are extensively used in medical diagnostics and bioimaging, including tracking cancer cells and analyzing genetics. However, the traditional method of creating trimethine cyanine (Cy3), a popular type of organic fluorophore, usually involves a complicated compound with a heavy molecular weight, resulting in many byproducts and reduced atomic efficiency.
To tackle this problem, the team chose to use formaldehyde (HCHO), which consists of one carbon (C) atom, two hydrogen (H) atoms, and one oxygen (O) atom. Although formaldehyde can be toxic in biological systems by interacting with proteins and DNA, it is a useful agent in organic synthesis for creating new carbon-carbon links.
By substituting formaldehyde for the usual complex compounds in the carbon addition step of Cy3 synthesis, the researchers were able to significantly decrease the molecular size needed for the reaction, thus enhancing atomic efficiency. They also simplified the previously lengthy multi-step approach to asymmetric Cy3 synthesis into a single reaction, removing unnecessary steps and increasing the efficiency of the synthesis process.
The team investigated if their method could be applied in living organisms since small amounts of formaldehyde are naturally produced during metabolism. When analyzing rat small intestine tissue, they discovered that the inflammation-affected group had a dimmer fluorescence signal compared to the control group. This was linked to lower levels of formaldehyde during inflammation, which hindered Cy3 synthesis. These observations suggest that their technique is suitable for both in vitro and in vivo applications.
Professor Young-Tae Chang noted, “This is the first successful synthesis of Cy3 molecules using formaldehyde.” He added, “Our approach is not only economical and atom-efficient but also viable in living systems, broadening the potential uses of organic fluorophores in life sciences and diagnostics.”
The research received funding from the Ministry of Science and ICT and the Glocal University 30 Project.
