5-Formyl nicotinic acid methyl ester

5-Formyl nicotinic acid methyl ester (5-FNA) is a derivative of nicotinic acid that is used in research to measure the level of nicotine in urine. The affinity of 5-FNA for nicotine is much stronger than the affinity of acetone. 5-FNA is detectable in urine samples from humans and animals, and it can be used to study the health effects of tobacco use. It has also been used for toxicology research on animals and detection methods for tobacco use among humans. 5-FNA binds to nicotine receptors on cells and antibodies are produced against these receptors. The antibodies can be detected by an immunosorbant assay or radioimmunoassay, which are two techniques that are often used in 5-FNA studies.