A novel magnetic fluid for ultra-fast and highly efficient extraction of N1-methylnicotinamide in urine samples

To overcome the low concentration and matrix complexity of N1-methylnicotinamide (MeNam) in biological samples, this work developed a method for the detection of MeNam in urine samples using a Fe3O4@hydroxypropylmethylcellulose@2,3-dimercaptosuccinic acid (Fe3O4@HPMC@DMSA) magnetic fluid as a pre-treatment material in combination with high performance liquid chromatography. The novel adsorbent material exhibited ultra-fast adsorption kinetics and a large adsorption capacity because Fe3O4@HPMC@DMSA NPs acted as a homogeneous magnetic fluid with more varieties and quantities of interaction sites (hydrogen-bonding interaction and electrostatic interaction). The limit of determination for MeNam was 0.05 μg mL−1 with Fe3O4@HPMC@DMSA NPs. Recoveries of spiked urine samples ranged between 95.49% and 106.4%, indicating that the developed method was promising for the accurate quantification of trace amounts of MeNam in urine samples. It provides research value for the rapid assessment of the nutritional effects of NMN dietary supplements and offers a sensitive assay for metabolism studies of related functional foods.