The coupling of magnetic separation of methamphetamine with cucurbituril-mediated fluorescence analysis

Methamphetamine (MA) abuse still constantly increases in the world, which is seriously harmful for people's health. Cucurbituril-mediated sensors for detection of illicit drugs have received growing attention. However, urine samples contain inorganic salts with high concentration, which could disturb the interaction between cucurbituril host and fluorescence dye or target guest. Magnetic solid phase extraction (MSPE) technology exhibits excellent potential to remove impurity and ameliorate sensitivity for detection in complex biofluids. This work demonstrated a strategy for MA detection, in which MSPE was coupled with cucurbituril-mediated chemosensor to reduce interference of salts and overcome dilution issues in biological samples. The magnetic nanoparticles Fe 3 O 4 @polydopamine (PDA) were used as adsorbent and chemosensor 2∗proflavine@cucurbit[8]uril (2 PF@Q[8]) was applied for the fluorescence detection of MA. In the end, a linear range of 1.3–20 ng/mL and limit of detection of 0.4 ng/mL were achieved. Besides, the proposed method showed a pronounced selectivity in the presence of other illicit drugs. In general, we introduced an example focusing on coupling of MSPE with cucurbituril-mediated chemosensor, where small organic molecule MA was adsorbed and retained while inorganic salts were separated. This study underscores the potential of coupling MSPE with cucurbituril-mediated chemosensor in biological samples.