High performance liquid chromatography-tandem mass spectrometry determination of patulin and ochratoxin a in commercial fruit juices after their extraction with a green synthesized metal organic framework-based dispersive micro solid phase extraction procedure

Herein, for the first time, a vitamin-based metal organic framework is synthesized from vitamin B3 (as a bio linker) and cobalt ions (as a metallic center) and employed as an efficient sorbent in dispersive micro solid phase extraction of patulin and ochratoxin A from fruit juice samples. The extracted analytes are quantitatively analyzed using high performance liquid chromatography-tandem mass spectrometry. In this work, after synthesizing the sorbent, it was characterized using X-ray diffraction, Fourier transform infrared spectrophotometry, scanning electron microscopy, nitrogen adsorption/desorption, and energy-dispersive X-ray spectroscopy. In the following, it was used as an efficient sorbent in the offered microextraction method and numerous parameters that could affect extraction efficiency of the method were investigated and optimized using response surface methodology. Based on the method validation results, limits of detection and quantification were 39.6 and 131.7 ng L-1 for patulin, and 24.8 and 82.6 ng L-1 for ochratoxin A, respectively. The extraction recoveries for patulin and ochratoxin A were 75 and 87%, respectively. Repeatability of the suggested approach, expressed as relative standard deviations, were equal to or<5% (at a concentration of 250 ng L-1 of each analyte). Also, environmentally friendly synthesis of the metal organic framework (using vitamin B3 as a linker, water as the reaction solvent, and mild conditions) and usage low amount or volumes of the sorbent and organic solvents in the microextraction procedure were other advantages of the current work.

Automated summary

For the first time, a vitamin-based metal organic framework was synthesized and employed for efficient dispersive micro solid phase extraction of patulin and ochratoxin A from fruit juice samples. The analytes were quantitatively analyzed using high performance liquid chromatography-tandem mass spectrometry. The method was validated and showed good results in terms of detection limits, extraction recoveries, and repeatability.