3D-printed solid phase microextraction fiber based on Co-Al layered double hydroxide nanosheets; application in...

3D printing technology has attracted great attention in various fields of science and technology. Application of this technology in manufacturing analytical tools is developing fast. High precision in manufacturing designed objects, fast production and low cost also green production approach by using biodegradable materials like polylactic acid is promising bright future in scientific researches. The development of new approaches in improving the functional groups of the surface of 3D printed objects in order to make 3D printed parts more functional with conventional 3D printed materials, causes the entry of many advanced materials in this field. In this study, a novel solid phase microextraction fiber was prepared based on Co-Al layered double hydroxide (LDH) nanosheets in-situ growth on 3D-printed aluminum-polylactic acid (PLA) composite and its application for determination of phenolic acids (PAs) including vanillic acid (VA), ferulic acid (FA), p-coumaric acid (p-CA), p-hydroxybenzoic acid (HBA), protocatechuic acid (PCA) and caffeic acid (CA) in fruit juice samples was investigated. The proposed fiber was prepared via a robust one-step hydrothermal synthesis of Co-Al LDH on an anodized 3D-printed Al-PLA fiber. Factors crucial for the extraction, including pH, extraction and desorption time and ionic strength were explored in detail. Under the optimal experimental conditions, for all PAs except PCA, LOD, LOQ and LDR were obtained as 0.03, 0.1 and 0.1-100.0 µgL^-1, respectively. For PCA, LOD, LOQ and LDR were obtained as 0.15, 0.50 and 0.5-100.0 µgL^-1, respectively.