Chenyi Li,Hongchao Geng,Xingqi Zhu,Chan Gao,Ning Jiang,Yan Qiao,Qingyun Cai
Concerns about bioaccumulation, persistence and toxicity have led to a lot of researches on perfluorinated compounds (PFCs). In order to identity PFCs in real sample, self-assembled TiO 2 nanosheets (TiO 2 NS) were fabricated by an one-step hydrothermal method and applied as matrix for the surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF MS) detection of PFCs. Compared to the commercial P25 TiO 2 , the proposed self-assembled TiO 2 nanosheets matrix is better reproducibility and higher sensitivity benefiting from the unique hexagon structure of TiO 2 NS. 22 and 12 PFCs have been detected in water samples collected from locations near the outlets of a factory and a waste-water treatment plant, respectively. The proposed method can be a promising tool for high-throughput detect of trace PFCs in real samples.
Chan Gao,Deshuai Zhen,Ni He,Zhengbin An,Qiulan Zhou,Chenyi Li,Craig A. Grimes,Qingyun Cai
High surface area (136 m 2 g −1 ) nanoporous two-dimensional TiO 2 nanoflakes are applied as an adsorbent and meanwhile a matrix for toxic small molecule analysis using positive-ion surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF MS). The TiO 2 nanoflakes enable one-step enrichment and analysis, greatly simplifying the analysis technique. Due to the high enrichment efficiency and low background noise, small molecule organic contaminants at ppt or even sub-ppt concentrations such as malachite green (10 pg/mL), leucomalachite green (10 pg/mL), cetyltrimethylammonium bromide (0.001 pg/mL), rhodamine B (0.001 pg/mL), and crystal violet (0.1 pg/mL) were detected. In addition, malachite green and its metabolite leucomalachite green at ng/mL concentrations were successfully detected from fish blood and fish extracts, and crystal violet and its homologues at ng/cm 2 concentrations were detected from inks on thermal receipt papers obtained from local supermarket.