López Mayán, Juan JoséÁlvarez-Fernández, BlancaPeña Vázquez, Elena MaríaBarciela Alonso, María CarmenEspiña, BegoñaMoreda Piñeiro, AntonioMaguire, JulieMackey, MickQuarato, MonicaPinheiro, IvoneEspiña, BegoñaRodríguez-Lorenzo, LauraBermejo Barrera, Pilar2023-11-132023-11-132023-07-07Microchim Acta 190, 287 (2023)0026-3672http://hdl.handle.net/10347/31259A bioaccumulation study in red (Palmaria palmata) and green (Ulva sp.) seaweed has been carried out after exposure to different concentrations of citrate-coated titanium dioxide nanoparticles (5 and 25 nm) for 28 days. The concentration of total titanium and the number and size of accumulated nanoparticles in the seaweeds has been determined throughout the study by inductively coupled plasma mass spectrometry (ICP-MS) and single particle-ICP-MS (SP-ICP-MS), respectively. Ammonia was used as a reaction gas to minimize the effect of the interferences in the 48Ti determination by ICP-MS. Titanium concentrations measured in Ulva sp. were higher than those found in Palmaria palmata for the same exposure conditions. The maximum concentration of titanium (61.96 ± 15.49 μg g−1) was found in Ulva sp. after 28 days of exposure to 1.0 mg L−1 of 5 nm TiO2NPs. The concentration and sizes of TiO2NPs determined by SP-ICP-MS in alkaline seaweed extracts were similar for both seaweeds exposed to 5 and 25 nm TiO2NPs, which indicates that probably the element is accumulated in Ulva sp. mainly as ionic titanium or nanoparticles smaller than the limit of detection in size (27 nm). The implementation of TiO2NPs in Ulva sp. was confirmed by electron microscopy (TEM/STEM) in combination with energy dispersive X-Ray analysis (EDX)eng© The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were madeCreative Commons Attribution 4.0 International LicenseBioaccumulation Titanium dioxide nanoparticles Seaweed Alkaline extraction Single particle inductively coupled plasma mass spectrometry Electron microscopy with energy dispersive X-ray analysisjournal article10.1007/s00604-023-05849-11436-5073open accessCreative Commons Attribution 4.0 International License