| Autor: |
Panikar SS; Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México., Sekhar Reddy KC; Centro de Investigación y de Estudios Avanzados (CINVESTAV) Unidad Querétaro, Querétaro, 76230, México.; Department of Electrical and Electronics Engineering, Birla Institute of Technology and Science Pilani Hyderabad Campus, Hyderabad 500078, India., Gonzalez AL; Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apdo. Post. J-48, Puebla, 72570, México., Ramírez-García G; Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México., Rodríguez ÁG; Coordinación para la Innovación y la Aplicación de la Ciencia y la Tecnología (CIACYT), Universidad Autónoma de San Luis Potosí (UASLP), Álvaro Obregón 64, 78000 San Luis Potosí, S.L.P. México., Mondragon Sosa MA; Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México., Salas P; Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México., Mota-Morales JD; Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México. |
| Abstrakt: |
Exceptional surface enhanced Raman scattering (SERS) can be achieved by on-demand mechanisms mediated by the formation of three-dimensional (3D) network supporting hotspots. Herein, a deep eutectic solvent (DES) is used to fabricate plasmonic aerogels as sustainable SERS substrates consisting of different gold nanoparticle (AuNP) heterostructures synthesized in the presence of cellulose nanocrystals (CNCs). This analytical approach is based on the AuNPs 3D arrangement within the CNC matrix, where the transient inter-CNCs interactions collapse after loading with the analyte aqueous solution, forming hotspots on demand. Theoretical calculations support the on-demand SERS mechanism, which consists of the hotspot formation by bringing the AuNPs closer upon activation with the liquid sample loading. To evaluate the plasmonic aerogel performance as a sensing platform, the organophosphorus pesticides edifenphos and parathion were tested in rice and tea extracts. Also, the detection of Methylene Blue in fish muscle extract resulted in a detection limit of 9.8 nM. The results demonstrate that the 3D plasmonic aerogel exhibits significantly higher SERS enhancement and sensitivity when compared to conventional 2D SERS substrates. The use of a green designer solvent, biobased ingredients, and the introduction of on-demand SERS-based sensing pave the way for further developments in the analysis of liquid samples within a sustainable framework. |
