Synthesis of 0D to 3D hybrid-carbon nanomaterials carrying platinum(0) nanoparticles: Towards the electrocatalytic determination of methylparabens at ultra-trace levels

A generic synthetic methodology has been applied for functionalizing four conducting carbon nanoallotropes, such as 0D carbon nanohorns (CNHs), 1D carbon nanotubes (CNTs), 2D reduced graphene oxide (rGO) and 3D graphite (GP) with platinum(0) nanoparticles (Pt–NP), and exploited towards the electrocatalytic determination of methylparaben (MeP), which has been classified as a potential endocrine-disrupting chemical. After an accurate physical, electrochemical and electroanalytical characterization, the hybrid Pt–NP@CNTs yields detection limits at nM levels, rather than the μM levels obtained with the rest of carbon homologous because of the optimum carbon/nanoparticle composition ratio. The proposed electrochemical sensing system has also been successfully validated by comparison with the standard bench-top chromatographic tool (HPLC), demonstrating its feasibility for MeP quantification in real cosmetic samples at ultra-trace levels. According to the outstanding performance of the hybrid Pt–NP@CNTs electrochemical platform, it can be regarded as a potential alternative to the conventional HPLC technique for the development of rapid, straightforward, cost-effective, reproducible and highly sensitive electrochemical sensors to be exploited in pharmacological, biomedical and environmental fields.
This work was funded by the national DGI project FANCYCTQ2016-80030-R and the MINECO/FEDER project CTQ2015-64261-R, the Generalitat de Catalunya (2017-SGR-918) and the Spanish Ministry of Economy and Competitiveness, through the “Severo Ochoa” Programme for Centers of Excellence in R&D (SEV-2015-0496). The authors also than the Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN). Dr. J. Muñoz gratefully acknowledges the “Juan de la Cierva” programme. Dr. J. García-Antón acknowledges the Serra Húnter Program. I. Álvarez-Prada thanks the UAB for the PhD grant. Dr. J. Muñoz and I. Álvarez-Prada contributed equally to this work.