Motoc, SorinaSorinaMotocSchinteie, BiancaBiancaSchinteiePop, AnielaAnielaPopNegrea, Sorina ClaudiaSorina ClaudiaNegreaCretu, CarmenCarmenCretuSzerb, ElisabetaElisabetaSzerbManea, FloricaFloricaManea2022-02-092022-02-092021-10http://hdl.handle.net/123456789/1788Nanomaterials, 2021, vol. 11, 2788. https://doi.org/10.3390/nano11112788.Two paste electrodes based on graphene quantum dots and carbon nanotubes (GRQD/CNT) and one modified with a homoleptic liquid crystalline Cu(I) based coordination complex (Cu/GRQD/CNT) were obtained and morphostructurally and electrochemically characterized in comparison with simple CNT electrode (CNT) for doxorubicine (DOX) detection in aqueous solutions. GRQD/CNT showed the best electroanalytical performance by differential pulse voltammetry technique (DPV). Moreover, applying a preconcentration step prior to the detection stage, the lowest limit of detection (1 ng/L) and the highest sensitivity (216,105 µA/mg·L−1) in comparison with reported literature data were obtained. Cu/GRQD/CNT showed good results using the multiple pulse amperometry technique (MPA) and a favorable shifting of the potential detection to mitigate potential interferences. Both GRQD-based paste electrodes have a great potential for practical utility in DOX determination in water at trace concentration levels, using GRQD/CNT with DPV and in pharmaceuticals formulations using Cu/GRQD/CNT with MPA.enGraphene quantum dotsLiquid crystalline Cu(I) coordination complexElectrochemical detectionDoxorubicineC-based paste electrodesresearch article10.3390/nano11112788