Abstract:
Two inexpensive and simple methods for synthesis of carbon nanodots were applied and
compared to each other, namely a hydrothermal and microwave-assisted method. The synthesized
carbon nanodots were characterized using transmission electron microscopy (TEM), ultravioletvisible
(UV-Vis), photoluminescence (PL), Fourier transform-infrared spectroscopy (FTIR), and X-ray
diffraction (XRD). The synthesized microwave carbon nanodots had smaller particle size and were
thus chosen for better electrochemical performance. Therefore, they were used for our modification
process. The proposed electrodes performance characteristics were evaluated according to the
IUPAC guidelines, showing linear response in the concentration range 106–102, 107–102, and
108–102 M of tobramycin with a Nernstian slope of 52.60, 58.34, and 57.32 mV/decade for the
bare, silver nanoparticle and carbon nanodots modified carbon paste electrodes, respectively. This
developed potentiometric method was used for quantification of tobramycin in its co-formulated
dosage form and spiked human plasma with good recovery percentages and without interference of
the co-formulated drug loteprednol etabonate and excipients.