Capillary electrophoresis coupled to chemometrics for analysis of carbon dots in nanoparticles mixtures

OLIVEIRA, LEVI; ARROYAVE, MANUEL; PISTONESI, MARCELO F.; FRAGOSO, WALLACE; SPRINGER, VALERIA

ELECTROPHORESIS

WILEY-V C H VERLAG GMBH

Año: 2022

0173-0835

Since their discovery in 2004, carbon dots (CDs) have attracted attention due to their intrinsic physicochemical properties and the easy synthesis from simple precursors. However, quantification of CDs in mixtures of nanoparticles with similar sizes and surface functionality is still a challenging issue for research applications or regulatory purposes. In this work, CDs and silver nanoparticles were firstly synthesized under alkaline conditions by using glucose as precursor and capping agent, respectively. Mixtures of these nanoparticles were made at micromolar range, without purification, and then analyzed by capillary electrophoresis-diode array detection (CE-DAD), using an electrolyte solution composed by 20 mM sodium borate and 20 mM sodium dodecylsulfate (SDS) at pH 8.5, in a total time lower than 15 min. The three-way electrophoretic data was then decomposed by advanced chemometric models, parallel factor analysis (PARAFAC) and multivariate curve resolution-alternating least-squares (MCR-ALS). The explained variances for both models were 95.8% (PARAFAC) and 85.3% (MCR-ALS). In both cases, the quality of the results was verified by the Root Mean Square Standard Deviation Coefficient Variation (RMSCV), which resulted lower than 5%, and no significant bias were observed at 95% of statistical confidence. Satisfactory prediction for CDs concentration was obtained with recovery values between 80.0-115%.