Naslov
Novel electrochemical methods in analysis of selected drugs using carbon nanotubes-based sensors

Autori
Sadiković, Mirela

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, doktorska disertacija

Fakultet
Farmaceutsko-biokemijski fakultet

Mjesto
Zagreb

Datum
02.02

Godina
2018

Stranica
121

Mentor
Nigović, Biljana

Ključne riječi
Multi-walled carbon nanotubes, Zirconium oxide nanoparticles, Nafion, Voltammetry, Electrochemical nanosensors, Ondansetron, Morphine, Ropinirole, L-dopa, Mesalazine, Metabolite of mesalazine, Nebivolol

Sažetak
Due to strict requirements regarding quality control of pharmaceuticals and with the aim of obtaining maximal efficacy and safety of drug therapy for patients, there is a constant demand for developing new reliable analytical methods to determine drug concentrations in complex samples. Electroanalytical techniques, especially voltammetric, represent a powerful analytical tool. Electrochemical nanosensors have recently found extensive applications in pharmaceutical analysis. Therefore, the aim of this doctoral thesis was to develop new electroanalytical methods for the determination of selected pharmaceuticals in dosage forms and biological fluids using novel sensors based on multi-walled carbon nanotubes dispersed in Nafion matrix, as well as their combination with zirconium oxide nanoparticles. Electrochemical behaviour of selected drugs was examined by cyclic voltammetry to get an insight into their redox mechanism at modified electrodes. Experimental conditions and instrumental parameters that could affect the electroanalytical performance of proposed sensors were carefully optimised. New methods were validated according to ICH guidelines. Direct pulse voltammetric techniques (square- wave or differential pulse) were used to determine the content of ropinirole, L-dopa, mesalazine and nebivolol in tablets, except for ondansetron in which case adsorptive stripping procedure was employed. The good recoveries indicated that excipients did not interfere with the assay of active ingredient in any case. In comparison to the high performance liquid chromatographic methods, there were no significant differences regarding the accuracy and precision ; however voltammetric techniques offer high sensitivity, rapid response and simplicity. Finally, nanosensors were applied for the simultaneous quantification of selected pharmaceuticals with other co-administered drugs in therapy (such as ondansetron with morphine and ropinirole with L-dopa) or their metabolites (mesalazine and N-acetylated metabolite) in human serum samples using adsorptive stripping voltammetry. Integration of the nanoparticles in the sensor improved notably the determination of therapeutic concentrations of nebivolol in serum. Excellent recoveries in the range of 98.7 – 102.6 % were obtained in all cases, without the need for sample pretreatment. A considerable enhancement effect on voltammetric responses of selected drugs, is due to synergy of remarkable properties of nanomaterials and cation-exchange polymer, that enhanced the preconcentration of positively charged drug molecules.

Izvorni jezik
Engleski

Znanstvena područja
Farmacija

Napomena
Ova disertacija napisana je na engleskom jeziku temeljem članka 15. Pravilnika o doktorskom studiju (Farmaceutsko-biokemijski fakultet u Zagrebu, 2017.) Disertacija je pisana kao skup objavljenih znanstvenih radova popraćen kritičkim preglednim poglavljem (tzv. skandinavski model), temeljem članka 14. Pravilnika o doktorskom studiju (Farmaceutsko-biokemijski fakultet u Zagrebu, 2017.)

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