Primjena ugljikovih nanovlakana i grafena u razvoju novog senzora za analizu nepafenaka

master's thesis

• Title (english): Carbon nanofibers and graphene application in development of a new sensor for nepafenac analysis
• Author: Ivana Jurić
• Mentor: Biljana Nigović (mentor)
• Committee member: Biljana Nigović (predsjednik povjerenstva)
• Committee member: Miranda Sertić (član povjerenstva)
• Committee member: Petra Turčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of pharmaceutical analysis); Zagreb
• Defense date and country: 2018-09-14, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Pharmacy; Pharmacy

Abstract

Nepafenak je nesteroidni protuupalni lijek koji se koristi za prevenciju i liječenje postoperativne boli i upale povezane s operacijom katarakte te smanjenje rizika za pojavu makularnog edema nakon operacije katarakte kod bolesnika s dijabetesom.
U eksperimentalnom dijelu rada, proveden je niz pokusa koji čine dio razvoja nove voltametrijske metode za određivanje nepafenaka. Ispitan je utjecaj modifikacije radne elektrode od staklastog ugljika na voltametrijski odziv nepafenaka pri čemu su korištene grafen nanopločice i/ili ugljikova nanovlakna u otopini kitozana ili nafiona. Napravljen je probir pH vrijednosti Britton-Robinson pufera koji je služio kao elektrolit za mjerenja. Jedan od koraka u radu bila je optimizacija parametara pravokutnovalne voltametrijske metode. Cikličkom voltametrijom utvrđeno je da je oksidacija nepafenaka na modificiranoj elektrodi adsorpcijski kontrolirana elektrodna reakcija te da bi se adsorpcija lijeka mogla koristiti u razvoju osjetljive stripping voltametrijske metode za analizu nepafenaka. Određeno je optimalno vrijeme i potencijal akumulacije za ukoncentriravanje analita na površini modificirane elektrode. Naposljetku, nakon što su parametri i uvjeti metode bili u potpunosti definirani, odrađen je jedan dio validacije metode. Naime, proveden je pokus koji je za cilj imao utvrditi područje linearnosti i dati eksperimentalne kalibracijske krivulje koje bi se mogle koristiti kod određivanja sadržaja nepafenaka.

Abstract (english)

Nepafenac is a nonsteroidal anti-inflammatory drug and is used for prevention and treatment of pain and inflammation after the cataract surgery. It is also used as a prophylactic drug for prevention of macular oedema after the cataract surgery in patients with diabetes.
In the experimental part of this thesis, a number of experiments were carried out as a part of development of a new voltametric method for the determination of nepafenac.The influence of surface modification of working glassy carbon electrode on nepafenac response was investigated and the graphene nanoplatelets and/or carbon nanofibers in solutions with chitosan or nafion were used. The selection of a pH values of Britton-Robinson buffer solution which was used as an electrolyte solution during measurements was made. The optimization of the parameters of a method for a square-wave voltammetry was one of the steps in an experimental procedure. Cyclic voltammetry has shown that the oxidation of nepafenac on modified electrode is an adsorption-controlled electrode reaction. Furthermore, adsorption of nepafenac could be used in development of a sensitive stripping voltametric method for analysis of nepafenac. Duration of accumulation and deposition potential were determined. Last but not least, after all the parameters of the new voltammetric method for determination of nepafenac were entirely defined one part of validation of the new method was carried out. In short, an experiment which had to determine the linearity range was performed. That same experiment gave a calibration curve that could be used for a quantitative determination of nepafenac.

• Keywords: nepafenak; voltametrija; ciklička voltametrija; pravokutnovalna voltametrija; grafen nanopločice; ugljikova nanovlakna; modificirana elektroda
• Keywords (english): nepafenac; voltammetry; cyclic voltammetry; square-wave voltammetry; graphene nanoplatelets; carbon nanofiber; modified electrode
• Language: croatian
• URN:NBN: urn:nbn:hr:163:819659
• Study programme: Title: Pharmacy; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra farmacije (magistar/magistra farmacije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-04-09 06:56:49