Title Nosivi optički (bio)kemijski senzori na tekstilu i papiru Title (english) Wearable optical (bio)chemical sensors on textiles and paper Author Juraj Kasač Mentor Ivana Steinberg (mentor)Committee member Ivana Steinberg (predsjednik povjerenstva)Committee member Petar Kassal (član povjerenstva)Committee member Ema Horak (član povjerenstva)Granter University of Zagreb Defense date and country 2018-09-28, Croatia Scientific / art field, NATURAL SCIENCES Abstract Zahvaljujući današnjim brojnim tehnološkim dostignućima, fokus istraživanja (bio)kemijskih senzora usmjeren je prema realizaciji nosivih analitičkih uređaja. Nosivi (bio)kemijski senzori su alati koji omogućavaju kontinuiranu i neinvazivnu analizu sadržaja bioloških fluida (npr. znoj, suze, slina, međustanična kapljevina ili dah) kao i detekciju određenih supstanci u okolišu nositelja senzora. Optički (bio)kemijski senzori su vrsta (bio)kemijskih senzora pomoću kojih se dolazi do željene informacije pomoću interakcije s elektromagnetskim zračenjem. U literaturi se često spominju pod ključnom riječi „optode“, zbog velike sličnosti s njihovim elektrokemijskim ekvivalentima-elektrodama. Problemi kao što su odabir pogodnih materijala, izvor napajanja te vjerodostojnost prikupljenih podataka za analizu glavni su razlog komercijalne nedostupnosti nosivih kemijskih senzora. U zadnje vrijeme, sve je veći interes za korištenjem papira i tekstila kao supstratnih materijala. Dostupnost, pristupačnosti te niska cijena papira sasvim su opravdani razlozi za odabir takvog supstrata. S druge strane, tekstilni senzori su s praktičnog stajališta najinteresantniji kako bi se već nalazili integrirani u odjevnim predmetima. Cilj ovog rada bio je ispitati dobro utvrđeni mehanizam ion-selektivnih optoda na različitim supstratima. Pripravljeni su senzori za kalij na bazi valinomicina i lipofiliziranog Nile Blue indikatorskog bojila, te je provedena njihova analitička karakterizacija s potencijalnom primjenom u analizi sadržaja znoja. U okviru ovog istraživanja, kromatografski papir se pokazao kao najbolji supstrat. Eksperimentalni rezultati ispitivanja optoda na kromatografskom papiru su pokazali da dinamičko područje obuhvaća preko tri reda veličine (10^-1 M - 10^-4 M K+) koje je zadovoljavajuće za praktičnu primjenu s obzirom na činjenicu da se prosječna koncentracija kalijevih iona u znoju nalazi upravo u tom intervalu. Treba naglasiti da je upotrebljivost ovih senzora limitirana zbog poznatog problema s ispiranjem osjetilnih komponenti senzora što pokazuju rezultati karakterizacije; obnovljivost, ponovljivost i stabilnost. Ovako pripravljene papirne kalij-selektivne optode bi se mogle koristiti za predviđenu aplikaciju u obliku jednokratnih test-traka.
Abstract (english) Numerous advancements in today’s technology had impact on research of (bio)chemical sensors. Focus has been shifted towards realization of wearable analytical devices. Wearable (bio)chemical sensors are analytical tools that provide the opportunity for continuous and non-invasive analysis of body fluid content (such as sweat, tears, saliva, interstitial fluid or breath), as well as the ability to detect substances in the environment of their user. Optical (bio)chemical sensors represent the subclass of (bio)chemical sensors where interaction with electromagnetic radiation is employed in order to extract useful information. They are most commonly named “optodes” in the literature, due to great similarity with their electrochemical equivalents-electrodes. Certain problems such as choosing appropriate materials, external power sources and credibility of harvested data still represent the challenge that needs to be resolved in order to start commercial production of wearable (bio)chemical sensors. A growing interest in using paper and textile as substrate materials has been observed. Availability and affordability of low-cost paper are main reasons to choose this material. On the other hand, textile-based sensors would be most practical due to simple integration with existing clothing material. The ultimate goal of this thesis was to investigate the mechanism of ion-selective optodes on different substrates. Potassium-selective optodes based on valinomycin carrier and lipophilized Nile Blue indicator dye were fabricated with potential application in analyzing the sweat content. Fabrication of sensors was followed with their analytical characterization. Experimental results have shown that chromatography grade paper seems to be the most appropriate substrate material, considering the investigated mechanism. Such paper-based optodes were characterized in greater detail, exhibiting dynamic range that covers over three orders of magnitude (10^-1 M - 10^-4 M K+), making them suitable for predicted application. Average potassium concentration in human sweat lies within that range. It should be emphasized that the usability of these sensors is limited owing to the well-known leaching problem, where sensing components are being washed out of the system. Characterization parameters such as repeatability, reproducibility and stability have clarified that apparent problem. Paper-based potassium-selective optodes investigated in this research could therefore be used for predicted application as single-use, disposable paper strips.
Keywords
(bio)kemijski senzori
optički
nosivi
ion-selektivne optode
indikatorsko bojilo
senzori na bazi papira
senzori na bazi tekstila
kalij
znoj
jednokratne test-trake
Keywords (english)
(bio)chemical sensors
optical
wearable
ion-selective optode
indicator dye
paper-based senors
textile-based sensors
potassium
sweat
disposable paper strips
Language croatian URN:NBN urn:nbn:hr:149:206968 Study programme Title: Applied Chemistry - Graduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry Type of resource Text File origin Born digital Access conditions Open access Terms of use Created on 2020-11-02 12:42:40
