Abstracts Book - IMRC 2018

• SB1-P021
SYNTHESIS AND CHARACTERIZATION OF POLYELECTROLYTES AS
FLUORESCENT pH SENSORS.
Estefania Terrazas Caro 1,2
1 Centro de Investigación en Materiales Avanzados, S.C., Laboratorio de Análisis Térmico,
Mexico. 2 Universidad Autónoma de Chihuahua, Facultad de Ciencias Químicas, Mexico.
The determinations of acidity in aqueous solutions present endless applications,
that is why the implementation of sensors. The pH sensors show some limitations,
which are associated with the processing materials, since these are sometimes not
sensitive to extreme pH, as well as the shapes and dimensions their
application. Polymeric materials represent a viable alternative for these purposes.
Chitosan is the most abundant biopolymer after cellulose [1,2], on the other hand
it is biodegradable, biocompatible, and has shown, according to previous studies,
sensitivity to pH. [3-4]. This material has been combined with various compounds
such as carboxymethylcellulose (CMC), a cellulose derivative that shows good
barrier properties against oxygen and lipids [5], since CMC is an ionic polymer, and
chitosan is a cationic polymer, it is biocompatible by the formation of strong ionic
crosslinking bonds, so it could be predicted that it will be a good base for the
flavylium salt, since it has shown flourecent activity. Fluorescent pH sensors have
attracted considerable attention due to their high sensitivity, versatility of formats
and well-established reference reading systems, such as ratiometric measurements
of two wavelengths or double life referencing [7-8]. For the formation of the
polyelectrolyte, Chitosan, Carboxymethylcellulose, 2% Glacial Acetic Acid and
distilled water were used. The sample was doped with Flavialium salt, tested with
three different concentrations. The synthesis of polyelectrolyte of chitosancarboxymethylcellulose
was achieved with the successful incorporation of the
flavylium salt, thus achieving the synthesis of the sensor films. We proceeded to the
chemical characterization by implementing Infrared Spectrometry by Fourier
Transforms (FTIR), Nuclear Magnetic Resonance Spectrometry (NMR), Raman
Spectrometry and Flourometry finding fluorescent activity.
Acknowledgment:
Authors thanks the National Science and Technology Minister (CB-2013-01
number 222847) for financial funding.
Keywords: pHsensor, flourescence, chitosan
Presenting authors email: estefaniaterrazascaro@gmail.com