Optical Constant Determination of Crosslinked ChitosanPolyethylene Glycol (PEG) using Attenuated Total Reflection Method by Surface Plasmon Resonance Phenomenon
Penulis/Author
ILYAS MAULANA YAHYA (1); Devy Pramudyah Wardani, S.Si., M.Sc. (2); Prof. Dr.Eng. Edi Suharyadi, S.Si., M.Eng. (3)
Tanggal/Date
2019
Kata Kunci/Keyword
Abstrak/Abstract
Application of chitosan as a sensing layer for heavy metal ions in surface plasmon
resonance (SPR)-based sensor with Kretschmann configuration has been done extensively using
polypyrrole and gruteraldehid. The deposition methods that are very widely used in depositing
chitosan onto the sensing surface are spin coating, electrodeposition and dip coating (for SPR
based fiber optic sensor). The deposition technique of chitosan-polyethylene glycol (PEG)
composite material as sensing layer in SPR based sensor by using the drop-casting method has
not been done to the best of our knowledge. In order to use chitosan-PEG composite material as
a sensing layer for heavy metal ion detection, it is necessary to determine the optical constant of
chitosan-PEG which is deposited by the drop-casting method. The refractive index of chitosanPEG with mass composition 0.4 grams chitosan and 0.04 grams PEG was determined by
attenuated total reflection (ATR) method by utilizing surface plasmon resonance phenomenon
on the prism/silver/chitosan-PEG interfaces in Kretschmann configuration. The refractive index
then was extracted from the ATR curve by using Winspall software. Based on the experimental
result, it was found that the ATR curve was shifted from 44.3° to 68.9° with the presence of a
chitosan-PEG layer deposited onto the silver surface, about 0.01 ml in solution form. From the
fitting result, it was found that the refractive index of chitosan-PEG was n = 1.32.
