A New Pyrrole-2-carboxaldehyde Functionalized Chitosan-Cu(II) Complex-based Chemosensor for Iodide Anion in Aqueous Media

Samuel Adeolu Olugbemi *

Department of Chemistry, College of Physical Sciences, Federal University of Agriculture Abeokuta, Ogun, Nigeria and Department of Science Laboratory Technology, School of Science and Technology, The Gateway Polytechnic, Saapade, Ogun State, Nigeria.

Lateefah Olanike Adebayo

Department of Chemistry, College of Physical Sciences, Federal University of Agriculture Abeokuta, Ogun, Nigeria.

Sheriff Adewuyi

Department of Chemistry, College of Physical Sciences, Federal University of Agriculture Abeokuta, Ogun, Nigeria.

*Author to whom correspondence should be addressed.


Iodine is an essential ingredient in thyroid hormones of which both low and high intakes may cause thyroid disease. This study develops a Pyrrole-2-Carboxaldehyde functionalized chitosan-Cu(II) Complex [PCAFC-Cu(II)] chemosensor, for quick and easy detection of iodide ions from its aqueous solutions. PCAFC-Cu(II) complex was synthesized from a simple condensation reaction of chitosan (CS) and pyrrole-2-carboxaldehyde (PCA) along with an aqueous solution of copper(II) salt. The starting materials and the products were characterized by spectroscopic (FT-IR and UV-Visible), X-ray powder diffraction, and microscopic methods (Scanning Electron Microscopy). The PCAFC-Cu(II) colorimetric sensing of I- revealed a color change adduced to the formation of a hydrogen bond or deprotonation of the complex matrix. Colorimetric detection for I- ions was obtained with a detection limit (LoD) of 0.005 M and the complex has high specificity for I- ions detection from a solution consisting of several anions. The synthesized complex [PCAFC-Cu(II)] could serve as an on-site reagent for the qualitative detection of iodide ions.

Keywords: Chemosensor, colorimetric detection, complex, anions, condensation, deprotonation

How to Cite

Olugbemi, S. A., Adebayo , L. O., & Adewuyi , S. (2023). A New Pyrrole-2-carboxaldehyde Functionalized Chitosan-Cu(II) Complex-based Chemosensor for Iodide Anion in Aqueous Media. Chemical Science International Journal, 32(5), 1–12. https://doi.org/10.9734/CSJI/2023/v32i5855


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