A Fluorosensor with Immobilized Cyclodextrin As A Substrate

Abstract

A flow-through optosensor for phenylalanine and tyrosine is described in this paper. The sensor is developed in conjunction with a flow-injection analysis system and uses immobilized β-cyclodextrin as the sensing agent. The analytical performance characteristics of the proposed sensor for analysis of very low levels of phenylalanine and tyrosine were as follows: the detection limits for phenylalanine and tyrosine were 0.20 μg ml⁻¹ and 8.9 ng ml⁻¹, respectively. The observed relative standard deviations were 1.03% for 50 μg ml⁻¹ of phenylalanine (n = 7) and 3.6% for 0.1 μg ml⁻¹ of tyrosine (n = 7), respectively.

Keywords:

• immobilized cyclodextrins
• optosensor
• phenylalanine
• tyrosine