Detection of L‐phenylalanine using molecularly imprinted solid‐phase extraction and flow injection electrochemiluminescence

Abstract

A novel flow injection electrochemiluminescence method combined with molecularly imprinted solid-phase extraction was developed for the determination of L-phenylalanine, in which ${\rm{Ru(bpy}})_3^{2 + }$ was used as the luminophor and indium tin oxide glass was modified as the working electrode. Molecularly imprinted polymers, synthesized by self-assembly with functional monomer and crossing linker, were used for the selective extraction of L-phenylalanine. In order to overcome the drawbacks of traditional electrochemiluminescence cells such as high IR drop, high over-potential and so on, a novel electrochemiluminescence cell was developed. The enhanced electrochemiluminescence intensity was linearly related with the concentration of L-phenylalanine in the range from 1.0×10(-7) to 5.0×10(-5) g/mL with a detection limit of 2.59×10(-8) g/mL. The relative standard deviation for the determination of 1.0×10(-6) g/mL L-phenylalanine was 1.2% (n=11). The method showed higher sensitivity and good repeatability, and was successfully applied for the determination of L-phenylalanine in egg white, chicken and serum samples. A possible mechanism for the enhanced electrochemiluminescence response on indium tin oxide glass is proposed.

Preparation of “dummy” l‐phenylalanine molecularly imprinted microspheres by using ionic liquid as a template and functional monomer

“…l ‐Phenylalanine ( l ‐Phe) is widely used in the pharmaceutical and food industries, such as for aminophenol transfusion, synthesis of anti‐cancer medication as well as in enzymatic reactions; it is also used as a nutrient source for pregnant women and in infant milk powder because it is one of the essential amino acids in the human body that can only be ingested . The concentration of l‐ Phe in the human blood is a key indicator for the diagnosis and dietary treatment of phenylketonuria .…”

A complex imprinted polymer membrane combined with solid phase fluorescence detection for selective analysis of l-phenylalanine in water-abundant samples

“…The aromatic amino acid L-phenylalanine (phe) is one of the essential amino acids in the human body, which cannot be synthesized by the human body and thus has to be supplied from the diet. Phe is used widely in food and pharmaceutical products, 10 such as an intermediate of anti-cancer medicines, as a nutritional additive and as a avoring agent of drinks or food. 11 Besides, Phe works as a building block of aspartame, a very widely used low-calorie articial sweetener.…”