Electroactive Core–Shell Chitosan-Coated Lanthanum Iron Oxide as a Food Freshness Level Indicator for Tyramine Content Determination

Abstract

The presented study outlines the fabrication of chitosan (CS)-loaded lanthanum iron oxide (LFO) nanoparticles (CS/LFO) via a simple auto-combustion method combined with ultrasonication. The various prepared x CS/LFOs (x = 100, 200, 300, 400, and 500) were well analyzed with several characterization techniques. The x CS/LFO-modified glassy carbon electrode (GCE) was then utilized for electrochemical tyramine detection. Additionally, the obtained electrochemical response was also compared with the pure constituents. Herein, the numerous electrochemical parameters including the volume of electrocatalyst loaded, pH of solution, and accumulation time were optimized so as to acquire the efficient detection. Under optimum conditions, the 400 CS/LFO-modified GCE exhibited an impressive electrochemical response for tyramine detection. The proposed electrochemical sensor afforded a linear co-relation between the anodic peak current and concentration of tyramine in the range of 0.02–100 μM with the detection limits of 0.6158 μM or 615.8 nM (by the linear sweep voltammetry method) and 0.5814 μM or 581.4 nM (by the differential pulse voltammetry method). Furthermore, the prepared 400 CS/LFO was applied on the screen-printed electrode and its stability was evaluated for a period of 30 days in order to develop a portable electrochemical sensor. The constructed sensor displayed promising stability, repeatability, and reproducibility for tyramine detection. The real-time analysis capability of the introduced sensing platform was evaluated via real sample analysis of various food products including milk, beer, fish, meat, and yoghurt. The prepared sensor afforded desirable recovery rates, demonstrating its practical utility.

A lanthanide-MOF based host–guest intelligent dual-stimulus response platform for naked-eye and ratiometric fluorescence monitoring of food freshness

“…Tyramine (Tyr) is one kind of biogenic amine and is considered an important biomarker for monitoring food spoilage. [1][2][3][4] As a type of organic base containing nitrogen, Tyr is usually generated via the degradation of the corresponding amino acids, and is widely found in various ordinary foods and drinks, such as beef, fish, cheese, and milk. [5][6][7] Excessive intake of Tyr in spoiled foods seriously affects human health, which can cause headache, vomiting, palpitation, chest tightness and even asthma.…”