Enhancing the chemiluminescence intensity of a KMnO₄ formaldehyde system for estimating the total phenolic content in honey samples using a novel nanodroplet mixing approach in a microfluidics platform

Abstract

A novel mixing approach was utilized with a highly sensitive chemiluminescence (CL) method to determine the total phenolic content (TPC) in honey samples using an acidic potassium permanganate-formaldehyde system. The mixing approach was based on exploiting the mixing efficiency of nanodroplets generated in a microfluidic platform. Careful optimization of the instrument setup and various experimental conditions were employed to obtain excellent sensitivity. The mixing efficiency of the droplets was compared with the CL signal intensity obtained using the common serpentine chip design, with both approaches using at a total flow rate of 15 μl min ; the results showed that the nanodroplets provided 600% higher CL signal intensity at this low flow rate. Using the optimum conditions, calibration equations, limits of detection (LOD) and limits of quantification (LOQ) for gallic acid (GA), caffeic acid (CA), kaempferol (KAM), quercetin (QRC) and catechin (CAT) were obtained. The LOD ranged from 6.2 ppb for CA to 11.0 ppb for QRC. Finally, the method was applied for the determination of TPC in several local and commercial honey samples.

Paper-based Chemiluminescence Device with Co-Fe Nanocubes for Sensitive Detection of Caffeic Acid

“…It is common that most of CL systems need the involvement of extra oxidants, such as H2O2 22 and KMnO4. 20 However, in the work no extra oxidant was added in the luminol-Co-Fe PBA NCs system. Then we deduced that dissolved oxygen was participated in this system.…”

“…19 Kefalas' team studied the antioxidant activity of four kinds of antioxidants mixtures (uncliptin, ascorbic acid, catechin, CA) under different mole ratio with luminol-Co(Ⅱ)-EDTA system. 19 KMnO4-CH2O CL system 20 and Ce(Ⅳ)-Rh6G CL 21 system have been developed for the determination of PCs in food. Microfluidic device 22 was used with NaHCO3-H2O2-Co 2+ CL system to detect the antioxidants (gallic acid, catechin, CA and rutin) by inhibiting effect in honey and fruit.…”

Metal–Organic Framework Loaded by Rhodamine B As a Novel Chemiluminescence System for the Paper-Based Analytical Devices and Its Application for Total Phenolic Content Determination in Food Samples

“…Simple, rapid, and low-cost optical sensors have been accepted as useful methods for the on-site determination of PCs. − The main attention has recently focused on the chemiluminescence (CL) techniques, − which provide exceptional advantages, including quite simple instrumentation, broad linear ranges, and relatively high selectivity, as well as great sensitivity and excellent detection limits. On the other hand, nanomaterial-assisted CL systems have successfully progressed in recent decays to further improve the classic CL systems and get the best detection sensitivities .…”