Microfluidic Detection Platform for Determination of Ractopamine in Food.

A novel microfluidic ractopamine (RAC) detection platform consisting of a microfluidic RAC chip and a smart analysis device is proposed for the determination of RAC concentration in meat samples. This technology utilizes gold nanoparticles (AuNPs) modified with glutamic acid (GLU) and polyethyleneimine (PEI) to measure RAC concentration in food products. When RAC is present, AuNPs aggregate through hydrogen bonding, causing noticeable changes in their optical properties, which are detected using a self-built UV-visible micro-spectrophotometer.

Microfluidic Distillation System for Separation of Propionic Acid in Foods.

A microfluidic distillation system is proposed to facilitate the separation and subsequent determination of propionic acid (PA) in foods. The system comprises two main components: (1) a polymethyl methacrylate (PMMA) micro-distillation chip incorporating a micro-evaporator chamber, a sample reservoir, and a serpentine micro-condensation channel; and (2) and a DC-powered distillation module with built-in heating and cooling functions. In the distillation process, homogenized PA sample and de-ionized water are injected into the sample reservoir and micro-evaporator chamber, respectively, and the chip is then mounted on a side of the distillation module.

Finger pump microfluidic detection system for methylparaben detection in foods.

A novel assay platform consisting of a finger pump microchip (FPM) and a WiFi-based analytical detection platform is presented for measuring the concentration of methylparaben (MP) in commercial foods. In the presented approach, a low quantity (5 μL) of distilled food sample is dripped onto the FPM and undergoes a modified Fenton reaction at a temperature of 40 °C to form a green-colored complex. The MP concentration is then determined by measuring the color intensity (RGB) of the reaction complex using APP software (self-written) installed on a smartphone.

Light-shading reaction microfluidic PMMA/paper detection system for detection of cyclamate concentration in foods.

Cyclamate is an artificial sweetener with high sweetness and low calories, and is a common sugar substitute for weight control and diabetic patients. However, excessive cyclamate consumption is associated with various health disorders, and hence it is prohibited as a food additive in many countries around the world. The current research proposes a light-shading reaction microfluidic PMMA/paper detection (MPD) system for determining the cyclamate concentration in food.

Antioxidant Activity and Inhibitory Effects of Black Rice Leaf on the Proliferation of Human Carcinoma Cells.

The leaves of black rice, well-known as postharvest agricultural waste, contain a rich source of antioxidants with multiple benefits for human health. In the present study, the ethyl acetate fraction obtained from black rice leaf was separated into five subfractions using Sephadex LH-20 column chromatography, and their antioxidant and anticancer activities were investigated. The results revealed that among all the subfractions, subfraction 5 (Sub5) showed the highest total phenolic and flavonoid values.

Evaluation of Phytochemical Contents and In Vitro Antioxidant, Anti-Inflammatory, and Anticancer Activities of Black Rice Leaf ( L.) Extract and Its Fractions.

Black rice leaves ( L.) are a major part of rice straw left in open fields after rice harvest as agricultural waste. In this study, crude ethanolic extract (CEE) and various solvent fractions (hexane (Hex), ethyl acetate (EtOAc), -butanol (-BuOH), and aqueous fractions) of black rice leaves were investigated for their bioactive compound contents as well as antioxidant, anti-inflammatory, and anticancer activities.

Microfluidic colorimetric analysis system for sodium benzoate detection in foods.

Sodium benzoate (SBA) is a widely-used additive for preventing food spoilage and deterioration and extending the shelf life. However, the concentration of SBA must be controlled under safe regulations to avoid damaging human health. Accordingly, this study proposes a microfluidic colorimetric analysis (MCA) system composing of a wax-printed paper-microchip and a self-made smart analysis equipment for the concentration detection of SBA in common foods and beverages.

Multifunctional microchip-based distillation apparatus II - Aerated distillation for sulfur dioxide detection.

A multifunctional microchip-based distillation apparatus is presented for the distilled of sulfur dioxide (SO) in food products. The microchip is fabricated on poly(methyl methacrylate) (PMMA) substrates, and comprises a sample zone, a buffer zone, a serpentine distillation column, and a collection zone. In the process, the sample is introduced into the sample zone and is heated under carefully controlled temperature and time conditions.

Multifunctional microchip-based distillation apparatus I - Steam distillation for formaldehyde detection.

A multifunctional microchip-based distillation apparatus for distilling and detecting formaldehyde (CHO) in food products is developed. The presented apparatus comprises a disposable microchip, a steam supply system, and a recirculating cooling water supply. The microchip is formed on PMMA substrates by laser ablation and includes a sample zone, a flash distillation zone, a cooling zone, a condensation zone, and a collection zone.

A PET/paper chip platform for high resolution sulphur dioxide detection in foods.

A convenient assay platform comprising a PET/paper chip (PP-chip) and a smart analytical device is developed for detection of sulphur dioxide (SO) concentration. In the presented approach, the distilled SO solution is dropped onto the detection region of the PP-chip and undergoes a reaction with an acid-based reagent. The resulting color variation is analyzed through a high-resolution camera (CMOS) and the reacted image is processed by a RGB (red, green and blue) analytical app installed on a smartphone.

Microfluidic paper-based chip platform for benzoic acid detection in food.

An integrated microfluidic platform comprising a microfluidic paper-based analytical device (µPAD) and a portable detection system is proposed for the concentration detection of benzoic acid via Janovsky reaction theory. In the proposed approach, the reaction zone of the µPAD is implanted with 5 N sodium hydroxide and dried at 30 °C for 20 min. The benzoic acid sample is derived to 3,5-Dinitrobenzoic acid using KNO and HSO at 40 °C for 40 min and is then dripped on the reaction zone of the µPAD.

Microfluidic distillation chip for methanol concentration detection.

An integrated microfluidic distillation system is proposed for separating a mixed ethanol-methanol-water solution into its constituent components. The microfluidic chip is fabricated using a CO2 laser system and comprises a serpentine channel, a boiling zone, a heating zone, and a cooled collection chamber filled with de-ionized (DI) water. In the proposed device, the ethanol-methanol-water solution is injected into the microfluidic chip and driven through the serpentine channel and into the collection chamber by means of a nitrogen carrier gas.