Fully Inkjet Printing Preparation of a Carbon Dots Multichannel Microfluidic Paper-Based Sensor and Its Application in Food Additive Detection

Abstract

Microfluidic paper-based sensors as a new type of microsample detection technology are widely used in medical diagnosis, environmental monitoring, and food safety testing. Inkjet printing has the advantages of simplicity, speed, flexibility, high resolution, low cost, and efficient mass production and has become one of the most cutting-edge technologies in the manufacture of paper-based sensors. In this work, a fully inkjet printing preparation method was proposed for paper-based sensors, which can achieve high-precision, multichannel, and visual fluorescence detection. Three kinds of fluorescent carbon dots (CDs; r-CDs, b-CDs, and y-CDs) were fabricated into inkjet ink by adding a suitable ratio of solvent, PEG, and surfactant FS3100 to control its viscosity, surface tension, and other influencing factors, obtaining the best-visualized fluorescence response on paper. To optimize the full inkjet printing process of the paper-based sensor, we studied the influence of factors such as the hydrophobic material AKD formula, postprocessing conditions, and the structure of the hydrophilic and hydrophobic channels on the paper-based detection accuracy, and it was found that proper AKD concentration, curing time, and temperature can make AKD fully react with paper-based surface groups and produce more hydrophobic groups on the surface and inside of the filter paper, which can form paper-based microfluidic sensors with clear boundaries and fast transmission speed at low cost and high efficiency. The fabricated sensor is used for the fluorometric determination of vitamin C (AA), NO2 –, and sunset yellow (SY) at the same time, and the limits of visual detection by eyes are 6 mmol/L (NO2 –), 60 μmol/L (SY), and 40 mmol/L (AA). The mechanism of inkjet printing is investigated in detail, which is simple, reliable, and easy to realize mass production and can realize highly sensitive, on-site, and visual detection for food additives.

Structural, rheological, and gelling characteristics of starch‐based materials in context to 3D food printing applications in precision nutrition

“…Adhesive‐coated foods typically use a mixture of sugar and starch powders with water‐ or alcohol‐based adhesives to create macroscopic and decorative 3D structures (Holland, Foster, et al., 2018). The choice of adhesive is critical in the binder jetting printing through trial and error due to a lack of understanding of the basic interactions that make up a good adhesive (Deng et al., 2021). However, the food printed successfully has a rough appearance and needs further processing (Pitayachaval et al., 2018).…”

Paper-based microfluidics in sweat detection: from design to application

“…In terms of chemical modification, covalent chemical modification of paper based on reacting with functional groups in cellulose is the most commonly used method. 56,57 For example, Malancha Gupta et al demonstrated for the first time that solventless initiated chemical vapor deposition can be used for three-dimensional patterning of paper-based microfluidics with a thin layer of hydrophobic photo responsive poly(o-nitro benzyl methacrylate). 58 Hsiu-Yang Tseng et al successfully developed programmable wicking profiles by alternating coated and uncoated zones with a solution composed of potassium alum and animal glue, which is a sizing material used in the fabrication of calligraphy Xuan paper.…”

A Facile Dual‐Emission Ratiometric Carbon‐Dot Fluorescent Probe and Its Application in Portable Chemical Sensors and Water Quality Analysis

“…So far, a variety of instrumental techniques for the detection of Fe 3+ have been established, and analytical techniques include chemiluminescence, atomic absorption spectroscopy, fiber‐optic chemical sensors, [5] voltammetry, and inductively coupled plasma mass spectrometry (ICP‐MS) [6] and so on. These instrument technologies have high accuracy and wide detection range for the detection of Fe 3+ , but the disadvantage is the high price of the instrument and the expensive price of subsequent instrument maintenance, time‐consuming pretreatment and tedious operation methods.…”