Quantum dot-modified paper-based assay for glucose screening

Abstract

A simple and inexpensive method to fabricate a colloidal CdSe/ZnS quantum dots-modified paper-based assay for glucose is herein reported. The circular paper sheets were uniformly loaded and displayed strong fluorescence under a conventional hand-held UV lamp (365 nm). The assay is based on the use of glucose oxidase enzyme (GOx), which impregnated the paper sheets, producing H2O2 upon the reaction with the glucose contained in the samples. After 20 min of exposure, the fluorescence intensity changed due to the quenching caused by H2O2. To obtain a reading, the paper sheets were photographed under 365 nm excitation using a digital camera. Several parameters, including the amount of QD, sample pH, and amount of GOx were optimized to maximize the response to glucose. The paper-based assay showed a sigmoidal-shaped response with respect to the glucose concentration in the 5–200 mg·dL−1 range (limit of detection of 5 μg·dL−1), demonstrating their potential use for biomedical applications.

Synthesis of CuNP-modified carbon electrodes obtained by pyrolysis of paper

“…This interest is driven by the unique structure, high surface area, good mechanical [1] and thermal stability, and unusual optical, chemical, magnetic, and catalytic properties of these nanostructures [2]. The great diversity of composition, shape, and size of metallic NPs [3, 4] have also allowed researchers exploring their applications in related fields, such as catalysis [5], optical devices [6], and electronic components [7]. Following these developments, the modification of surfaces with metallic nanomaterials is one of the most important strategies to improve the performance of electrochemical sensors [8-11].…”

A Review on Microfluidic Paper-Based Analytical Devices for Glucose Detection

“…Except for the conventional colorimetric and electrochemical techniques for glucose detection, there are some other techniques, such as luminescence [126], fluorescence [127], calorimetric [128], mass spectrum (MS) [129] and surface-enhanced Raman spectroscopy (SERS) [130] applied to μPADs for rapid glucose diagnostics. Chen et al [126] developed a turn-on paper-based phosphorescence device using Ir-Zn e , a kind of luminescence sensing material, composited with GOx with layer-by-layer technique.…”

“…The linear calibration range was from 0.05 to 8.0 mM with a correlation coefficient of 0.9956 and the LOD was 0.05 mM. Durán et al [127] utilized colloidal CdSe/ZnS quantum dots (Q-dots) to produce an optical paper-based device for glucose detection. Paper loaded with Q-dots would display strong fluorescence under a UV lamp.…”

A capillary electrophoresis method to explore the self‐assembly of a novel polypeptide ligand with quantum dots

“…Although there are different types of materials (such as quantum dots [QDs], polymers, hydrogels, peptides, and mesoporous silica, etc.) that are suited for various biomedical applications , the development of QDs‐based sensors has become a very popular research area. Understandably, the performance of these methods is highly dependent on the development of new ligands for binding with QDs .…”