Nicotinamide-Functionalized Carbon Quantum Dot as New Sensing Platform for Portable Quantification of Vitamin B12 in Fluorescence, UV–Vis and Smartphone Triple Mode

Abstract

Development of an e cient, portable and simple nanosensor-based systems with reliable analytical performance for on-site monitoring of vitamin B12 (VB12) are still major problems and a challenging work for quality control of manufacturers. Herein, a new uorescence, UV-Vis and smartphone triple mode nanosensors were designed for the simultaneous detection of VB12 with high sensitivity and accuracy. A novel nanosensor was synthesized through nicotinamide-functionalizing on carbon quantum dot (NA-CQDs) by an one-step microwave-assisted method with green approaches. The NA-CQDs as new nanosensor showed excellent uorescence properties and wide linear ranges from 0.1-60 µM with the detection limits of 31.7 nM. Moreover, color changes of NA-CQDs induced by the VB12 could also be detected by UV-Vis spectrophotometer and inhouse-developed application installed on smartphone as a signal reader, simultanusly. The Red, Green and Blue (RGB) intensities of the colorimetric images of NA-CQDs/VB12 system which taken by smartphone's camera converted into quantitative values by the introduced application. A smartphone-integrated with NA-CQDs as colorimetric sensing platform displays good linear ranges (4.16 to 66.6 µM) for on-site determination of VB12 with detection limit of 1.40 µM.The method was successfully applied in the determination of VB12 in complex pharmaceutical supplement formulations without any sample pre-treatment and matrix interfering effects. The recovery results (96.52-105.10%) which are in agreement with the reference methods, demonstrating the capability of the smartphone-assisted colorimetric sensing platform in many on-site practical applications of quality controls.

Smartphone Platform for Low-Cost Point-of-Care Quantitative Detection of Vitamin B12 Utilizing a Biodegradable Bioplastic Nanocomposite-Based Fluorescence Nanosensor

“…Another benefit is that it is portable, rapid, and easy to grasp quantitative data that can be read even by unskilled workers, which is extremely useful in regions with limited resources. So far, there have been very few published research on smartphone-integrated point-of-care nanosensors for on-site monitoring of vitamin B 12 in pharmaceutical, food, and beverage additives. − …”

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