scholarly journals Ultrasensitive Detection of Tetracycline Using Boron and Nitrogen Co-Doped Graphene Quantum Dots from Natural Carbon Source as the Paper-Based Nanosensing Probe in Difference Matrices

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1883
Author(s):  
Hai Linh Tran ◽  
Win Darmanto ◽  
Ruey-An Doong

Herein, the boron and nitrogen co-doped 0-dimensional graphene quantum dots (B,N-GQDs) with high quantum yield (QY) were synthesized via microwave-assisted hydrothermal method at 170 °C for 20 min using fresh passion fruit juice and boric acid as the starting materials. The 3–6 layers of B,N-GQDs with mean particle size of 9 ± 1 nm were then used for ultra-sensitive and selective detection of tetracycline in aqueous and biological media. The hybridization of boron and nitrogen atoms into the GQD structures increases the intensity of electronegative, resulting in the enhancement of QY to 50 ± 1%. The B,N-GQDs show their excellent analytical performance on tetracycline determination after 2 min of reaction under an optimal condition at pH 5. The linear range of 0.04–70 µM and with limits of detection (LOD) of 1 nM in phosphate buffer saline (PBS), 1.9 nM in urine and 2.2 nM in human serum are obtained. Moreover, the high selectivity of tetracycline by B,N-GQDs over the other 23 interferences is observed. The π-π interaction and electron donor-acceptor principle play pivotal roles in enhancing the ultra-sensitivity and selectivity of B,N-GQDs toward TC detection. Moreover, the B, N-GQD based paper nanosensor exhibits an excellent analytical performance on visual detection of 0.1–30 µM TC in human serum. Results of this study clearly indicate the feasibility of synthesis of B,N-GQDs derived from passion fruit juice for ultrasensitive tetracycline detection, which can open an avenue to use natural products for the preparation of environmentally benign and biocompatible carbon nanomaterials for highly sensitive detection of drugs, antibiotics, organic compounds and biomarkers.

Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 789
Author(s):  
Shih-Fu Ou ◽  
Ya-Yun Zheng ◽  
Sin-Jen Lee ◽  
Shyi-Tien Chen ◽  
Chien-Hui Wu ◽  
...  

Graphene quantum dots, carbon nanomaterials with excellent fluorescence characteristics, are advantageous for use in biological systems owing to their small size, non-toxicity, and biocompatibility. We used the hydrothermal method to prepare functional N-doped carbon quantum dots (N-CQDs) from 1,3,6-trinitropyrene and analyzed their ability to fluorescently stain various bacteria. Our results showed that N-CQDs stain the cell septa and membrane of the Gram-negative bacteria Escherichia coli, Salmonellaenteritidis, and Vibrio parahaemolyticus and the Gram-positive bacteria Bacillus subtilis, Listeria monocytogenes, and Staphylococcus aureus. The optimal concentration of N-CQDs was approximately 500 ppm for Gram-negative bacteria and 1000 ppm for Gram-positive bacteria, and the exposure times varied with bacteria. N-Doped carbon quantum dots have better light stability and higher photobleaching resistance than the commercially available FM4-64. When excited at two different wavelengths, N-CQDs can emit light of both red and green wavelengths, making them ideal for bioimaging. They can also specifically stain Gram-positive and Gram-negative bacterial cell membranes. We developed an inexpensive, relatively easy, and bio-friendly method to synthesize an N-CQD composite. Additionally, they can serve as a universal bacterial membrane-staining dye, with better photobleaching resistance than commercial dyes.


2017 ◽  
Vol 5 (31) ◽  
pp. 6300-6306 ◽  
Author(s):  
Lin Cao ◽  
Xiangqing Li ◽  
Lixia Qin ◽  
Shi-Zhao Kang ◽  
Guodong Li

A new class of Cyt c detection fluorescence sensor based on graphene quantum dots supported by graphene oxide has been facilely developed. The sensor shows a high sensitivity and selectivity for Cyt c detection, and further exhibits favorable intracellular imaging in A549 cells.


2021 ◽  
Author(s):  
Md. Farhan Naseh ◽  
Neelam Singh ◽  
Jamilur R. Ansari ◽  
Ashavani Kumar ◽  
Tapan Sarkar ◽  
...  

Abstract Here, we report functionalized graphene quantum dots (GQDs) for the optical detection of arsenic at room temperature. GQDs with the fluorescence of three fundamental colors (red, green, and blue) were synthesized and functionally capped with L-cysteine (L-cys) to impart selectively towards As (III) by exploiting the affinity of L-cys towards arsenite. The optical characterization of GQDs was carried out using UV-Vis absorption spectroscopy, Fourier transform infrared spectroscopy, and fluorescence spectrometry and the structural characterizations were performed using transmission electron microscopy. The fluorescence results showed instantaneous quenching in intensity when the GQDs came in contact with As (III) for all test concentrations over a range from 0.025 ppb to 25 ppb, which covers the permissible limit of arsenic in drinking water. The experimental results suggested excellent sensitivity and selectivity towards As (III).


2021 ◽  
Author(s):  
Bingyang Li ◽  
Xiao Xiao ◽  
Menglei Hu ◽  
Yanxin Wang ◽  
Yiheng Wang ◽  
...  

2020 ◽  
Vol 4 (2) ◽  
pp. 507-516 ◽  
Author(s):  
Wissuta Boonta ◽  
Chanon Talodthaisong ◽  
Suchinda Sattayaporn ◽  
Chiraporn Chaicham ◽  
Anusak Chaicham ◽  
...  

A highly sensitive and selective fluorescence sensor using N,S-GQDs for the detection of Co2+ within 3 minutes.


Sign in / Sign up

Export Citation Format

Share Document