Citation: Yang, H.; Wei, Y.; Yan, X.;
Nie, C.; Sun, Z.; Hao, L.; Su, X.
High-Efficiency Utilization of Waste
Tobacco Stems to Synthesize Novel
Biomass-Based Carbon Dots for
Precise Detection of Tetracycline
Antibiotic Residues. Nanomaterials
2022, 12, 3241. https://doi.org/
10.3390/nano12183241
Academic Editor: Laura Canesi
Received: 20 August 2022
Accepted: 13 September 2022
Published: 18 September 2022
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Article
High-Efficiency Utilization of Waste Tobacco Stems to
Synthesize Novel Biomass-Based Carbon Dots for Precise
Detection of Tetracycline Antibiotic Residues
Hui Yang
1,2,3
, Yunlong Wei
4
, Xiufang Yan
5
, Chao Nie
4
, Zhenchun Sun
2
, Likai Hao
1,
* and Xiankun Su
2,
*
1
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry,
Chinese Academy of Sciences, Guiyang 550081, China
2
Guizhou Academy of Tobacco Science, Guiyang 550081, China
3
University of Chinese Academy of Sciences, Beijing 100049, China
4
School of Food & Biological Engineering, Key Laboratory for Agricultural Products Processing
of Anhui Province, Hefei University of Technology, Hefei 230009, China
5
Key Laboratory of Tobacco Quality Research of Guizhou Province, College of Tobacco Science,
Guizhou University, Guiyang 550025, China
* Correspondence: haolikai@mail.gyig.ac.cn (L.H.); xiankunsu@163.com (X.S.)
Abstract:
Recycling waste biomass into valuable products (e.g., nanomaterials) is of considerable
theoretical and practical significance to achieve future sustainable development. Here, we propose
a one-pot hydrothermal synthesis route to convert waste tobacco stems into biomass-based N, S-
codoped carbon dots (C
−
dots) with the assistance of carbon black. Unlike most of the previously
reported luminescent C
−
dots, these biomass-based C
−
dots showed a satisfactory stability, as well
as an excitation-independent fluorescence emission at ~520 nm. Furthermore, they demonstrated
a pH-dependent fluorescence emission ability, offering a scaffold to design pH-responsive assays.
Moreover, these as-synthesized biomass-based C
−
dots exhibited a fluorescence response ability
toward tetracycline antibiotics (TCs, e.g., TC, CTC, and OTC) through the inner filter effect (IFE),
thereby allowing for the establishment a smart analytical platform to sensitively and selectively
monitor residual TCs in real environmental water samples. In this study, we explored the conversion
of waste tobacco stems into sustainable biomass-based C
−
dots to develop simple, efficient, label-free,
reliable, low-cost, and eco-friendly analytical platforms for environmental pollution traceability
analysis, which might provide a novel insight to resolve the ecological and environmental issues
derived from waste tobacco stems.
Keywords:
waste tobacco stems; biomass-based C
−
dots; tetracycline antibiotics; inner filter effect;
environmental pollution traceability analysis
1. Introduction
Recently, making full use of waste biomass to produce valuable products has become
an important way to achieve green and sustainable development, in line with the global
consensus [
1
]. Driven by this motivation, a variety of biomass-derived nanomaterials
have emerged and are widely used in biological/chemical sensing [
2
–
7
]. Among them,
biomass-based carbon dots (C
−
dots), a promising fluorescent carbon-based nanomaterial,
have been widely developed for applications such as environmental pollution traceability
analysis, food safety assessment, bioimaging, fluorescent ink, photocatalysis, etc., owing to
their unique optical properties, low cost, water solubility, high stability, biocompatibility,
and eco-friendliness [
8
–
10
]. Until now, the reported biobased C
−
dots have been primarily
derived from the biomass-related precursors of tree leaves [
11
,
12
], corn stalk shells [
13
,
14
],
peanut shells [
15
], coffee [
16
], capsicum [
17
], and watermelon peel through various thermal
synthesis techniques [
18
], but little attention has been focused on employing waste tobacco
stems as a biomass
−
related precursor to synthesize efficient and green biomass-based
Nanomaterials 2022, 12, 3241. https://doi.org/10.3390/nano12183241 https://www.mdpi.com/journal/nanomaterials
