A Review of Carbon Dots Produced from Biomass Wastes

The fluorescent carbon dot is a novel type of carbon nanomaterial. In comparison with semiconductor quantum dots and fluorescence organic agents, it possesses significant advantages such as excellent photostability and biocompatibility, low cytotoxicity and easy surface functionalization, which endow it a wide application prospect in fields of bioimaging, chemical sensing, environmental monitoring, disease diagnosis and photocatalysis as well. Biomass waste is a good choice for the production of carbon dots owing to its abundance, wide availability, eco-friendly nature and a source of low cost renewable raw materials such as cellulose, hemicellulose, lignin, carbohydrates and proteins, etc. This paper reviews the main sources of biomass waste, the feasibility and superiority of adopting biomass waste as a carbon source for the synthesis of carbon dots, the synthetic approaches of carbon dots from biomass waste and their applications. The advantages and deficiencies of carbon dots from biomass waste and the major influencing factors on their photoluminescence characteristics are summarized and discussed. The challenges and perspectives in the synthesis of carbon dots from biomass wastes are also briefly outlined.

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A Review on Multifunctional Carbon-Dots Synthesized From Biomass Waste: Design/ Fabrication, Characterization and Applications

Frontiers in Energy Research ◽

10.3389/fenrg.2021.626549 ◽

2021 ◽

Vol 9 ◽

Author(s):

Nurul Kamilah Khairol Anuar ◽

Huey Ling Tan ◽

Ying Pei Lim ◽

Mohamad Sufian So’aib ◽

Noor Fitrah Abu Bakar

Keyword(s):

Carbon Dots ◽

Metal Ion ◽

Large Scale ◽

Raw Materials ◽

Low Cost ◽

Agricultural Waste ◽

Scale Up ◽

Chemical Properties ◽

Biomass Waste ◽

Wide Range

Carbon-Dots (C-Dots) have drawn much attention in recent years owing to their remarkable properties such as high biocompatibility, low toxicity, nano-scale size, and ease of modification with good tuneable photoluminescence performance. These unique properties have led C-Dots to become a promising platform for bioimaging, metal ion sensing and an antibacterial agent. C-Dots can be prepared using the top-down and bottom-up approaches, in which the latter method is commonly used for large scale and low-cost synthesis. C-Dots can be synthesized using sustainable raw materials or green biomass since it is environmentally friendly, in-expensive and most importantly, promotes the minimization of waste production. However, using biomass waste to produce high-quality C-Dots is still a matter of concern waiting for resolution, and this will be the main focus of this review. Fundamental understanding of C-Dots such as structure analysis, physical and chemical properties of C-Dots, various synthesis methodology and type of raw materials used are also discussed and correlated comprehensively. Additionally, factors affecting the bandgap of the C-Dots and the strategies to overcome these shortcomings are also covered. Moreover, formation mechanism of C-Dots focusing on the hydrothermal method, option and challenges to scale up the C-Dots production are explored. It is expected that the great potential of producing C-Dots from agricultural waste a key benefit in view of their versatility in a wide range of applications.

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A binary solvent for the simultaneous Calophyllum oil-resin extraction and purification

Research in Agricultural Engineering ◽

10.17221/30/2018-rae ◽

2019 ◽

Vol 65 (No. 2) ◽

pp. 63-69

Author(s):

Ika Amalia Kartika ◽

Oky Tresia Ordian Bernia ◽

Illah Sailah ◽

Tirto Prakoso ◽

Yohanes Aris Purwanto

Keyword(s):

Raw Materials ◽

Low Cost ◽

Acid Value ◽

Biodiesel Production ◽

Oil Yield ◽

Binary Solvent ◽

Renewable Raw Materials ◽

Efficient Energy ◽

Yield And Quality ◽

Extraction And Purification

Sustainable biodiesel production can be realised by the use of a low-cost feedstock, efficient energy and renewable raw materials. The simultaneous Calophyllum oil-resin extraction and its purification using a binary solvent (n-hexane mixed with alcohol) were examined to meet those aspects. The extraction conditions effect was investigated to determine the optimal oil yield and quality. n-Hexane mixed with alcohol was extracted and purified effectively the oil from Calophyllum seeds. The oil yield and its quality were mainly affected by the n-hexane-to-alcohol ratio. The oil yield enhanced as the n-hexane-to-alcohol ratio enlarged from 1:1 to 2.5:1. The acid value and density of the oil improved as the n-hexane-to-alcohol ratio declined from 2.5:1 to 1:1. The n-Hexane-to-alcohol ratio of 2.5:1 provided the best yield (59%) of the oil extracted at 40°C for 5 hours. The oil presented its best quality at 0.893 g·cm<sup>–3</sup> of density, 41.0 mPa·s of viscosity, 8.8 mg KOH·g<sup>–1</sup> of the acid value, 88.3 g per 100 g of the iodine value, < 1% of moisture content and < 0.04% of ash content. The oil also had an inhibitory activity against Staphylococcus aureus.

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A Green and Simple Protocol for Extraction and Application of a Peroxidase-Rich Enzymatic Extract

Methods and Protocols ◽

10.3390/mps3020025 ◽

2020 ◽

Vol 3 (2) ◽

pp. 25

Author(s):

Gonçalo P. Rosa ◽

Maria do Carmo Barreto ◽

Diana C. G. A. Pinto ◽

Ana M. L. Seca

Keyword(s):

Raw Materials ◽

Low Cost ◽

Environmentally Friendly ◽

Chemical Processes ◽

Enzymatic Extract ◽

Renewable Raw Materials ◽

Mild Conditions ◽

Social Expectation ◽

Simple Protocol ◽

Working Parameters

Recently there is a great social expectation that scientists should produce more sustainable and environmentally friendly chemical processes. Within this necessity, biocatalysis presents many attractive features because reactions are often performed in water, under mild conditions, the catalyst is biodegradable and can be obtained from renewable raw materials. In this work, we propose a simple, rapid and low-cost method for the preparation and application of an enzymatic extract from turnip root. The protocol described includes (1) the preparation of the enzymatic extract, (2) the procedure for the assessment of the more favorable working parameters (temperature, pH) and (3) the methodology for the application of the extract as the catalyst for biotransformation reactions. We anticipate that the protocol in this research will provide a simple way for obtaining an enzymatic extract which can operate efficiently under mild conditions and can effectively catalyze the biotransformation of simple phenols.

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Carboxyl-Rich Carbon Dots as Highly Selective and Sensitive Fluorescent Sensor for Detection of Fe3+ in Water and Lactoferrin

Polymers ◽

10.3390/polym13244317 ◽

2021 ◽

Vol 13 (24) ◽

pp. 4317

Author(s):

Xinxin Wang ◽

Yanan Zhao ◽

Ting Wang ◽

Yan Liang ◽

Xiangzhong Zhao ◽

...

Keyword(s):

Carbon Dots ◽

Density Functional ◽

Limit Of Detection ◽

Fluorescent Sensor ◽

Low Cost ◽

Hydrothermal Process ◽

Blue Emission ◽

Disease Diagnosis ◽

Obvious Effect ◽

Physiological Processes

As lactoferrin (LF) plays an essential role in physiological processes, the detection of LF has attracted increasing attention in the field of disease diagnosis. However, most current methods require expensive equipment, laborious pretreatment, and long processing time. In this work, carboxyl-rich carbon dots (COOH-CDs) were facilely prepared through a one-step, low-cost hydrothermal process with tartaric acid as the precursor. The COOH-CDs had abundant carboxyl on the surface and showed strong blue emission. Moreover, COOH-CDs were used as a fluorescent sensor toward Fe3+ and showed high selectivity for Fe3+ with the limit of detection (LoD) of 3.18 nM. Density functional theory (DFT) calculations were performed to reveal the mechanism of excellent performance for Fe3+ detection. Meanwhile, COOH-CDs showed no obvious effect on lactobacillus plantarum growth, which means that COOH-CDs have good biocompatibility. Due to the nontoxicity and excellent detection performance for Fe3+, COOH-CDs were employed as a fluorescent sensor toward LF and showed satisfying performance with an LoD of 0.776 µg/mL, which was better than those of the other methods.

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Carbon Dots as a Sustainable New Platform for Organic Light Emitting Diode

Coatings ◽

10.3390/coatings11010005 ◽

2020 ◽

Vol 11 (1) ◽

pp. 5

Author(s):

Paola Lagonegro ◽

Umberto Giovanella ◽

Mariacecilia Pasini

Keyword(s):

Carbon Dots ◽

Raw Materials ◽

Light Emitting Diode ◽

Renewable Raw Materials ◽

Light Emitting ◽

Light Emitting Devices ◽

Organic Light Emitting Diode ◽

Organic Light ◽

The Impact ◽

Safe By Design

Over the past 10 years, carbon dots (CDs) synthesized from renewable raw materials have received considerable attention in several fields for their unique photoluminescent properties. Moreover, the synthesis of CDs fully responds to the principles of circular chemistry and the concept of safe-by-design. This review will focus on the different strategies for incorporation of CDs in organic light-emitting devices (OLEDs) and on the study of the impact of CDs properties on OLED performance. The main current research outcomes and highlights are summarized to guide users towards full exploitation of these materials in optoelectronic applications.

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Collagen–Alginate Composite Hydrogel: Application in Tissue Engineering and Biomedical Sciences

Polymers ◽

10.3390/polym13111852 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1852

Author(s):

Tingyu Hu ◽

Amy C. Y. Lo

Keyword(s):

Tissue Engineering ◽

Cell Attachment ◽

Low Cost ◽

3D Culture ◽

Brown Seaweed ◽

Biomedical Sciences ◽

Cell Binding ◽

Wide Availability ◽

Low Cytotoxicity ◽

Bioactive Agents

Alginate (ALG), a polysaccharide derived from brown seaweed, has been extensively investigated as a biomaterial not only in tissue engineering but also for numerous biomedical sciences owing to its wide availability, good compatibility, weak cytotoxicity, low cost, and ease of gelation. Nevertheless, alginate lacks cell-binding sites, limiting long-term cell survival and viability in 3D culture. Collagen (Col), a major component protein found in the extracellular matrix (ECM), exhibits excellent biocompatibility and weak immunogenicity. Furthermore, collagen contains cell-binding motifs, which facilitate cell attachment, interaction, and spreading, consequently maintaining cell viability and promoting cell proliferation. Recently, there has been a growing body of investigations into collagen-based hydrogel trying to overcome the poor mechanical properties of collagen. In particular, collagen–alginate composite (CAC) hydrogel has attracted much attention due to its excellent biocompatibility, gelling under mild conditions, low cytotoxicity, controllable mechanic properties, wider availability as well as ease of incorporation of other biomaterials and bioactive agents. This review aims to provide an overview of the properties of alginate and collagen. Moreover, the application of CAC hydrogel in tissue engineering and biomedical sciences is also discussed.

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Inclusion of Lignocellulosic Fibers in Plastic Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.600.442 ◽

2014 ◽

Vol 600 ◽

pp. 442-446

Author(s):

Ricardo Gabriel de Almeida Mesquita ◽

Gustavo H. Denzin Tonoli ◽

Rafael Farinassi Mendes ◽

Antônia Amanda da Silva César ◽

Lina Bufalino ◽

...

Keyword(s):

Raw Materials ◽

Unsaturated Polyester ◽

Low Cost ◽

Glass Fibers ◽

Physical And Mechanical Properties ◽

Plant Fibers ◽

Lignocellulosic Fiber ◽

Plastic Composites ◽

Wide Availability ◽

Feasible Alternative

Solutions for the production of sustainable plastics have motivated the scientific community to search for new alternatives for the replacement of raw materials from non-renewable sources such as glass fibers. Therefore, plant fibers appear to be a feasible alternative, since they present low cost, suitable mechanical strength, wide availability, as well as are renewable. This work aimed to evaluate the replacement of glass fibers by lignocellulosic fiber in plastic composites used in civil construction sectors. The resin used was ortho unsaturated polyester. Three plant fibers were tested (sugar cane bagasse, eucalypt and pine) with and without chemical modification. The chemical modifications were performed with sodium hydroxide. The composites were evaluated by their physical and mechanical properties. The initial results showed the potential of using plant fiber in the production of fiber-reinforced plastic composites. Keywords: plant fibers, residues, polyester resin

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Microwave-assisted conversion of palm kernel shell biomass waste to photoluminescent carbon dots

Scientific Reports ◽

10.1038/s41598-020-78322-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Wei Lun Ang ◽

Cheldclos A. L. Boon Mee ◽

Nonni Soraya Sambudi ◽

Abdul Wahab Mohammad ◽

Choe Peng Leo ◽

...

Keyword(s):

Heavy Metal ◽

Metal Ions ◽

Carbon Dots ◽

Heavy Metal Ions ◽

Low Cost ◽

Palm Kernel ◽

Photoluminescence Intensity ◽

Biomass Waste ◽

Palm Kernel Shell ◽

Irradiation Period

AbstractIn the present work, palm kernel shell (PKS) biomass waste has been used as a low-cost and easily available precursor to prepare carbon dots (CDs) via microwave irradiation method. The impacts of the reacting medium: water and diethylene glycol (DEG), and irradiation period, as well as the presence of chitosan on the CDs properties, have been investigated. The synthesized CDs were characterized by several physical and optical analyses. The performance of the CDs in terms of bacteria cell imaging and copper (II) ions sensing and removal were also explored. All the CDs possessed a size of 6–7 nm in diameter and the presence of hydroxyl and alkene functional groups indicated the successful transformation of PKS into CDs with carbon core consisting of C = C elementary unit. The highest quantum yield (44.0%) obtained was from the CDs synthesised with DEG as the reacting medium at irradiation period of 1 min. It was postulated that the high boiling point of DEG resulted in a complete carbonisation of PKS into CDs. Subsequently, the absorbance intensity and photoluminescence intensity were also much higher compared to other precursor formulation. All the CDs fluoresced in the bacteria culture, and fluorescence quenching occurred in the presence of heavy metal ions. These showed the potential of CDs synthesised from PKS could be used for cellular imaging and detection as well as removal of heavy metal ions.

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Starch-Based Carbon Dots for Nitrite and Sulfite Detection

Frontiers in Chemistry ◽

10.3389/fchem.2021.782238 ◽

2021 ◽

Vol 9 ◽

Author(s):

Panyong Wang ◽

Yan Zhang ◽

Yulu Liu ◽

Xinpei Pang ◽

Pai Liu ◽

...

Keyword(s):

Charge Transfer ◽

Human Health ◽

Efficient Method ◽

Redox Reaction ◽

Carbon Dots ◽

Environmental Science ◽

Raw Materials ◽

Turn On ◽

Low Cytotoxicity ◽

Fluorescence Turn On

Nitrite and sulfite play important roles in human health and environmental science, so it is desired to develop a facile and efficient method to evaluate NO2- and SO32- concentrations. In this article, the use of green alternatives with the potential of multi-functionality has been synthesized to detect nitrite and sulfite based on fluorescent probe. The carbon dots (CDs) with starch as only raw materials show fluorescence turn “on-off-on” response towards NO2- and SO32- with the limits of detection of 0.425 and 0.243 μМ, respectively. Once nitrite was present in the solution, the fluorescence of CDs was quenched rapidly due to the charge transfer. When sulfite was introduced, the quenching fluorescence of CDs was effectively recovered because of the redox reaction between NO2- and SO32-, and thus providing a new way for NO2- and SO32- detection. Owing to their excellent analytical characteristics and low cytotoxicity, the “on-off-on” sensor was successfully employed for intracellular bioimaging of NO2- and SO32-.

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Chemistry Based on Renewable Raw Materials: Perspectives for a Sugar Cane-Based Biorefinery

Enzyme Research ◽

10.4061/2011/654596 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Murillo Villela Filho ◽

Carlos Araujo ◽

Alfredo Bonfá ◽

Weber Porto

Keyword(s):

Chemical Industry ◽

Sugar Cane ◽

Raw Materials ◽

Low Cost ◽

Raw Material ◽

Biobased Products ◽

Chemical Production ◽

Renewable Raw Materials ◽

Wide Range ◽

Sugar Mills

Carbohydrates are nowadays a very competitive feedstock for the chemical industry because their availability is compatible with world-scale chemical production and their price, based on the carbon content, is comparable to that of petrochemicals. At the same time, demand is rising for biobased products. Brazilian sugar cane is a competitive feedstock source that is opening the door to a wide range of bio-based products. This essay begins with the importance of the feedstock for the chemical industry and discusses developments in sugar cane processing that lead to low cost feedstocks. Thus, sugar cane enables a new chemical industry, as it delivers a competitive raw material and a source of energy. As a result, sugar mills are being transformed into sustainable biorefineries that fully exploit the potential of sugar cane.

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