Size-Dependent Antibacterial Behavior of Graphene Quantum Dots

2013 ◽  
Author(s):  
Siheng Su ◽  
Carla B. Shelton ◽  
Jingjing Qiu
Keyword(s):  
Quantum Dots ◽  
Surface Chemistry ◽  
Graphene Quantum Dots ◽  
Gel Filtration ◽  
Filtration Method ◽  
E Coli ◽  
Size Dependent ◽  
Mtt Method ◽  
Diphenyltetrazolium Bromide ◽  
Standard Plate

In this study, the antibacterial behavior of differing sized graphene quantum dots (GQDs) was studied. The gram negative bacteria, Escherichia coli (E. coli), were used as the bacteria mode. Different sized GQDs with tunable fluorescent colors were acquired by a gel-filtration method. The size, surface chemistry, and photoluminescence properties of GQDs were characterized, respectively. The viability of GQDs treated bacteria was determined by the standard plate counting method. Moreover, the reactive oxidative species (ROS) level was detected by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) method. The integrality of the bacteria membrane was observed under the scanning electron microscopy (SEM). The experimental results indicated that GQDs demonstrated size-dependent and surface chemistry-dependent antibacterial behaviors. This research provided insightful guidelines in the selection of suitable GQDs for their potential bioapplications.

A Nanoscale Adventure with Silicon: Synthesis, Surface Chemistry, and other Surprises

2015 ◽  
Vol 242 ◽  
pp. 383-390
Author(s):  
Md Hosnay Mobarok ◽  
Tapas K. Purkait ◽  
Jonathan G.C. Veinot
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Surface Chemistry ◽  
Research Group ◽  
Size Dependent ◽  
Earth Abundant ◽  
Potential Applications ◽  
Si Quantum Dots

The preparation and surface chemistry Si quantum dots (SiQDs) are currently an intense focus of research because of their size dependent optical properties and many potential applications. SiQDs offer several advantages over other quantum dots; Si is earth abundant, non-toxic and biocompatible. This account briefly highlights recent advancements made by our research group related to the synthesis, functionalization, surface dependent optical properties and applications of SiQDs.

scholarly journals Conjugation of Carboxylated Graphene Quantum Dots with Cecropin P1 for Bacterial Biosensing Applications

2020 ◽  
Author(s):  
Jonathan Bruce ◽  
Jude Clapper
Keyword(s):  
Quantum Dots ◽  
Structural Modification ◽  
Light Emission ◽  
Limit Of Detection ◽  
Graphene Quantum Dots ◽  
Strong Light ◽  
E Coli ◽  
Cecropin P1 ◽  
Compact Field ◽  
Test Kit

<p>Quantum dots have proven to be strong candidates for biosensing applications in recent years, due to their strong light emission properties and their ability to be modified with a variety of functional groups for the detection of different analytes. Here, we investigate the use of conjugated carboxylated graphene quantum dots (CGQDs) for the detection of <i>E. coli</i>, using a biosensing procedure that focuses on measuring changes in fluorescence quenching. We have also further developed this biosensing assay into a compact, field-deployable test kit focused on rapidly measuring changes in absorbance to determine bacterial concentration. Our CGQDs were conjugated with cecropin P1, a naturally-produced antibacterial peptide that facilitates the attachment of CGQDs to <i>E. coli</i> cells. We also confirm the structural modification of these conjugated CGQDs in addition to analyzing their optical characteristics. Our findings have the potential to be used in situations where rapid, reliable detection of bacteria in liquids, such as drinking water, is required, especially given our biosensor’s relatively low observed limit of detection (LOD).</p><br>

scholarly journals Graphene Quantum Dots as Flourishing Nanomaterials for Bio-Imaging, Therapy Development, and Micro-Supercapacitors

Micromachines ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 866
Author(s):  
Merve Kortel ◽  
Bhargav D. Mansuriya ◽  
Nicole Vargas Santana ◽  
Zeynep Altintas
Keyword(s):  
Quantum Dots ◽  
Structural Properties ◽  
Edge Effects ◽  
Quantum Confinement ◽  
Review Paper ◽  
Graphene Quantum Dots ◽  
Heteroatom Doping ◽  
Size Dependent ◽  
Bio Imaging ◽  
Therapy Development

Graphene quantum dots (GQDs) are considerably a new member of the carbon family and shine amongst other members, thanks to their superior electrochemical, optical, and structural properties as well as biocompatibility features that enable us to engage them in various bioengineering purposes. Especially, the quantum confinement and edge effects are giving GQDs their tremendous character, while their heteroatom doping attributes enable us to specifically and meritoriously tune their prospective characteristics for innumerable operations. Considering the substantial role offered by GQDs in the area of biomedicine and nanoscience, through this review paper, we primarily focus on their applications in bio-imaging, micro-supercapacitors, as well as in therapy development. The size-dependent aspects, functionalization, and particular utilization of the GQDs are discussed in detail with respect to their distinct nano-bio-technological applications.

Size-Dependent Structural and Optical Characteristics of Glucose-Derived Graphene Quantum Dots

2013 ◽  
Vol 30 (6) ◽  
pp. 523-531 ◽  
Author(s):  
Libin Tang ◽  
Rongbin Ji ◽  
Xueming Li ◽  
Kar Seng Teng ◽  
Shu Ping Lau
Keyword(s):  
Quantum Dots ◽  
Graphene Quantum Dots ◽  
Optical Characteristics ◽  
Size Dependent

Size-dependent radiative decay processes in graphene quantum dots

2012 ◽  
Vol 101 (16) ◽  
pp. 163103 ◽  
Author(s):  
Sung Kim ◽  
Dong Hee Shin ◽  
Chang Oh Kim ◽  
Soo Seok Kang ◽  
Jong Min Kim ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Radiative Decay ◽  
Graphene Quantum Dots ◽  
Size Dependent

scholarly journals A comparison of purified valyl-transfer ribonucleic acid synthetase from Bacillus stearothermophilus and from Escherichia coli

1974 ◽  
Vol 139 (2) ◽  
pp. 391-398 ◽  
Author(s):  
Susan Wilkinson ◽  
Jeremy R. Knowles
Keyword(s):  
Escherichia Coli ◽  
Gel Electrophoresis ◽  
Bacillus Stearothermophilus ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Binding Constants ◽  
Trna Synthetase ◽  
Subunit Structure ◽  
Filtration Method ◽  
E Coli

The purification of valyl-tRNA synthetase from Bacillus stearothermophilus is described. The protein was greater than 90% homogeneous on polyacrylamide-gel electrophoresis after more than 850-fold purification. It has a molecular weight of 110000, and no evidence was found for the presence of subunit structure. The properties of the purified enzyme were compared with those of purified valyl-tRNA synthetase from Escherichia coli. The thermal stability, pH-stability and dependence of activity on the temperature and pH of the assay are reported. The two enzymes recognize and charge tRNAVal from crude tRNA of the mesophile E. coli and of the thermophile B. stearothermophilus, indiscriminately. The gel-filtration method was extended to measure the binding of tRNA to synthetase directly. Binding constants for tRNAVal to valyl-tRNA synthetase from B. stearothermophilus were determined between 5° and 60°C.

scholarly journals Size-dependent two-photon absorption in circular graphene quantum dots

2016 ◽  
Vol 24 (3) ◽  
pp. 2877 ◽  
Author(s):  
Xiaobo Feng ◽  
Xin Li ◽  
Zhisong Li ◽  
Yingkai Liu
Keyword(s):  
Quantum Dots ◽  
Graphene Quantum Dots ◽  
Photon Absorption ◽  
Two Photon Absorption ◽  
Size Dependent ◽  
Two Photon

One-pot synthesis of sulfur-doped graphene quantum dots as a novel fluorescent probe for highly selective and sensitive detection of lead(ii)

RSC Advances ◽  
2016 ◽  
Vol 6 (74) ◽  
pp. 69977-69983 ◽  
Author(s):  
Shiyue Bian ◽  
Chao Shen ◽  
Hong Hua ◽  
Lin Zhou ◽  
Hailin Zhu ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Quantum Dots ◽  
Surface Chemistry ◽  
Graphene Quantum Dots ◽  
Sensitive Detection ◽  
Monolayer Graphene ◽  
One Pot ◽  
Doped Graphene ◽  
One Step ◽  
The One

A facile strategy was developed for the one-step synthesis of S-GQDs with a monolayer-graphene crystal structure. The change of surface chemistry by S-doping resulted in selective and sensitive detection of Pb2+.

Sign in / Sign up

Export Citation Format

Share Document