Synthesis and Cytotoxicity of Luminescent InP Quantum Dots

2009 ◽  
Vol 1241 ◽  
Author(s):  
Yuxuan Wang ◽  
Chai Hoon Quek ◽  
Kam W. Leong ◽  
Jiye Fang
Keyword(s):  
Quantum Dots ◽  
Exchange Process ◽  
Positive Control ◽  
Aqueous System ◽  
Water Soluble ◽  
Cell Viability Assay ◽  
Solution Approach ◽  
Viability Assay ◽  
New Type ◽  
Inp Quantum Dots

AbstractAs a potential biological imaging probe with a long-wavelength of emission, InP quantum dots were prepared via a high-temperature organic solution approach, and successfully transferred into an aqueous system through a ligand-exchange process using various functional surfactants. Photoluminescence and X-ray characterizations confirmed the desired properties of the InP quantum dots. The cytotoxicity of the water-soluble InP quantum dots against phaeochromocytoma PC12 cells as evaluated by the MTS cell viability assay was low relative to a positive control, poly(ethyleneimine). This study suggests a bright potential for this new type of InP quantum dots in bioimaging applications.

Do We have a Satisfactory Cell Viability Assay? Review of the Currently Commercially-Available Assays

2020 ◽  
Vol 17 (1) ◽  
pp. 2-22 ◽  
Author(s):  
Abdel-Baset Halim
Keyword(s):  
Cell Viability ◽  
Data Interpretation ◽  
Positive Control ◽  
Live Cells ◽  
Proof Of Concept ◽  
Cell Viability Assay ◽  
Viability Assay ◽  
Current Cell ◽  
Dying Cells ◽  
Differential Permeability

:Cell-based assays are an important part of the drug discovery process and clinical research. One of the main hurdles is to design sufficiently robust assays with adequate signal to noise parameters while maintaining the inherent physiology of the cells and not interfering with the pharmacology of target being investigated.:A plethora of assays that assess cell viability (or cell heath in general) are commercially available and can be classified under different categories according to their concepts and principle of reactions. The assays are valuable tools, however, suffer from a large number of limitations. Some of these limitations can be procedural or operational, but others can be critical as those related to a poor concept or the lack of proof of concept of an assay, e.g. those relying on differential permeability of dyes in-and-out of viable versus compromised cell membranes. While the assays can differentiate between dead and live cells, most, if not all, of them can just assess the relative performance of cells rather than providing a clear distinction between healthy and dying cells. The possible impact of relatively high molecular weight dyes, used in most of the assay, on cell viability has not been addressed. More innovative assays are needed, and until better alternatives are developed, setup of current cell-based studies and data interpretation should be made with the limitations in mind. Negative and positive control should be considered whenever feasible. Also, researchers should use more than one orthogonal method for better assessment of cell health.

Formation of water soluble wavelength tunable InGaP and InP quantum dots

2016 ◽  
Vol 73 (9) ◽  
pp. 2463-2475 ◽  
Author(s):  
Jong-Sik Moon ◽  
Yichen Liang ◽  
Inhong Kim ◽  
Jin-Woo Oh ◽  
Jeffrey G. Winiarz
Keyword(s):  
Quantum Dots ◽  
Water Soluble ◽  
Wavelength Tunable ◽  
Inp Quantum Dots

A water-soluble tetrazolium salt useful for colorimetric cell viability assay

1999 ◽  
Vol 36 (2) ◽  
pp. 47-50 ◽  
Author(s):  
Hideyuki Tominaga ◽  
Munetaka Ishiyama ◽  
Fumio Ohseto ◽  
Kazumi Sasamoto ◽  
Tomoyuki Hamamoto ◽  
...  
Keyword(s):  
Cell Viability ◽  
Water Soluble ◽  
Tetrazolium Salt ◽  
Cell Viability Assay ◽  
Viability Assay

scholarly journals Bacterial Synthesis of Ternary CdSAg Quantum Dots through Cation Exchange: Tuning the Composition and Properties of Biological Nanoparticles for Bioimaging and Photovoltaic Applications

2020 ◽  
Vol 8 (5) ◽  
pp. 631 ◽  
Author(s):  
Nicolás Órdenes-Aenishanslins ◽  
Giovanna Anziani-Ostuni ◽  
Juan Pablo Monrás ◽  
Alejandra Tello ◽  
Denisse Bravo ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Cation Exchange ◽  
Near Infrared ◽  
Fluorescent Dyes ◽  
Exchange Process ◽  
Water Soluble ◽  
Partial Replacement ◽  
Biological Synthesis ◽  
Bacterial Cells ◽  
First Time

In this study, we introduce a biological method for the production of ternary Quantum Dots (QDs): complex nanostructures with tunable optical and structural properties that utilizes post-synthesis modifications through cation exchange. This versatile in-situ cation exchange method being reported for the first time shows great potential for extending the scope of microbial synthesis. By using this bacterial-based method, we easily synthesize and purify CdS, CdSAg, and Ag2S nanocrystals of a size below 15 nm and with variable morphologies that exhibit fluorescence emissions covering a broad spectral range (from 400 to 800 nm). Energy-dispersive X-ray spectroscopy (EDS) results indicate the partial replacement of Cd2+ by Ag+ when AgNO3 concentration is increased. This replacement produces CdSAg ternary QDs hetero-structures with high stability, fluorescence in the NIR-I (700 - 800 nm), and 36.13% quantum yield. Furthermore, this reaction can be extended for the production of soluble Ag2S nanoparticles (NPs) without any traces of Cd. QDs biosynthesized through this cation exchange process display very low toxicity when tested in bacterial or human cell lines. Biosynthesized ternary hetero-structures were used as red fluorescent dyes to label HeLa cells in confocal microscopy studies, which validates its use in bioimaging applications in the near infrared region. In addition, the application of biologically-produced cadmium NPs in solar cells is reported for the first time. The three biosynthesized QDs were successfully used as photosensitizers, where the CdSAg QDs show the best photovoltaic parameters. Altogether, obtained results validate the use of bacterial cells for the controlled production of nanomaterials with properties that allow their application in diverse technologies. We developed a simple biological process for obtaining tunable Quantum Dots (QDs) with different metal compositions through a cation exchange process. Nanoparticles (NPs) are produced in the extracellular space of bacterial cells exposed to cysteine and CdCl2 in a reaction that depends on S2− generation mediated by cysteine desulfhydrase enzymes and uses cellular biomolecules to stabilize the nanoparticle. Using this extracellular approach, water-soluble fluorescent CdS, CdSAg, and Ag2S Quantum Dots with a tunable emission ranging from 400 to 800 nm were generated. This is the first study reporting the use of microorganisms to produce tunable ternary QDs and the first time that a cation exchange process mediated by cells is described. Obtained results validate the use of biological synthesis to produce NPs with new characteristics and opens a completely new research field related to the use of microorganisms to synthesize complex NPs that are difficult to obtain with regular chemical methods.

scholarly journals Novel Ribosome-inactivating Protein (RIP) Isolated from Trichosanthes dioica Induces Apoptosis in HeLa Cell Line

2021 ◽  
Vol 12 (3) ◽  
pp. 165-169
Author(s):  
T. Ghosh ◽  
◽  
Y. Vashi ◽  
K. Barman ◽  
L. I. Singha ◽  
...  
Keyword(s):  
Hela Cells ◽  
Positive Control ◽  
Early Event ◽  
Anticancer Activities ◽  
Ribosome Inactivating Protein ◽  
Cell Viability Assay ◽  
Ribosome Inactivating Proteins ◽  
Viability Assay ◽  
Trichosanthes Dioica ◽  
Parp 1

Ribosome-inactivating proteins (RIPs) are toxic N-glycosidases that depurinate eukaryotic and prokaryotic rRNAs and thus interrupt protein synthesis during translation. In the present study, a protein of around 32 kDa, supposedly a RIP isolated from Trichosanthes dioica, was assessed for its potential to induce apoptosis in HeLa cells. Cell viability assay was done to measure cell proliferation and survivability. It was observed that cells viability decreased with the increase of decrease in dilution, i.e. when the sample was an undiluted one, the viability decreased drastically and almost came to less than 10%. To further check whether the isolated RIP could induce apoptosis, HeLa cells were treated with the test RIP. Immunoblotting was carried out using PARP poly (ADP-ribose) polymerase (PARP-1), a 113 kDa nuclear enzyme, which is considered a hallmark of cells undergoing apoptosis. HeLa cells were further analyzed for loss of mitochondrial membrane potential with JC-1 dye, which is an early event during apoptosis. Increased PARP breakdown in the RIP treated cells indicates that cells undergoing apoptosis and progressive loss of red J-aggregate fluorescence indicate that the isolated RIP from Trichosanthes dioica induces apoptosis in HeLa cells. The ability of apoptosis induction is comparable to another known RIP from Momordica charantia, which was used as a positive control. Promising results from the present study warrants the isolated RIP to be further explored for anticancer activities.

scholarly journals Preparation and Evaluation of Novel Transfersomes Combined with the Natural Antioxidant Resveratrol

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 600 ◽  
Author(s):  
Pey-Shiuan Wu ◽  
Yu-Syuan Li ◽  
Yi-Ching Kuo ◽  
Suh-Jen Tsai ◽  
Chih-Chien Lin
Keyword(s):  
Production Condition ◽  
Entrapment Efficiency ◽  
Cell Viability Assay ◽  
Liposomal System ◽  
Viability Assay ◽  
Anti Cancer ◽  
New Type ◽  
The Stability ◽  
Preparation And Evaluation

Resveratrol (tran-3,5,4′-trihydroxystibene, RSV) is a kind of polyphenol which has anti-inflammatory, antioxidant, anti-allergy, and anti-cancer properties, as well as being a scavenger of free radicals and preventing cardiovascular diseases. However, it is quite unstable in light, heat, and other conditions, and decays easily due to environmental factors. For these reasons, this study used a new type of carrier, transfersome, to encapsulate RSV. Transfersome consists of phosphatidyl choline (PC) from a liposomal system and non-ionic edge activators (EA). EA are an important ingredient in the formulation of transfersome; they can enhance the flexibility of the lipid bimolecular membrane of transfersome. Due to its ultradeformability, it also allows drugs to penetrate the skin, even through the stratum corneum. We hope that this new encapsulation technique will improve the stability and enhance the permeability of RSV. Concluding all the tested parameters, the best production condition was 5% PC/EA (3:1) and 5% ethanol in distilled water, with an ultrasonic bath and stirring at 500 rpm, followed by high pressure homogenization. The optimal particle size was 40.13 ± 0.51 nm and the entrapment efficiency (EE) was 59.93 ± 0.99%. The results of antioxidant activity analysis showed that transfersomes were comparable to the RSV group (unencapsulated). During in vitro transdermal delivery analysis, after 6 h, D1-20(W) increased 27.59% by accumulation. Cell viability assay showed that the cytotoxicity of D3-80(W) was reduced by 34.45% compared with the same concentration of RSV. Therefore, we successfully prepared RSV transfersomes and also improved the stability, solubility, and safety of RSV.

scholarly journals Cytotoxicity of Chelating Agents Used In Endodontics and Their Influence on MMPs of Cell Membranes

2020 ◽  
Vol 31 (1) ◽  
pp. 32-36
Author(s):  
Kellin Pivatto ◽  
Fabio Luis Miranda Pedro ◽  
Orlando Aguirre Guedes ◽  
Adriana Fernandes da Silva ◽  
Evandro Piva ◽  
...  
Keyword(s):  
Cell Viability ◽  
Cytotoxic Effect ◽  
Chelating Agents ◽  
Ethylenediaminetetraacetic Acid ◽  
Gelatin Zymography ◽  
Inhibitory Effect ◽  
Positive Control ◽  
Cell Viability Assay ◽  
Viability Assay ◽  
Diphenyltetrazolium Bromide

Abstract This study evaluated the cytotoxic effect and the ability to inhibit matrix metalloproteinases (MMP-2 and MMP-9) of 0.2% chitosan (CH) and 1% acetic acid (AA) compared with 17% ethylenediaminetetraacetic acid (EDTA). Cell viability assay was performed according to ISO 10993-5 with mouse fibroblasts (L929). The culture was exposed to 0.2% CH, 1% AA, and 17% EDTA. The chelating agents were evaluated immediately after contact with the cells and after 6 h, 12 h, and 24 h of incubation. Cell viability was analyzed using the 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Inhibition of the gelatinolytic activity of MMP-2 and MMP-9 was evaluated by gelatin zymography. Different concentrations of CH were evaluated: 50 mM, 5 mM, 0.5 mM, and 0.05 mM. EDTA (0.5 mM) was used as a positive control. The results demonstrated that CH and AA had an initial cytotoxic effect, which decreased after 6 h, 12 h, and 24 h, being statistically similar to EDTA (P > 0.05). Additionally, CH at concentrations of 50 mM, 5 mM, and 0.5 mM had an inhibitory effect on MMP-2 and MMP-9, similar to that of the control with EDTA. The chelating agents had no cytotoxic effects after 24 h. MMP-2 and MMP-9 were inhibited by the experimental solutions.

Utilization of Tofu Dregs Flour in Making Snack Bars for People with Diabetes Mellitus

2020 ◽  
Vol 7 (1) ◽  
pp. 27
Author(s):  
Ni Putu Diah Cahyani Subamia ◽  
Komang Ayu Nocianitri ◽  
I Dewa Gede Mayun Permana
Keyword(s):  
Diabetes Mellitus ◽  
Blood Sugar ◽  
Wheat Flour ◽  
Sugar Content ◽  
Type Ii Diabetes Mellitus ◽  
Positive Control ◽  
Water Soluble ◽  
Control Group ◽  
Unhealthy Lifestyle ◽  
Control Group Design

Type II diabetes mellitus due to an unhealthy lifestyle, one of which is the lack of fiber in daily food consumption. One food that has a high fiber content is tofu dregs. The purpose of this study was to determine substitution of wheat flour with tofu dregs flour to produce a snack bar with the best characteristics, and determine the effect of consumption of snack bar from tofu dregs on blood sugar content in rats. The research was conducted two steps. Step I: Formulation of snack bar using a completely randomized design with tofu dregs flour concentration of 0 %, 10 %, 20 %, 30 %, 40 %, and 50 %. The variables of this study were the content of water, ash, protein, fat, carbohydrates, sensory tests, and effectiveness tests. Step II: the best characteristic snack bar in the step I was used experimental rats. This step used true experimental design with pre-post test control group design. The variables of study were blood glucose levels before treatment and after treatment. The treatment group consisted of normal, negative, positive control, and snack bar. The results of the first step of the research showed that substitution of wheat flour with 40 % tofu dregs produced the best characteristic snack bar with 17.19 % water content, 1.33 % ash content, 11.03 % protein, 20.53 % fat, 49.92 % carbohydrate, light brown color, unpleasant aroma, distinctive soy taste, crumb texture, 0.63 % water soluble food fiber, 1.57 % water insoluble fiber, and total food fiber 2.36 %. The results of the second step of the study showed that the provision of substitution of wheat flour with tofu dregs flour 40 % could reduce blood sugar levels in diabetic mellitus rats until normal, start 290 mg/dl to 108.5 mg/dl. Tofu dregs flour can be used for snack bar formulations for people with diabetes mellitus.

Study of Rabies Protein Antibodies Marked with Water-Soluble Quantum Dots

2013 ◽  
Vol 40 (6) ◽  
pp. 857-861
Author(s):  
Bin ZHAO ◽  
Su-Qing ZHAO ◽  
Li-Hua ZHOU ◽  
Kun ZHANG ◽  
Jun ZHANG
Keyword(s):  
Quantum Dots ◽  
Water Soluble
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