scholarly journals Formation of gold nanoparticles by glycolipids of Lactobacillus casei

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Fumiya Kikuchi ◽  
Yugo Kato ◽  
Kazuo Furihata ◽  
Toshihiro Kogure ◽  
Yuki Imura ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Lactobacillus Casei ◽  
Unsaturated Fatty Acids ◽  
Nanoparticle Synthesis ◽  
Unsaturated Lipids ◽  
Mass Spectrum Analysis ◽  
Before And After ◽  
Gold Nanoparticle Synthesis ◽  
Bulk Gold

Abstract Gold nanoparticles have particular properties distinct from those of bulk gold crystals, and such nanoparticles are used in various applications in optics, catalysis, and drug delivery. Many reports on microbial synthesis of gold nanoparticles have appeared. However, the molecular details (reduction and dispersion) of such synthesis remain unclear. In the present study, we studied gold nanoparticle synthesis by Lactobacillus casei. A comparison of L. casei components before and after addition of an auric acid solution showed that the level of unsaturated lipids decreased significantly after addition. NMR and mass spectrum analysis showed that the levels of diglycosyldiacylglycerol (DGDG) and triglycosyldiacylglycerol (TGDG) bearing unsaturated fatty acids were much reduced after formation of gold nanoparticles. DGDG purified from L. casei induced the synthesis of gold nanoparticles in vitro. These results suggested that glycolipids, such as DGDG, play important roles in reducing Au(III) to Au(0) and in ensuring that the nanoparticles synthesized remain small in size. Our work will lead to the development of novel, efficient methods by which gold nanoparticles may be produced by, and accumulated within, microorganisms.

scholarly journals Continuous synthesis of gold nanoparticles in micro- and millifluidic systems

2018 ◽  
Vol 6 (3) ◽  
Author(s):  
He Huang ◽  
Hendrik du Toit ◽  
Luca Panariello ◽  
Luca Mazzei ◽  
Asterios Gavriilidis
Keyword(s):  
Gold Nanoparticles ◽  
Nanoparticle Synthesis ◽  
Reactor Operation ◽  
Design Procedures ◽  
Time Control ◽  
Starting Point ◽  
Quantitative Understanding ◽  
Gold Nanomaterials ◽  
Gold Nanoparticle Synthesis ◽  
Flow Devices

Abstract Gold nanomaterials have diverse applications ranging from healthcare and nanomedicine to analytical sciences and catalysis. Microfluidic and millifluidic reactors offer multiple advantages for their synthesis and manufacturing, including controlled or fast mixing, accurate reaction time control and excellent heat transfer. These advantages are demonstrated by reviewing gold nanoparticle synthesis strategies in flow devices. However, there are still challenges to be resolved, such as reactor fouling, particularly if robust manufacturing processes are to be developed to achieve the desired targets in terms of nanoparticle size, size distribution, surface properties, process throughput and robustness. Solutions to these challenges are more effective through a coordinated approach from chemists, engineers and physicists, which has at its core a qualitative and quantitative understanding of the synthesis processes and reactor operation. This is important as nanoparticle synthesis is complex, encompassing multiple phenomena interacting with each other, often taking place at short timescales. The proposed methodology for the development of reactors and processes is generic and contains various interconnected considerations. It aims to be a starting point towards rigorous design procedures for the robust and reproducible continuous flow synthesis of gold nanoparticles. Graphical Abstract:

New gold-198 nanoparticle synthesis to be used in cancer treatment

2021 ◽  
Vol 9 (1A) ◽  
Author(s):  
Carla Daruich de Souza ◽  
Carla Daruich de Souza ◽  
Carlos Alberto Zeituni ◽  
Wilmmer Alexander Arcos Rosero ◽  
Beatriz Ribeiro Nogueira ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Cancer Treatment ◽  
Nuclear Reactor ◽  
Nanoparticle Synthesis ◽  
Average Energy ◽  
In Vivo Studies ◽  
Chloroauric Acid ◽  
Repeated Heating

Gold nanoparticles (NPs) have been intriguing scientists for over 100 years. Recently, they have been studied for new applications such as cancer treatment. Although the synthesis of gold nanoparticles is extensively reported, in the majority of cases the methodology is confused and/or not clear. We describe a new synthesis methodology for radioactive gold‐198 NPs. Gold-198 was activated in IPEN IEA-01 nuclear reactor. After that, chloroauric acid (HAuCl4) was formed by dissolving the radioactive gold with aqua regia and performing repeated heating cycles. 0.1 mM HAuCl4 containing 100 μL of 1 M NaOH was prepared in a flask equipped with a reflux condenser. The solution was brought to boil and stirred with a PTFE‐coated magnetic stir‐bar. Then 5 mL of sodium citrate was rapidly added. The reaction turns from light yellow to clear, black, dark purple until the solution attained a wine‐red color (2–3 min). Dynamic light scattering (DLS) confirmed 8 nm particles. The presence of gold‐198 (197.968 g/mol; half‐life: 2.69517; decay mode: β‐; average energy: 1.3723 MeV) was confirmed by an ORTEC HPGe detector. DLS was performed after complete decay confirming the 8 nm diameter maintenance. We were able to achieve radioactive gold‐198 NPs and are performing further studies such as: coating reactions, in‐vitro and in‐vivo studies.

Curcumin conjugated gold nanoparticle synthesis and its biocompatibility

RSC Advances ◽  
2014 ◽  
Vol 4 (4) ◽  
pp. 1808-1818 ◽  
Author(s):  
K. Sindhu ◽  
A. Rajaram ◽  
K. J. Sreeram ◽  
Rama Rajaram
Keyword(s):  
Gold Nanoparticles ◽  
Green Chemistry ◽  
Gold Nanoparticle ◽  
Nanoparticle Synthesis ◽  
Gold Nanoparticle Synthesis

Gold nanoparticles have gained much attention due to their widespread biological and technological applications, and consequently their simpler synthesis via green chemistry has also become of foremost importance.

scholarly journals Continuous flow synthesis of citrate capped gold nanoparticles using UV induced nucleation

RSC Advances ◽  
2017 ◽  
Vol 7 (16) ◽  
pp. 9632-9638 ◽  
Author(s):  
H. du Toit ◽  
T. J. Macdonald ◽  
H. Huang ◽  
I. P. Parkin ◽  
A. Gavriilidis
Keyword(s):  
Particle Size ◽  
Gold Nanoparticles ◽  
Gold Nanoparticle ◽  
Continuous Flow ◽  
Nanoparticle Synthesis ◽  
Nucleation And Growth ◽  
Reactor System ◽  
Growth Phases ◽  
Flow Synthesis ◽  
Gold Nanoparticle Synthesis

A novel multimodal reactor system for separating the nucleation and growth phases of gold nanoparticle synthesis to control particle size.

The impact of the polar core size and external organic media composition on micelle–micelle interactions: the effect on gold nanoparticle synthesis

2015 ◽  
Vol 39 (11) ◽  
pp. 8887-8895 ◽  
Author(s):  
Jorge A. Gutierrez ◽  
M. Alejandra Luna ◽  
N. Mariano Correa ◽  
Juana J. Silber ◽  
R. Darío Falcone
Keyword(s):  
Gold Nanoparticles ◽  
Gold Nanoparticle ◽  
Reverse Micelles ◽  
Nanoparticle Synthesis ◽  
Organic Media ◽  
Core Size ◽  
Media Composition ◽  
Gold Nanoparticle Synthesis ◽  
The Impact

An easy way to modulate reverse micelles as nanoreactors to produce different kinds of gold nanoparticles.

BIOSYNTHESIS AND CHARACTERIZATION OF GOLD NANOPARTICLES USING THE ALGA Kappaphycus alvarezii

2010 ◽  
Vol 09 (05) ◽  
pp. 511-516 ◽  
Author(s):  
P. RAJASULOCHANA ◽  
R. DHAMOTHARAN ◽  
P. MURUGAKOOTHAN ◽  
S. MURUGESAN ◽  
P. KRISHNAMOORTHY
Keyword(s):  
Electron Microscopy ◽  
Gold Nanoparticles ◽  
Gold Nanoparticle ◽  
Kappaphycus Alvarezii ◽  
Nanoparticle Synthesis ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Gold Nanoparticle Synthesis

As a part of our ongoing investigation into the use of algae for gold nanoparticle synthesis, we screened the marine alga Kappaphycus alvarezii, to investigate its efficiency to reduce gold ions as well as the formation of gold nanoparticles. In the present work, we report the reaction condition of the alga K. alvarezii with aqueous gold ions for gold nanoparticle synthesis within the biomass extracellularly. The formation of gold nanoparticles was characterized by UV–Vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) method. Moreover, we have found that the reaction of gold ions with the K. alvarezii biomass under stationary conditions results in the rapid extracellular formation of gold nanoparticles of spherical morphology. The gold nanoparticles are not toxic to the cells that continued to grow after the biosynthesis of the gold nanoparticles.

scholarly journals Evaluation of the gold nanoparticles prepared by ‎green ‎chemistry in ‎the ‎‏treatment of cutaneous candidiasis

2021 ◽  
Author(s):  
Hassan Ayad Kareem ◽  
Hayder Mahmood Samaka ◽  
Wasna’a Mohamed Abdulridha
Keyword(s):  
Gold Nanoparticles ◽  
Antifungal Activity ◽  
Green Chemistry ◽  
Nanoparticle Synthesis ◽  
Diffusion Method ◽  
Olive Leaves ◽  
Cutaneous Candidiasis ◽  
Microscopy Techniques

Background and Objectives: Mineral nanoparticle synthesis via green chemistry is ‎considered a novel ‏procedure ‎that ‎has been introduced into some ‏‎‎industries and medical fields. This ‎paper aimed to focus on ‏synthesized gold ‎nanoparticles ‎‎‎‎(‎AuNPs‎) prepared via green chemistry and ‎their usage in the ‏treatment of cutaneous ‎candidiasis.‎‎ Materials and Methods: This study was performed on the green synthesis of AuNPs using olive leaf extract as a reducing ‎agent‎. The ‎UV‎ visible spectroscopy, X-ray diffraction, and atomic force microscopy techniques ‎were used to detect ‏the concentration of the prepared AuNPs‎. ‎The agar gel diffusion method was used to test ‏the ‎antifungal activity of the ‎‎prepared AuNPs in vitro. ‏Antifungal efficacy of the AuNPs in vivo ‎was tested by the ‎induction of‎‎ cutaneous ‎candidiasis in mice‎. ‎This research was conducted on four groups of mice‎. Groups 1 and 2 were used to evaluate the effectiveness of the AuNPs suspension ‎and ‏Nystatin ointment in the treatment ‎of clinical infection, respectively. Groups 3 ‎and ‎4 were the infected ‎and the non-infected control groups, respectively.‎ Results: Based on the findings, the AuNP synthesis using olive leaves was ‎a suitable and ‎secure method. Moreover, it was found that the AuNP concentration of 40.77 ng‏\‏ml represented the minimum ‎inhibitory concentration for the ‎inhibition of the Candida albicans. The prepared AuNPs were more effective than Nystatin ‎in the ‏treatment ‎of cutaneous candidiasis.‎‎ Conclusion: Preparation of AuNPs via green chemistry using olive leaves as a reducing ‎agent is a ‏safe ‎and easy procedure that can be performed to produce AuNPs. In this study, the AuNPs ‎displayed antifungal ‏activity ‏both in vitro and in vivo.

Electron microscopic study of the membrane glycoproteins in the rat kidney after cisplatin treatment

1989 ◽  
Vol 47 ◽  
pp. 912-913
Author(s):  
S.K. Aggarwal
Keyword(s):  
Alkaline Phosphatase ◽  
Rat Kidney ◽  
Light And Electron Microscopy ◽  
Kidney Tissue ◽  
Membrane Glycoproteins ◽  
Electron Microscopic ◽  
Before And After ◽  
Interstrand Cross Links ◽  
Cross Links

The proposed primary mechanism of action of the anticancer drug cisplatin (Cis-DDP) is through its interaction with DNA, mostly through DNA intrastrand cross-links or DNA interstrand cross-links. DNA repair mechanisms can circumvent this arrest thus permitting replication and transcription to proceed. Various membrane transport enzymes have also been demonstrated to be effected by cisplatin. Glycoprotein alkaline phosphatase was looked at in the proximal tubule cells before and after cisplatin both in vivo and in vitro for its inactivation or its removal from the membrane using light and electron microscopy.Outbred male Swiss Webster (Crl: (WI) BR) rats weighing 150-250g were given ip injections of cisplatin (7mg/kg). Animals were killed on day 3 and day 5. Thick slices (20-50.um) of kidney tissue from treated and untreated animals were fixed in 1% buffered glutaraldehyde and 1% formaldehyde (0.05 M cacodylate buffer, pH 7.3) for 30 min at 4°C. Alkaline phosphatase activity and carbohydrates were demonstrated according to methods described earlier.

Structural integrity after cold storage of human epidermal model in hypothermosol: A correlative ultrastructural and fluorescent assay

1994 ◽  
Vol 52 ◽  
pp. 270-271
Author(s):  
Henry H. Eichelberger ◽  
John G. Baust ◽  
Robert G. Van Buskirk
Keyword(s):  
Cold Storage ◽  
Structural Integrity ◽  
Culture Media ◽  
Cell Structure ◽  
Natural State ◽  
Sodium Cacodylate ◽  
Ruthenium Tetroxide ◽  
Cacodylate Buffer ◽  
Before And After

For research in cell differentiation and in vitro toxicology it is essential to provide a natural state of cell structure as a benchmark for interpreting results. Hypothermosol (Cryomedical Sciences, Rockville, MD) has proven useful in insuring the viability of synthetic human epidermis during cold-storage and in maintaining the epidermis’ ability to continue to differentiate following warming.Human epidermal equivalent, EpiDerm (MatTek Corporation, Ashland, MA) consisting of fully differentiated stratified human epidermal cells were grown on a microporous membrane. EpiDerm samples were fixed before and after cold-storage (4°C) for 5 days in Hypothermosol or skin culture media (MatTek Corporation) and allowed to recover for 7 days at 37°C. EpiDerm samples were fixed 1 hour in 2.5% glutaraldehyde in sodium cacodylate buffer (pH 7.2). A secondary fixation with 0.2% ruthenium tetroxide (Polysciences, Inc., Warrington, PA) in sodium cacodylate was carried out for 3 hours at 4°C. Other samples were similarly fixed, but with 1% Osmium tetroxide in place of ruthenium tetroxide. Samples were dehydrated through a graded acetone series, infiltrated with Spurrs resin (Polysciences Inc.) and polymerized at 70°C.

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