Extracellular Biomineralization and Synthesis of Gold and Platinum Nano- and Microcrystals in Polysaccharide Aqueous Solutions

Estrela-Llopis, V. R.; Borodinova, T. I.; Yurkova, I. N.

doi:10.1201/ebk1420065008-c12

Cited by 5 publications

(4 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During second one these particles become catalysts of chemical reaction and pores are formed under them. Pore shape and density depend on both stages conditions [18]. MACE process generally is more controlled than conventional porous silicon formation.…”

Section: Metal-assisted Chemical Etchingmentioning

confidence: 99%

Hydrogen Peroxide Measurements by MISFET and LET Structures with Rear Porous Silicon Layer and Metallic Nanoparticles

Kutova

Obukhova

Dusheiko

et al. 2018

Mìkrosist. elektron. akust.

View full text Add to dashboard Cite

In the paper hydrogen peroxide MISFET and LET sensor performance is investigated. As hydrogen peroxide is a product of many chemical reactions, especially biological reactions, peroxide sensors are now widely used for detection of another. In this work, a combination of two nanostructures that are now used for hydrogen peroxide detection-porous silicon and metal nanoparticles was used. A MISFET (metal-insulator-semiconductor field effect transistor) was chosen as the basic sensor but unlike conventional FET sensors sensitive area was formed on the rear side of the sensor. In the aim to simplify sensor structure a LET (lighteffect transistor) with sensitive area on the rear side was also tested. LET structure was produced by the same technology as FET, but then subgate system was removed by chemical etching. Porous silicon was formed by metal-assisted chemical etching (MACE) that consists of two stages. During the first stage, metallic nanoparticles are deposited on the surface by chemical or physical deposition. During second one these particles become catalysts of chemical reaction and pores are formed under them. Pore shape and density depend on both stages conditions. Formation of porous silicon on the rear side leads to changes of substrate charge and influence gate-source curve as well as drain-source curve. Drain current for FET with an active area is lower due to the negative charge accumulated in porous silicon thanks to high tie connections concentration. Dependence of LET drain current on LED intensity (current) is almost linear and drain-source curves are similar to FET structure ones. FET samples with porous silicon/Pt and LET samples with porous silicon/Ag both show more stable and well-defined dependence of drain current on hydrogen peroxide concentration then samples without porous layer. All sensors have saturation of drain current from concentrations of hydrogen peroxide about 0.5-1% and dependence on concentration is first order exponential decay, obviously due to saturation of working area by reaction products or heating effect of hydrogen peroxide decomposition. In concentration range up to 0.3%

show abstract

Section: Metal-assisted Chemical Etchingmentioning

confidence: 99%

Hydrogen Peroxide Measurements by MISFET and LET Structures with Rear Porous Silicon Layer and Metallic Nanoparticles

Kutova

Obukhova

Dusheiko

et al. 2018

Mìkrosist. elektron. akust.

View full text Add to dashboard Cite

show abstract

“…These PSs were previously investigated when developing the method of the "green" synthesis of single crystalline gold nanoprisms and cubic nanocrystals of PtCl 2 [40]. As was shown with the use of high performance gel permeation chromatography, they represent high molecular mass compounds with an average molecu lar mass of 500 kDa, while Raman spectroscopy showed the presence of ionized carboxyl and hydroxyl groups in them.…”

Section: Introductionmentioning

confidence: 97%

Heterocoagulation of polysaccharide-coated platinum nanoparticles with ovarian-cancer cells

et al. 2014

View full text Add to dashboard Cite

Platinum nanoparticles coated with adsorption layers of polysaccharides of Chlorella vulgaris (Pt PS ) have been synthesized and their heterocoagulation with human ovarian cancer cells of the A2780 line has been studied. It has been shown that the characteristic time of the aggregation of the cells with Pt PS nano particles is 20-25 min, which corresponds to fast barrierless coagulation. The cytotoxic effect of Pt PS nano particles reaches saturation and more than 50% of the cells die within this time period. Cytomorphological investigations have shown that A2780 cells with doubled resistance to an antitumoral antibiotic, doxorubicin, are more sensitive to the toxic action of Pt PS nanoparticles than nonresistant cells are. An electrokinetic con trol test has been proposed for cancer cell resistance based on the measurement of variations in the ζ poten tial of nanoparticles due to adsorption of water soluble metabolites of the cells on a particle surface.

show abstract

“…Among one-stage methods, one can distinguish biosynthesis, photoreduction, thermal method, polyol synthesis. Products of the vital activity of microorganisms [28,29], extracts of plants [30], fungi [31] are used as reductions of Au ions and stabilizers of NPrs during bio-synthesis. Photoreduction requires presence of photocatalyst, stabilizer and a substance that is an electron donor in a growth medium [32].…”

Section: Introductionmentioning

confidence: 99%

Growth of Gold Nanoprisms on Freshly Cleaved Mica Surface

2018

Nanosist. Nanomater. Nanotehnol.

View full text Add to dashboard Cite

A numerous methods are being used for synthesis of gold nanoparticles (NPs) in liquid media, in micelles, and at different interfaces. The size and geometry of NPs depend on parameters of synthesis. Here, we propose the modified polyol method of synthesis of Au NPs on freshly cleaved mica surfaces. In such conditions, the nanoprisms (NPrs) and nearly spherical NPs are being simultaneously formed on the mica substrate. We have determined the parameters of synthesis, with which preferential formation of NPrs is being realized. The percentage of NPrs depends on the surface conditions, in particular, on wettability of the surface by growth medium. We demonstrate that both the size and the morphology of grown NPs can be controlled by means of components of growth medium and parameters of synthesis. Для синтези наночастинок (НЧ) золота у рідких середовищах, міцелах і на твердих підкладинках застосовуються різні методи. Від параметрів синтези залежать розмір і геометрія НЧ. Ми пропонуємо модифіковану поліольну методу синтези НЧ золота на поверхні свіжосколеної слюди. За таких умов на поверхні підкладинки одночасно утворюються нанопризми (НПр) золота та НЧ із формою, близькою до сферичної. Встановлено параметри синтези, за яких формування НПр є домінувальним. Відсоток НПр залежить від стану поверхні слюди, зокрема, від її змочуваности ростовим середовищем. Показано, що розмір і морфологія вирощених НЧ безпосередньо контролюються складом ростового середовища та параметрами синтези. Для синтеза наночастиц (НЧ) золота в жидких средах, мицеллах и на твёрдых подложках применяются различные методы. От параметров синтеза зависят размер и геометрия НЧ. Мы предлагаем модифицированный полиольный метод синтеза НЧ золота на поверхности свежесколотой

show abstract

Extracellular Biomineralization and Synthesis of Gold and Platinum Nano- and Microcrystals in Polysaccharide Aqueous Solutions

Cited by 5 publications

References 1 publication

Hydrogen Peroxide Measurements by MISFET and LET Structures with Rear Porous Silicon Layer and Metallic Nanoparticles

Hydrogen Peroxide Measurements by MISFET and LET Structures with Rear Porous Silicon Layer and Metallic Nanoparticles

Heterocoagulation of polysaccharide-coated platinum nanoparticles with ovarian-cancer cells

Growth of Gold Nanoprisms on Freshly Cleaved Mica Surface

Contact Info

Product

Resources

About