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DC reactive magnetron sputtering of zinc target in argon-oxygen sputtering atmosphere has been used to grow ZnO thin films/nanorods on Si in a wide substrate temperature range of 300-750 degrees C and under different sputtering conditions, namely, DC power, sputtering pressure and oxygen percentage in the sputtering atmosphere. Powder X-ray diffraction, Raman spectroscopy and a combination of top-down and cross-sectional scanning electron microscopy studies of ZnO films and nanorods grown under different conditions, have shown that substrate temperature critically controls their growth behavior and morphology, eventually resulting in the growth of vertically c-axis oriented, highly aligned and separated ZnO nanorods at substrate temperatures of 700-750 degrees C. The strongly substrate temperature dependent growth of nanorods is explained by considering that the growth above 600 degrees C, takes place in the 'desorption regime', in which, the surface diffusion length decreases exponentially with temperature. The diameter of nanorods increases with increase of DC power or decrease of sputtering pressure, which is attributed to the increase of surface diffusion length at higher deposition flux. The morphology of ZnO nanorods is not significantly affected by oxygen percentage in the sputtering atmosphere, since it does not influence the deposition flux. (C) 2016 Elsevier B.V. All rights reserved.

Pesticidi su kemijske ili biološke tvari koje se koriste s ciljem sprječavanja djelovanja različitih nametnika, korova i prijenosnika bolesti pri uzgoju hrane. Kao onečišćivači predstavljaju vrlo visok rizik za ljudsko zdravlje. Količina pesticida u hrani ograničena je zakonima postavljenim uz savjete Europske agencije za sigurnost hrane; ona odobrava korištenje pesticida pri zaštiti biljaka i životinja ovisno o mogućnoj daljnjoj štetnosti na zdravlje i okoliš. Dopuštena količina ovisi i o samom proizvodu (npr. voće, mliječni proizvodi...), a vrijednosti variraju oko 1 mg/kg proizvoda. Budući da se pesticidi u prehrambenim proizvodima pojavljuju u vrlo niskim koncentracijama, za njihovo otkrivanje potrebno je koristiti vrlo osjetljive metode. Količina pesticida u ovom radu analizirana je Ramanovim spektrometrom koristeći metodu površinski pojačanog Ramanovog raspršenja (engl. Surface-Enhanced Raman Scattering, SERS), koja pojačava odziv molekula apsorbiranih na nanostrukturama plemenitih metala. Za potrebe promatranja pesticida pripremljene su dvije vrste nanostruktura srebra: nanoprizme i nanosfere. SERS metoda korištena je u svrhu detekcije malih koncentracija pesticida, ali i za proučavanje utjecaja različitih nanostruktura (prizme, sfere) na samu detekciju. Pesticides are chemical or biological substances used to prevent activity of different types of pests, weeds and diseases in food cultivation. Yet, they present a severe risk to human health as pollutants. The allowed amount of pesticides in food is limited by laws with the help of European agency for food safety which approves the usage of pesticides for plants and animal protection on EU territory, considering the possible side-effects on human health and environment. The allowed amount depends on the product in which the residue could be found (e.g. fruit, dairy products, etc.) but it usually varies around 1 mg/kg of product. Considering that concentrations of pesticides in food products are rather low, a highly sensitive method must be applied for pesticide detection. In this paper pesticides were determined by Surface-Enhanced Raman Scattering; SERS, which increases response of molecules adsorbed on noble metals nanostructures. Two different types of nanoparticles were applied in this research: nanospheres and nanoprisms. SERS method was used to detect small concentrations of pesticides, but also to study the effect that different nanostructures (prisms or spheres) might have on the detection.

Screen-printed carbon nanofiber electrodes (SPCNFEs) represent an alternative with great acceptance due to their results, as well as their low impact on the environment. In order to improve their performance, in the present work they were modified with silver nanoparticles (Ag-NPs) and electrochemically characterized by using anodic stripping voltammetry. From the Ag-NP synthesis, silver seeds (Ag-NS) and silver nanoprisms (Ag-NPr) were obtained. The Ag-NP formation was confirmed by micrographs, where Ag-NPs with diameters of 12.20 &plusmn, 0.04 nm for Ag-NS and 20.40 &plusmn, 0.09 nm for Ag-NPr were observed. The electrodes were modified by using three different deposition methods&mdash, drop-casting, spin-coating, and in situ approaches&mdash, that offer different nanoparticle distribution and electrode modification times. It was observed that the last methodology showed a low amount of Ag-NS deposited on the electrode surface and deep alteration of this surface. Those facts suggest that the in situ synthesis methodology was not appropriate for the determination of heavy metals, and it was discarded. The incorporation of the nanoparticles by spin-coating and drop-casting strategies showed different spatial distribution on the electrode surface, as proved by scanning electron microscopy. The electrodes modified by these strategies were evaluated for the cadmium(II) and lead(II) detection using differential pulse anodic stripping voltammetry, obtaining detection limit values of 2.1 and 2.8 &micro, g&middot, L&minus, 1, respectively. The overall results showed that the incorporation route does not directly change the electrocatalytic effect of the nanoparticles, but the shape of these nanoparticles (spherical for seeds and triangular for prisms) has preferential electrocatalytic enhancement over Cd(II) or Pb(II).

Triangular silver nanocrystals, well-known as nanoprisms (Ag-NPrs), were successfully developed via a robust and straightforward direct chemical reduction synthetic approach, producing desirable tiny and well-controlled Ag-NPrs. This procedure was accomplished by fabricating a mixture of di-sodium succinate hexa-hydrate (DSSH) and tri-sodium citrate di-hydrate (TSCD) as capping agents at optimal synthetic conditions and under an open-air condition, which proved to be an enormous challenge. Additionally, the Ag-NPrs were fully characterized by UV-vis spectra, X-ray diffraction (XRD), scanning electron microscope (SEM), and dynamic light scattering (DLS). Likewise, the formation stages from spherical silver nanoparticles (Ag-NPs) to triangular Ag-NPrs were also captured simultaneously via transmission electron microscope (TEM) and high-resolution transmission electron microscope (HR-TEM) images. More interestingly, an active thin silica-shell was efficiently applied on the Ag-NPrs outer-layer to increase their functionality. Furthermore, to confirm their biocompatibility, we also carried out cell viability assays for the Ag-NPs, Ag-NPrs, and Ag-NPrs@SiO2 with different concentrations at 62.5, 125, and 250 &micro, g/mL after 12, 24, and 48 h of exposure time, respectively, on a regular African green monkey kidney cell line. The cell viability test results exemplified that the three silver nanostructures were toxic-free and suitable for further potential biological applications in the near future.

Controlling the number of dye molecules on metallic nanoparticles, which in turn affects the magnitude of Rabi splitting energy, is crucial for obtaining hybrid metal core–organic shell nanoparticles with tunable optical properties in the visible spectrum since the magnitude of the Rabi splitting energy directly determines the strength of the coupling between plasmonic nanoparticles and dye molecules. In this work, we present a new method for the synthesis of plexcitonic nanoparticles, and thus we are able to control the number of dye molecules self-assembled on Ag nanoprisms (Ag NPs) by adjusting the concentration of dye molecules used in the synthesis. Indeed, individual dye molecules self-assemble into J-aggregates on Ag NPs. Thus, in the finite-element simulations and experimental data of the hybrid metal organic nanoparticles, we observed a transition from weak coupling to the ultrastrong coupling regime. Besides, ultrafast energy transfer between plasmonic nanoparticles and excitonic aggregated dye molecules has been extensively studied as a function of Rabi splitting energy. We observe that the lifetime of the polariton states increases with the coupling strength and the upper polaritons are short-lived, whereas the lower polaritons are long-lived. Hybrid metal–organic nanoparticles presented in this study (i) have tunable Rabi splitting energies, (ii) are easy to prepare in large quantities in aqueous medium, (iii) can be uniformly assembled on solid substrates, (iv) have resonance frequencies in the visible spectrum, and (v) have small mode volume, thus making them an excellent model system for studying light–matter interaction at nanoscale dimensions from the weak to ultrastrong coupling regime.

У роботі описано спосіб синтезу плазмонних наноструктур золота, здебільшого нанопризм, які мають чисту поверхню. Вони вирощені на модифікованій полівінілпіролідоном (PVP) поверхні дисульфіду молібдену (MoS2). Синтез наноструктур здійснювався у два етапи. На першому етапі було отримано модифіковану поверхню MoS2/PVP, а потім на ній синтезували нанопризми золота у ростовому розчині, що не містив PVP. Для підтвердження чистоти поверхні нанопризм застосовували сканувальну електронну мікроскопію, атомно-силову мікроскопію, а також мікрораманівську спектроскопію. Here we report on the synthesis of plasmonic gold nanostructures, preferably nanoprisms, having clean surface. They were grown on the molybdenum disulfide (MoS2) modified with polyvinylpyrrolidone (PVP). The synthesis of such nanostructures was carried out in two stages. At the first stage, a modified MoS2/PVP surface was obtained, and then gold nanoprisms were synthesized on this surface in growth solution without PVP. To confirm the cleanliness of nanoprisms, scanning electron microscopy and atomic force microscopy, as well as micro-Raman spectroscopy were applied.

Wet chemical synthesis gives wide possibilities for fabrication of noble metal nanoparticles (NP), which characteristics depend on many factors. The article is devoted to study of formation of Au nanostructures on MoS2 substrate from growth solution, containing ethanol, ethylene glycol, glycerin, polyvinylpyrrolidone (PVP) and HAuCl4. The study shows that obtained particles in this system are nearly spherical NP, wires, flat triangle and hexagonal nanoprisms (NPRs). NPs and dendritic structures growth without PVP and only presence of stabilizer leads to formation and further evolution of NPRs on MoS2 substrate. For the first time it was also observed a growth of incomplete triangle and hexagonal NPRs, consisting of NP with size 50-100 nm. These incomplete nanoprisms transform to full shapes later on. Our experiments reveal that changing of component concentrations, ratio [PVP]/[HAuCl4] and time of synthesis have a dominant influence on the shape of obtained NP. The possible mechanisms of NP growth on MoS2 are discussed. Синтез у водному середовищі надає широкі можливості для виготовлення наночастинок (НЧ) благородних металів, характеристики яких залежать від багатьох факторів. Стаття присвячена дослідженню росту наноструктур Au на підкладці MoS2 у ростовому середовищі, що містить етанол, етиленгліколь, гліцерин, полівінілпіролідон (ПВП) та HAuCl4. Наші дослідження показують, що морфологія отриманих НЧ є близькою до сферичної, дротоподібною або у вигляді плоских трикутних/гексагональних нанопризм (НПР). Ріст НЧ та дендритоподібних структур може відбуватись і без ПВП, та лише наявність стабілізатора призводить до утворення та еволюції НПР на інтерфейсі MoS2. Виявлено поетапний ріст незавершених трикутних і гексагональних НПР, що складалися з окремих НЧ розміром 50-100 нм. Такі структури перетворюються згодом у повноцінні НПР. Наші експерименти показують, що варіація концентрації компонентів, співвідношення [ПВП] / [HAuCl4] та часу синтезу безпосередньо впливають на розмір та форму отримах НЧ. Обговорюються можливі механізми росту отримах структур Au на MoS2. Синтез в водной среде предоставляет широкие возможности для изготовления наночастиц (НЧ) благородных металлов, характеристики которых зависят от многих факторов. Статья посвящена исследованию роста наноструктур Au на подложке MoS2 в ростовой среде, содержащей этанол, этиленгликоль, глицерин, поливинилпирролидон (ПВП) и HAuCl4. Наши исследования показывают, что морфология полученных НЧ близка к сферической, проводоподобной или в виде плоских треугольных/ гексагональных нанопризм (НПР). Рост НЧ и дендритоподобных структур может происходить и без ПВП, и только наличие стабилизатора приводит к образованию и эволюции НПР на интерфейсе MoS2. Наблюдается поэтапный рост незавершенных треугольных и гексагональных НПР, состоящих из отдельных НЧ размером 50-100 нм. Такие структуры превращаются со временем в полноценные НПР. Наши эксперименты показывают, что вариация концентрации компонентов, соотношения [ПВП] / [HAuCl4] и времени синтеза непосредственно влияют на размер и форму синтезированных НЧ. Обсуждаются возможные механизмы роста полученных структур Au на MoS2.

Aluminum nanostructures have recently been at the focus of numerous studies due to their properties including oxidation stability and surface plasmon resonances covering the ultraviolet and visible spectral windows. In this article, we reveal a new facet of this metal relevant for both plasmonics purpose and photo-thermal conversion. The field distribution of high order plasmonic resonances existing in two-dimensional Al structures is studied by nonlinear photoluminescence (nPL) microscopy in a spectral region where electronic interband transitions occur. The polarization sensitivity of the field intensity maps shows that the electric field concentration can be addressed and controlled on-demand. We use a numerical tool based on the Green dyadic method to analyze our results and to simulate the absorbed energy that is locally converted into heat. The polarization-dependent temperature increase of the Al structures is experimentally quantitatively measured, and is in an excellent agreement with theoretical predictions. Our work highlights Al as a promising candidate for designing thermal nanosources integrated in coplanar geometries for thermally assisted nanomanipulation or biophysical applications., 8 pages 6 figures main article; 7 pages 9 figures supporting informations

Anisotropic plasmonic noble metallic nanoparticles (APMNs) have received enormous attention due to their distinct geometric features and fascinating physicochemical properties. Owing in large part to their tailored localized surface plasmon resonance (LSPR) and the intensive electromagnetic field at the sharp corners and edges, APMNs are exceptionally well suited for biomedical applications such as biosensing, bioimaging, diagnostics and therapeutics. Although a rich variety of surfactant-assisted colloidal routes have been developed to prepare well-defined APMNs, biomedical applications necessitate tedious and rigorous purification processes for the complete removal of toxic surfactants. In this dissertation, we aim to develop generic bioenabled green synthetic methodologies towards APMNs. By applying a series of thermodynamic, kinetic and seed quality control, a series of APMNs with varied morphologies such as branched nanostars and triangular nanoprisms have been successfully prepared. We first presented the preparation of gold nanostars (Au NSTs) through a two-step approach utilizing a common Good's buffer, HEPES, as a weak reducing agent. Single crystalline Au NSTs with tunable branches up to 30 nm in length were produced and the halide ions rather than the ionic strength played a significant roles on the length of the branches of Au NSTs. Then consensus sequence tetratricopetide repeat (CTPR) proteins with increasing number of repeats were used as model proteins to probe the effects of concentration as well as the protein shape on the morphology and resulting physicochemical properties of plasmonic gold nanoparticles. Since the underlying growth mechanism for the biomimetic synthesis of APMNs remains elusive and controversial, the other objective is to elucidate the molecular interactions between inorganic species and biopolymers during the course of NP evolution. Fluorescent quenching and 2D NMR experiments have confirmed the moderate binding affinity of CTPR to the Au(0) and Au(III). We observed that the initial complexation step between gold ions and CTPR3 is ionic strength dependent. Furthermore, we also found that NPs preferentially interact with the negatively charged face of CTPR3 as observed in 2D NMR. Knowledge of binding behavior between biospecies and metal ions/NPs will facilitate rational deign of proteins for biomimetic synthesis of metallic NPs. A modified seed-mediated synthetic strategy was also developed for the growth of silver nanoprisms with low shape polydispersity, narrow size distribution and tailored plasmonic absorbance. During the seed nucleation step, CTPR proteins are utilized as potent stabilizers to facilitate the formation of planar-twinned Ag seeds. Ag nanoprisms were produced in high yield in a growth solution containing ascorbic acid and CTPR-stabilized Ag seeds. From the time-course UV-Vis and transmission electron microscopy (TEM) studies, we postulate that the growth mechanism is the combination of facet selective lateral growth and thermodynamically driven Ostwald ripening. By incorporation of seeded growth and biomimetic synthesis, gold nanotriangles (Au NTs) with tunable edge length were synthesized via a green chemical route in the presence of the designed CTPR protein, halide anions (Br⁻) and CTPR-stabilized Ag seeds. The well-defined morphologies, tailored plasmonic absorbance from visible-light to the near infrared (NIR) region, colloidal stability and biocompatibility are attributed to the synergistic action of CTPR, halide ions, and CTPR-stabilized Ag seeds. We also ascertained that a vast array of biosustainable materials including negatively charged lignin and cellulose derivatives can serve as both a potent stabilizers and an efficient nanocrystal modifiers to regulate the growth of well-defined Ag nanoprisms using a one-pot or seeded growth strategy. The influential effects of reactants and additives including the concentration of sodium lignosulfonate, H2O2 and NaBH4 were studied in great detail. It implies that appropriate physicochemical properties rather than the specific binding sequence of biomaterials are critical for the shaped-controlled growth of Ag NTs and new synthetic paradigms could be proposed based on these findings. Last but not the least, we have demonstrated the resulting APMNs, particularly, Au NSTs and Ag NTs exhibit remarkable colloidal stability, enhanced SERS performance, making them promising materials for biosensing and photothermal therapy. Since the Ag nanoprisms are susceptible to morphological deformation in the presence of strong oxidant, they also hold great potential for the colorimetric sensing of oxidative metal cation species such as Fe3+, Cr3+, etc. Ph. D.

MicroRNAs (miRs) are small noncoding RNAs that regulate mRNA stability and/or translation. Because of their release into the circulation and their remarkable stability, miR levels in plasma and other biological fluids can serve as diagnostic and prognostic disease biomarkers. However, quantifying miRs in the circulation is challenging due to issues with sensitivity and specificity. This Letter describes for the first time the design and characterization of a regenerative, solid-state localized surface plasmon resonance (LSPR) sensor based on highly sensitive nanostructures (gold nanoprisms) that obviates the need for labels or amplification of the miRs. Our direct hybridization approach has enabled the detection of subfemtomolar concentration of miR-X (X = 21 and 10b) in human plasma in pancreatic cancer patients. Our LSPR-based measurements showed that the miR levels measured directly in patient plasma were at least 2-fold higher than following RNA extraction and quantification by reverse transcriptase-polymerase chain reaction. Through LSPR-based measurements we have shown nearly 4-fold higher concentrations of miR-10b than miR-21 in plasma of pancreatic cancer patients. We propose that our highly sensitive and selective detection approach for assaying miRs in plasma can be applied to many cancer types and disease states and should allow a rational approach for testing the utility of miRs as markers for early disease diagnosis and prognosis, which could allow for the design of effective individualized therapeutic approaches.

Optical printing has been proved a versatile and simple method to fabricate arbitrary arrays of colloidal nanoparticles (NPs) on substrates. Here, we show that is also a powerful tool for studying chemical reactions at the single NP level. We demonstrate that 60 nm gold NPs immobilized by optical printing can be used as seeds to obtain larger NPs by plasmon-assisted reduction of aqueous HAuCl4. The final size of each NP is simply controlled by the irradiation time. Moreover, we show conditions for which the growth occurs preferentially in the direction of light polarization, enabling the in situ anisotropic reshaping of the NPs in predetermined orientations. Fil: Violi, Ianina Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina Fil: Gargiulo, Julian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina Fil: Von Bilderling, Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina Fil: Cortés, Emiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina Fil: Stefani, Fernando Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina

The combination of iron oxide and gold in a single nanoparticle results in both magnetic and plasmonic properties that can stimulate novel applications in bio-sensing, medical imaging, or therapeutics. Microwave assisted heating allows the fabrication of multi-component, multi-functional nanostructures by promoting selective heating at desired sites. Recently, we reported a microwave-assisted polyol route yielding gold nanotriangles decorated with iron oxide nanoparticles. Here, we present an in-depth microstructural and compositional characterization of the system using scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS). A method to remove the iron oxide nanoparticles from the gold nanocrystals and some insights on crystal nucleation and growth mechanisms are also provided., This research was partially funded by the Spanish Ministry of Economy and Competitiveness in co-funding with European Social Funds through the MAT2012-35324 project, the Severo Ochoa Programme for Centers of Excellence in R&D (SEV-2015- 0496) and the Ramón y Cajal program (AL, RyC-2010-06082) and the Generalitat de Catalunya (2014SGR213). Authors also acknowledge support of the Chinese Scholarship Council (SMY, 201206150053) and the following projects: COST Action MP1202, and the U.S. Department of Energy grant DE-FG02- 09ER46554 (JAH, STP). Work at Oak Ridge National Laboratory was supported by the Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.

Досліджено процес утворення і росту нанокристалів золота у неводному середовищі. Встановлено, що формування нанокристалів відбувається за температури 80 ± 1ºС із атомів золота, що утворилися в результаті хімічного відновлення прекурсора (золотохлористоводневої кислоти) у суміші етиленгліколю і етилового спирту в присутності полівінілпіролідону (ПВП), який відіграє роль стабілізатора. Методами ТЕМ, СЕМ і оптичної мікроскопії показано, що утворені кристали мають форму плоских нанопризм (НПр) з гексагональною чи трикутною основою. Товщина НПр знаходиться у діапазоні нанорозмірів. Монокристалічність НПр підтверджено методами електронної дифракції і рентгеноструктурного аналізу. Методом рентгенофазового аналізу показано, що нанокристали золота не мають домішок інших атомів. Експериментально знайдено параметри синтезу (співввідношення HAuCl4 і ПВП, етанолу і етиленгліколю, час і температура), які дозволяють одержувати НПр з лінійними розмірами від десятків нанометрів до десятків мікрон. Обговорюються можливі механізми росту кристалів та вплив на їх морфологію ПВП-стабілізатора. Методом мікрораманівської спектроскопії показано, що взаємодія молекул стабілізатора з поверхнею кристалів відбувається через С=О і C-N групи піролідонового кільця полівінілпіролідону. Исследован процесс образования и роста нанокристаллов золота в неводной среде. Установлено, что формирование нанокристаллов происходит при температуре 80 ± 1 ºС из атомов золота, образующихся в результате химического восстановления прекурсора (золотохлористоводородной кислоты) в смеси этиленгликоля и этилового спирта в присутствии поливинилпирролидона (ПВП), выступающего в роли стабилизатора. Методами ТЭМ, СЭМ и оптической микроскопии показано, что образующие- ся кристаллы имеют форму плоских нанопризм (НПр) с гексагональным или треугольным основанием. Толщина НПр находится в диапазоне наноразмеров. Монокристалличность НПр подтверждена методами электронной дифракции и рентгеноструктурного анализа. Методом рентгенофазового анализа показано, что нанокристаллы золота не имеют примесей инородных атомов. Экспериментально найдены параметры синтеза (соотношения HAuCl4 и ПВП, этанола и этиленгликоля, время и темпе- ратура), позволяющие получать НПр с линейными размерами от десятков нанометров до десятков микрон. Обсуждаются возможные механизмы роста кристаллов и влияние на их морфологию ПВП- стабилизатора. Методом микрорамановской спектроскопии показано, что взаимодействие молекул стабилизатора с поверхностью кристаллов происходит за счет С=О и C-N групп пирролидонового кольца поливинилпирролидона. The process of gold nanocrystals formation and growth in non-aqueous medium had been studied. The formation of the nanocrystals takes place at the temperature of 80 ± 1 ºС from gold atoms produced as a result of chemical reduction of the precursor (chloroauric acid) in a mixture of ethylene glycol and ethanol in the presence of polyvinylpyrrolidone (PVP) acting as a stabilizer. It had been demonstrated by TEM, SEM and optical microscopy that the crystals formed are in the form of flat nanoprisms (NP) with hexagonal or triangular base. These NP have thickness in the nanoscale range. Monocrystallinity of the NP had been confirmed by electron diffraction and X-ray analysis. The X-ray analysis testifies that gold nanocrystals have no foreign atom impurities. The experimentally determined parameters of synthesis (HAuCl4 and PVP, ethanol and ethylene glycol ratios, time and temperature) allow to obtain the NP with the linear dimensions of tens of nanometers to tens of microns. Possible mechanisms of crystal growth and the impact of PVP stabilizer on their morphology are discussed. It had been demonstrated by micro-Raman spectroscopy that the interaction of the stabilizer molecules with the crystals surface is due to the C=O and CN groups of the pyrrolidone ring of PVP.