Low Concentrations Of Gold Nanoparticles Research Articles

Contrast-to-noise ratio comparison between X-ray fluorescence emission tomography and computed tomography.

We provide a comparison of X-ray fluorescence emission tomography (XFET) and computed tomography (CT) for detecting low concentrations of gold nanoparticles (GNPs) in soft tissue and characterize the conditions under which XFET outperforms energy-integrating CT (EICT) and photon-counting CT (PCCT). We compared dose-matched Monte Carlo XFET simulations and analytical fan-beam EICT and PCCT simulations. Each modality was used to image a numerical mouse phantom and contrast-depth phantom containing GNPs ranging from 0.05% to 4% by weight in soft tissue. Contrast-to-noise ratios (CNRs) of gold regions were compared among the three modalities, and XFET's detection limit was quantified based on the Rose criterion. A partial field-of-view (FOV) image was acquired for the phantom region containing 0.05% GNPs. For the mouse phantom, XFET produced superior CNR values ( , 21.6, and 3.4) compared with CT images obtained with both energy-integrating ( , 4.6, and 1.5) and photon-counting ( , 7.7, and 2.0) detection systems. More generally, XFET outperformed CT for superficial imaging depths ( ) for gold concentrations at and above 0.5%. XFET's surface detection limit was quantified as 0.44% for an average phantom dose of 16mGy compatible with in vivo imaging. XFET's ability to image partial FOVs was demonstrated, and 0.05% gold was easily detected with an estimated dose of to a localized region of interest. We demonstrate a proof of XFET's benefit for imaging low concentrations of gold at superficial depths and the feasibility of XFET for in vivo metal mapping in preclinical imaging tasks.

Low Concentrations of Gold Nanoparticles as Electric Charge Carriers in Piezoelectric Cement-Based Materials.

Piezoelectric cement-based composites could serve to monitor the strain state of structural elements or act as self-powered materials in structural health monitoring (SHM) applications. The incorporation of piezoelectric materials as an active phase within cement matrices has presented a highly attractive avenue until today. However, their application is challenged by the low electrical conductivity of the hydrated cement matrix. Gold nanoparticles (Au NPs) possess substantial potential for elevating the free electrical charge within the matrix, increasing its electrical conductivity between the Au NPs and the cement matrix, thereby enhancing the piezoelectric response of the composite. In this sense, the objective of this study is to investigate the effects of incorporating low concentrations of gold nanoparticles (Au NPs) (442 and 658 ppm) on the electrical and piezoelectric properties of cement-based composites. Additionally, this study considers the effects of such properties when the material is cured under a constant electric field. Electrical impedance spectroscopy was used to evaluate the polarization resistance and piezoresistive properties of the material. Additionally, open-circuit potential measurements were taken alongside the application of mechanical loads to assess the piezoelectric activity of the composites. The findings revealed a notable decrease in the composite's total electrical resistance, reaching a value of 1.5 ± 0.2 kΩ, almost four times lower than the reference specimens. In the realm of piezoelectricity, the piezoelectric voltage parameter g33 exhibited a remarkable advancement, improving by a factor of 57 when compared to reference specimens. This significant enhancement can be attributed to both the concentration of Au NPs and the electrical curing process. In summary, the outcomes of this study underscore the feasibility of creating a highly electrically conductive cement-based matrix, using low concentrations of gold nanoparticles as electric charge carries, and indicate the possible piezoelectric behavior of the studied compposite.

Nanocomposites Based on Antiferroelectric Liquid Crystal (S)-MHPOBC Doping with Au Nanoparticles.

Modification of the physical properties of the (S)-MHPOBC antiferroelectric liquid crystal (AFLC) by doping with low concentrations of gold nanoparticles is presented for the first time. We used several complementary experimental methods to determine the effect of Au nanoparticles on AFLC in the metal–organic composites. It was found that the dopant inhibits the matrix crystallization process and modifies the phase transitions temperatures and switching time, as well as increases the helical pitch and spontaneous polarization, while the tilt angle slightly changes. We also showed that both the LC matrix and Au nanoparticles show strong fluorescence in the green light range, and the contact angle depends on the temperature and dopant concentration.

Light luminescence and trapping in polydimethylsiloxane foils with low concentration of gold nanoparticles

Light trapping and luminescence have been observed in polydimethylsiloxane (PDMS) foils containing about 0.1–0.2 wt% gold nanoparticles (AuNPs). The so-prepared PDMSs have been physically characterized using SEM microscopy, UV–Vis, FTIR and Raman spectroscopies. The used AuNPs have been controlled by means of the surface plasmon resonance absorption spectra. In the AuNPs–PDMS foils, a luminescence peak at about 425 nm has been induced by an exciting light at 280 nm. The light injection with an optical fiber is trapped inside the polymer-containing NPs and illuminates all the polymer volume. The measurements of scattered light show an increment in the light intensity due to the presence of AuNPs and air bubbles inducing diffractions, reflections and Mie scattering. Further investigations have been conducted irradiating the PDMS with AuNPs in vacuum with 2.9 MeV proton beams producing luminescence in the blue region. The mechanisms of light trapping and luminescence and the possible applications of the prepared material are presented and discussed.

Incorporation of Low Concentrations of Gold Nanoparticles: Complex Effects on Radiation Response and Fate of Cancer Cells.

(1) Background: In oncology research, a long-standing discussion exists about pros and cons of metal nanoparticle-enhanced radiotherapy and real mechanisms behind the tumor cell response to irradiation (IR) in presence of gold nanoparticles (GNPs). A better understanding of this response is, however, necessary to develop more efficient and safety nanoparticle (NP) types designed to disturb specific processes in tumor cells. (2) Aims and Methods: We combined 3D confocal microscopy and super-resolution single molecule localization microscopy (SMLM) to analyze, at the multiscale, the early and late effects of 10 nm-GNPs on DNA double strand break (DSB) induction and repair in tumor cells exposed to different doses of photonic low-LET (linear energy transfer) radiation. The results were correlated to different aspects of short and long-term cell viability. SkBr3 breast cancer cells (selected for the highest incidence of this cancer type among all cancers in women, and because most breast tumors are treated with IR) were incubated with low concentrations of GNPs and irradiated with 60Co γ-rays or 6 MV X-rays. In numerous post-irradiation (PI) times, ranging from 0.5 to 24 h PI, the cells were spatially (3D) fixed and labeled with specific antibodies against γH2AX, 53BP1 and H3K9me3. The extent of DSB induction, multi-parametric micro- and nano-morphology of γH2AX and 53BP1 repair foci, DSB repair kinetics, persistence of unrepaired DSBs, nanoscale clustering of γH2AX and nanoscale (hetero)chromatin re-organization were measured by means of the mentioned microscopy techniques in dependence of radiation dose and GNP concentration. (3) Results: The number of γH2AX/53BP1 signals increased after IR and an additional increase was observed in GNP-treated (GNP(+)) cells compared to untreated controls. However, this phenomenon reflected slight expansion of the G2-phase cell subpopulation in irradiated GNP(+) specimens instead of enhanced DNA damage induction by GNPs. This statement is further supported by some micro- and nano-morphological parameters of γH2AX/53BP1 foci, which slightly differed for cells irradiated in absence or presence of GNPs. At the nanoscale, Ripley’s distance frequency analysis of SMLM signal coordinate matrices also revealed relaxation of heterochromatin (H3K9me3) clusters upon IR. These changes were more prominent in presence of GNPs. The slight expansion of radiosensitive G2 cells correlated with mostly insignificant but systematic decrease in post-irradiation survival of GNP(+) cells. Interestingly, low GNP concentrations accelerated DSB repair kinetics; however, the numbers of persistent γH2AX/53BP1 repair foci were slightly increased in GNP(+) cells. (4) Conclusions: Low concentrations of 10-nm GNPs enhanced the G2/M cell cycle arrest and the proportion of radiosensitive G2 cells, but not the extent of DNA damage induction. GNPs also accelerated DSB repair kinetics and slightly increased presence of unrepaired γH2AX/53BP1 foci at 24 h PI. GNP-mediated cell effects correlated with slight radiosensitization of GNP(+) specimens, significant only for the highest radiation dose tested (4 Gy).

Optical concentration of gold nanoparticles as a new concept of analytical sensitivity

Concentration procedures have always been implemented when trace analysis of compounds in real matrices is contemplated. A variety of concentration strategies have been reported aiming at decreasing the limits of detection (LODs). The optical concentration of the substance in solution is one of the novel concepts for the enhancement of the analytical sensitivity. In this study, the optical concentration has been measured by the trapping of gold nanoparticles ( nm) dispersed in water at low-concentrations at the focal volume of the laser beam. The influence of factors such as the time of gold nanoparticle trapping, the size of the nanoparticles, the intensity of the laser beam, their solution concentration have been reported on the accumulation of gold nanoparticles in the solution. The results showed at different laser intensities, the capacity of the optical trap changed. At low concentrations of gold nanoparticles, the signal increased linearly with the concentration until the capacity of the optical trap was filled. Also, the best optical concentration efficiency was observed when the time of trapping increased to a period of 40 s. Under the optimum conditions, the relative concentration increase of gold nanoparticles was calculated across the range of to particles at the focal volume of the laser beam for the range from particle/mL of gold nanoparticles in the solution at a laser intensity of mW. This approach may be used to quantitatively determine of gold nanoparticles, supermolecules, and other nanoparticles.

Optimization of the dielectric and optical parameters of 1,2,4-oxadiazole ferroelectric mesophase with the suspension of PVP capped gold nanoparticles

In the present work, the dielectric and optical parameters have been optimized for ferroelectric liquid crystal (FLC), 1,2,4-Oxadiazole compound (C12*C10) when dispersed with PVP capped gold nanoparticles (GNPs). Dielectric (permittivity, loss) and optical-spectroscopic (UV–Visible absorbance, FTIR, and photoluminescence spectra) properties have been investigated to probe into the effect of the electromagnetic field on pure and GNPs dispersed FLC matrix. Polarizing optical textures of GNPs dispersed FLC matrix display enhanced alignment of FLC molecules for the superior performance in optical devices. The dielectric permittivity of FLC matrix has been observed to be decreasing with increase in concentration of GNPs as function of temperature due to the charge transfer properties between FLC and GNPs. The relaxation frequency is shifted to the low-frequency region in case of low concentration of GNPs in ferroelectric mesophase. UV–Visible absorbance of the synthesized composites is used to calculate optical density and skin depth of the materials. The phenomenon of surface plasmon resonance observed in GNPs has been employed to probe in the utility of the FLC driven optical waveguide designing. The experimental results may be utilized in the fabrication of opto-communication network device and optical sensors.

Biochemical Changes in Human Cells Exposed to Low Concentrations of Gold Nanoparticles Detected by Raman Microspectroscopy.

The toxicological implications of nanoparticles deserve accurate scientific investigation for the protection of human health. Although toxic effects involve specific organs, the events that cause them have their origin from biochemical modifications of some cellular constituents. Therefore, a first analysis to evaluate the effects due to the action of nanoparticles is achieved by investigation of in vitro cells, which allows the identification of the cellular modifications caused by nanoparticles (NPs) even at much lower doses than the lethal ones. This work evaluated the Raman microspectroscopy capability to monitor biochemical changes occurring in human cells as a consequence of exposure to a suspension of gold nanoparticles with a non-cytotoxic concentration. Human keratinocyte cells were used as a model cell line, because they are mainly involved in environmental exposure. A trypan blue assay revealed that the investigated concentration, 650 ng/mL, is non-cytotoxic (about 5% of cells died after 48 h exposure). Specific Raman spectral markers to represent the cell response to nanoparticle exposure were found (at 1450 and 2865 cm−1) in the cytoplasm spectra, with the aid of ratiometric and principal component analysis.

Naked Gold Nanoparticles and hot Electrons in Water

The ionizing radiation in aqueous solutions of gold nanoparticles, stabilized by electrostatic non-covalent intermolecular forces and steric interactions, with antimicrobial compounds, are investigated with picosecond pulse radiolysis techniques. Upon pulse radiolysis of an aqueous solution containing very low concentrations of gold nanoparticles with naked surfaces available in water (not obstructed by chemical bonds), a change to Cerenkov spectrum over a large range of wavelengths are observed and pre-solvated electrons are captured by gold nanoparticles exclusively (not by ionic liquid surfactants used to stabilize the nanoparticles). The solvated electrons are also found to decay rapidly compared with the decay kinetics in water. These very fast reactions with electrons in water could provide an enhanced oxidizing zone around gold nanoparticles and this could be the reason for radio sensitizing behavior of gold nanoparticles in radiation therapy.

Segmental Mobility Studies of Poly(N-isopropyl acrylamide) Interactions with Gold Nanoparticles and Its Use as a Thermally Driven Trapping System.

Thermal desolvation of poly(N-isopropylacrylamide) (PNIPAM) in the presence of a low concentration of gold nanoparticles incorporates the nanoparticles resulting in suspended aggregates. By covalently incorporating <1% acenaphthylene into the polymerization feed this copolymer is enabled to be used as a model to study the segmental mobility of the PNIPAM backbone in response to gold nanoparticles both below and above the desolvation temperature, showing that there is a physical conformational rearrangement of the soluble polymer at ultralow nanoparticle loadings, indicating low affinity interactions with the nanoparticles. Thermal desolvation is capable of extracting >99.9% of the nanoparticles from their solutions and hence demonstrates that poly(N-isopropylacrylamide) can act as an excellent scrubbing system to remove metallic nanomaterial pollutants from solution.

Output power enhancement of Rh6G dye laser by colloidal gold nanoparticles

Improvement of the efficiency of a Rh6G dye laser by adding proper concentrations of gold colloidal nanoparticles into the dye solution has experimentally been investigated. Gold colloidal nanoparticles due to their strong plasmonic peak in the visible region are expected to have a considerable interaction with Rh6G dye molecules with broad emission spectrum in the visible range. It is shown that with addition of enough low concentrations (less than 0.4 µM/l) of gold nanoparticles to the dye solution, both the output power and the efficiency of the dye laser increase. The best improvement of the laser efficiency reaches 15%. Two amplifying mechanisms exist for efficiency improvement by the nanoparticles, which are resonant energy transfer from the plasmonic nanoparticles to the dye molecules in addition to the high near field around the nanoparticles. The results indicate that in the low concentrations of gold nanoparticles, the amplifying mechanisms dominate the dissipating mechanism of scattering of the pumped light by the nanoparticles. This leads to the efficiency improvement by addition of the nanoparticles.

SU‐G‐IeP3‐07: High‐Resolution, High‐Sensitivity Imaging and Quantification of Intratumoral Distributions of Gold Nanoparticles Using a Benchtop L‐Shell XRF Imaging System

Purpose:To demonstrate the ability to perform high‐resolution imaging and quantification of sparse distributions of gold nanoparticles (GNPs) within ex vivo tumor samples using a highly‐sensitive benchtop L‐shell x‐ray fluorescence (XRF) imaging system.Methods:An optimized L‐shell XRF imaging system was assembled using a tungsten‐target x‐ray source (operated at 62 kVp and 45 mA). The x‐rays were filtered (copper: 0.08 mm &amp; aluminum: 0.04 mm) and collimated (lead: 5 cm thickness, 3 cm aperture diameter) into a cone‐beam in order to irradiate small samples or objects. A collimated (stainless steel: 4 cm thickness, 2 mm aperture diameter) silicon drift detector, capable of 2D translation, was placed at 90° with respect to the beam to acquire XRF/scatter spectra from regions of interest. Spectral processing involved extracting XRF signal from background, followed by attenuation correction using a Compton scatter‐based normalization algorithm. Calibration phantoms with water/GNPs (0 and 0.00001–10 mg/cm3) were used to determine the detection limit of the system at a 10‐second acquisition time. The system was then used to map the distribution of GNPs within a 12×11×2 mm3 slice excised from the center of a GNP‐loaded ex vivo murine tumor sample; a total of 110 voxels (2.65×10−3 cm3) were imaged with 1.3‐mm spatial resolution.Results:The detection limit of the current cone‐beam benchtop L‐shell XRF system was 0.003 mg/cm3 (3 ppm). Intratumoral GNP concentrations ranging from 0.003 mg/cm3 (3 ppm) to a maximum of 0.055 mg/cm3 (55 ppm) and average of 0.0093 mg/cm3 (9.3 ppm) were imaged successfully within the ex vivo tumor slice.Conclusion:The developed cone‐beam benchtop L‐shell XRF imaging system can immediately be used for imaging of ex vivo tumor samples containing low concentrations of GNPs. With minor finetuning/optimization, the system can be directly adapted for performing routine preclinical in vivo imaging tasks. Supported by NIH/NCI grant R01CA155446This investigation was supported by NIH/NCI grant R01CA155446.

X-ray Imaging Beyond Transmission CT: Detecting Low Concentrations of Gold Nanoparticles

X-ray Imaging Beyond Transmission CT: Detecting Low Concentrations of Gold Nanoparticles

TH‐A‐213CD‐07: Feasibility of Direct L‐Shell Fluorescence Imaging of Gold Nanoparticles Using a Benchtop X‐Ray Source

Purpose: To test the feasibility of benchtop direct fluorescence imaging of small objects loaded with low concentration of gold nanoparticles (GNPs) using gold L‐shell fluorescence x‐rays for pre‐clinical in‐vivo imaging. Methods: 1‐cm diameter cylindrical plastic tubes containing saline solutions and GNPs at 2%, 0%, and 0.5% (by weight), were placed in a vertically stacked geometry and irradiated using a pencil‐beam of 40 kVp x‐rays. A Si‐PIN detector, placed at 90° with respect to the beam axis such that it had a view along the longitudinal axes of the tubes, captured the spectrum of scattered and gold L‐shell fluorescence photons from the cylinders. Keeping the detector and source positions fixed, the distance from the source to the point of interrogation was kept constant by translation of the stack of tubes vertically and horizontally in steps of 2.5 mm until all tubes were imaged. The resulting gold fluorescence signals were extracted and used to generate a rudimentary 2‐D direct fluorescence image of the tubes. Results: Gold La and Lß fluorescence signals (9.7 and 11.4 keV) were detected with very high signal‐to‐background ratios (up to a factor of 3). The direct 2‐D fluorescence image reconstructed from the experimental geometry accurately showed the positions of each tube and relative GNP concentrations. The relative signal strength from each tube had a linear correlation with GNP concentration. The current results were extrapolated to a GNP detection limit on the order of parts‐per‐million. Conclusions: 2‐D fluorescence imaging of GNP location and concentration within small objects can be accomplished by detection of gold L‐shell fluorescence x‐rays. The current benchtop experimental setup can be easily adapted for in‐/ex‐vivo imaging. After further optimization, this setup can be used to image intra‐tumoral distribution of GNPs in vivo during pre‐clinical animal studies. Supported by NIH/NCI grant 1R01CA155446. Supported by NIH/NCI grant 1R01CA155446

Microscopic dynamics in nanocomposite photosensitive films studied by X-ray photon correlation spectroscopy

X-ray photon correlation spectroscopy measurements are reported of microscale dynamics in Langmuir–Schaeffer deposited multilayers of a photosensitive azopolymer with a low concentration of gold nanoparticles embedded. Correlation functions were measured as a function of exchanged momentum and illumination conditions (dark and UV light) and fitted with the Kohlrausch-Williams-Watts (KWW) exponential form. The microscopic dynamic of the nanoparticles was quantified, evidencing a non-Brownian superdiffusive behavior with relaxation times τ ≈ q −1, a result analogous to what previously had been observed in the pure azopolymer. Such behavior has been related to intermittent rearrangements or random dipolar interactions within an elastic medium. Photoperturbation with UV light makes the dynamics faster, in accordance with the reduction of the viscosity of the polymer found by shear rheology, but the KWW form of the correlation functions persists. At constant temperature, the dynamics of the nanoparticles embedded in the polymeric matrix is sensibly faster than the slow microscopic dynamic of the polymer. At the same time, the Vogel–Fulcher–Tammann law for the relaxation times indicates a less pronounced temperature dependence than for the pure polymer, resulting in a slightly lower activation temperature T A.

Influence on fluorescence properties of hyperbranched poly(amidoamine)s by nano golds

The influence of gold nanoparticles (GNPs) and gold nanodots (GNDs) on fluorescence properties of hyperbranched poly(amidoamine)s (HPAMAMs) which were synthesized by Michael addition of 1-(2-aminoethyl) piperazine (AEPZ) and methyl acrylate (MA) was investigated in this study. It was found that GNPs with definite surface plasma absorption can quench the fluorescence of HPAMAMs. With the increasing of the concentration of GNPs, the fluorescence intensity of HPAMAMs decreased correspondingly, and varied linearly at low concentration of GNPs. This phenomenon was owing to the fluorescence resonance energy transfer (FRET) between the HPAMAMs and GNPs. In contrast, the complex with smaller GNDs encapsulated in the interior of the HPAMAMs presented greatly enhanced emission. Those results show that the size of nano golds may be used to adjust the fluorescence properties of HPAMAMs and may extend potential applications of HPAMAMs and GNPs.

Concentration effect of gold nanoparticles on proliferation of keratinocytes

34 nm gold nanoparticles with good stability were synthesized and characterized and their effect (as a function of concentration) on the proliferation of keratinocytes was evaluated by means of MTT and nucleolar organizer region (AgNOR) count (silver staining). The cell morphology was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results demonstrate that a low concentration of gold nanoparticles enhances the proliferation of keratinocytes. Specifically, a concentration of 5.0 ppm gold nanoparticle has the best effect on the promotion of cell growth. In the experiment group, the AgNOR-positive areas and AgNOR area/nuclear area ratios of keratinocytes co-cultured with 5.0 ppm gold nanoparticles were greater than those in the control group ( p < 0.01). At a level greater than10.0 ppm, gold nanoparticles were found to have a cytotoxic effect on keratinocytes. It is concluded that a low concentration of gold nanoparticles may be used as a biomedical material in skin tissue engineering.

Investigation the effects of nano golds on the fluorescence properties of the sectorial poly(amidoamine) (PAMAM) dendrimers

The influence of nano golds on fluorescence properties of sectorial Polyamidoamine dendrimers (G4 s-PAMAM) was investigated in this paper. It was found that gold nanoparticles (GNPs) with definite surface plasmon absorption can quench the fluorescence of G4 s-PAMAM dendrimers. With the increasing of the concentration of GNPs, the fluorescence intensity of G4 s-PAMAM decreased correspondingly, and varied linearly at low concentration of GNPs. This phenomenon was owing to the fluorescence resonance energy transfer (FRET) between the dendrimers and GNPs. In contrast, the complex with smaller gold nanodots (GNDs) encapsulated in the interior of the G4 s-PAMAM presented greatly enhanced emission. Those results show that the size of nano golds may be used to adjust the fluorescence properties of sectorial PAMAM dendrimers and may extend potential applications of PAMAM dendrimers and nano golds.

Toxicologic effects of gold nanoparticles in vivo by different administration routes

Gold nanoparticles have potential applications in biomedicine, but one of the important concerns is about their safety. Most toxicology data are derived from in vitro studies and may not reflect in vivo responses. Here, an animal toxicity study of 13.5 nm gold nanoparticles in mice is presented. Animal survival, weight, hematology, morphology, and organ index are characterized at different concentrations (137.5–2200 μg/kg) over 14–28 days. The results show that low concentrations of gold nanoparticles do not cause an obvious decrease in body weight or appreciable toxicity, even after their breakdown in vivo. High concentrations of gold nanoparticles induced decreases in body weight, red blood cells, and hematocrit. It was also found that gold nanoparticles administered orally caused significant decreases in body weight, spleen index, and red blood cells. Of the three administration routes, the oral and intraperitoneal routes showed the highest toxicity, and the tail vein injection showed the lowest toxicity. Combining the results of all of these studies, we suggest that targeted gold nanopartices by tail vein injection may be suitable for enhancement of radiotherapy, photothermal therapy, and related medical diagnostic procedures.

Irradiation stability and cytotoxicity of gold nanoparticles for radiotherapy

Gold nanoparticles are promising as a kind of novel radiosensitizer in radiotherapy. If gold nanoparticles are shown to have good irradiation stability and biocompatibility, they would play an important role in radiotherapy. In this work, we investigated irradiation effects of gold nanoparticles under 2-10 kR gamma irradiation and cytotoxicity of gold nanoparticles with human K562 cells by using Cell Titre-Glo luminescent cell viability assay. The results revealed that gamma irradiation had not induced any obvious instability and size variations in gold nanoparticles. We found that gold nanoparticles showed excellent radiation hardness with an absorbed dose conversation factor of 9.491 rad/R. Meanwhile, the surface plasmon resonance of gold nanoparticles was enhanced obviously after 2-10 kR gamma irradiation. Subsequently, cytotoxicity tests indicated that the extremely high concentration of gold nanoparticles could cause a sharp decrease in K562 cell viability, while the low concentration of gold nanoparticles had no obvious influence on the cell viability. Our results revealed that gold nanoparticles were stable under high-energy ray irradiation and showed concentration-dependent cytotoxicity.