Application Of Gold Nanoparticles Research Articles

A review on gold nanoparticles as an innovative therapeutic cue in bone tissue engineering: Prospects and future clinical applications

Bone damage is a complex orthopedic problem primarily caused by trauma, cancer, or bacterial infection of bone tissue. Clinical care management for bone damage remains a significant clinical challenge and there is a growing need for more advanced bone therapy options. Nanotechnology has been widely explored in the field of orthopedic therapy for the treatment of a severe bone disease. Among nanomaterials, gold nanoparticles (GNPs) along with other biomaterials are emerging as a new paradigm for treatment with excellent potential for bone tissue engineering and regenerative medicine applications. In recent years, a great deal of research has focused on demonstrating the potential for GNPs to provide for enhancement of osteogenesis, reduction of osteoclastogenesis/osteomyelitis, and treatment of bone cancer. This review details the latest understandings in regards to GNPs based therapeutic systems, mechanisms, and the applications of GNPs against various bone disorders. The present review aims to summarize i) the mechanisms of GNPs in bone tissue remodeling, ii) preparation methods of GNPs, and iii) functionalization of GNPs and its decoration on biomaterials as a delivery vehicle in a specific bone tissue engineering for future clinical application.

Designing Gold Nanoparticles for Precise Glioma Treatment: Challenges and Alternatives.

Glioblastoma multiforme (GBM) is a glioma and the most aggressive type of brain tumor with a dismal average survival time, despite the standard of care. One promising alternative therapy is boron neutron capture therapy (BNCT), which is a noninvasive therapy for treating locally invasive malignant tumors, such as glioma. BNCT involves boron-10 isotope capturing neutrons to form boron-11, which then releases radiation directly into tumor cells with minimal damage to healthy tissues. This therapy lacks clinically approved targeted blood-brain-barrier-permeating delivery vehicles for the central nervous system (CNS) entry of therapeutic boron-10. Gold nanoparticles (GNPs) are selective and effective drug-delivery vehicles because of their desirable properties, facile synthesis, and biocompatibility. This review discusses biomedical/therapeutic applications of GNPs as a drug delivery vehicle, with an emphasis on their potential for carrying therapeutic drugs, imaging agents, and GBM-targeting antibodies/peptides for treating glioma. The constraints of GNP therapeutic efficacy and biosafety are discussed.

Correction: A non-sacrificial method for the quantification of poly(ethylene glycol) grafting density on gold nanoparticles for applications in nanomedicine

Correction for ‘A non-sacrificial method for the quantification of poly(ethylene glycol) grafting density on gold nanoparticles for applications in nanomedicine’ by Jun Lu et al., Chem. Sci., 2019, 10, 2067–2074, https://doi.org/10.1039/C8SC02847H.

Conferring the Midas Touch on Integrative Taxonomy: A Nanogold-Oligonucleotide Conjugate-Based Quick Species Identification Tool

Nanogold or functionalized gold nanoparticles (GNPs) have myriad applications in medical sciences. GNPs are widely used in the area of nanodiagnostics and nanotherapeutics. Applications of GNPs in taxonomic studies have not been studied vis-à-vis its extensive medical applications. GNPs have great potential in the area of integrative taxonomy. We have realized that GNPs can be used to visually detect animal species based on molecular signatures. In this regard, we have synthesized gold nanoparticles (<20 nm) and have developed a method based on interactions between thiolated DNA oligonucleotides and small-sized GNPs, interactions between DNA oligonucleotides and target DNA molecules, and self-aggregating properties of small-sized GNPs under high salt concentrations leading to a visible change in colour. Exploiting these intermolecular and interparticle interactions under aqueous conditions, in the present work, we have demonstrated the application of our procedure by using a DNA oligonucleotide probe designed against a portion of the mitochondrial genome of the codling moth Cydia pomonella. This method is accurate, quick, and easy to use once devised and can be used as an additional tool along with DNA barcoding. This tool can be used for distinguishing cryptic species, identification of morphovariants of known species, diet analysis, and identification of pest species in quarantine facilities without any need of performing repetitive DNA sequencing. We suggest that designing and selecting a highly specific DNA probe is crucial in increasing the specificity of the procedure. Present work may be considered as an effort to introduce nanotechnology as a new discipline to the extensive field of integrative taxonomy with which disciplines like palaeontology, embryology, anatomy, ethology, ecology, biochemistry, and molecular biology are already associated for a long time.

Review on Gold Nanoparticles-Based Biosensors in Clinical and Non-Clinical Applications

Gold nanoparticles (GNP) acquire unique properties that have made significant contributions to clinical and non-clinical fields, specifically in the application of GNP’s for designing biosensor devices in which exhibit novel functional properties. Many properties of GNP’s are reviewed in this literature including optical properties, biocompatibility, conductivity, catalytic properties, high surface-to-volume ratio, and high density of the GNPs, that make them excellent in the application of constructing GNP-based biosensors. This literature review covers a specific comparison between the optical, electrochemical, and piezoelectric biosensors, as these are the three most common GNP-based biosensors. Optical biosensors are optimal due to their ability to cater to surface modification, which then leads to the ability for selective bonding. Furthermore, with the use of GNP and the sensor's non-invasive and non-toxic method of use, high-resolution images and signals can be formed. The sensitivity and specificity of electrochemical biosensors with the conductivity of GNPs, the electrodes of this stable biosensor can detect tumour markers in the human body. Piezoelectric biosensors are mass sensitive sensors and with the use of GNP, it amplifies the changes in mass. Through this, these sensors progress to be immunosensors which determine microorganisms and macromolecular compounds. As well, this review will conclude with an outline of present and future research recommendations for real-world application of the three GNP-based biosensors discussed.

Aggregation-induced emission of lead halide perovskites modulated by dispersed/aggregated gold nanoparticles for application in the detection of dopamine

A new kind of lead halide perovskites (LHPs) with aggregation induced emission (AIE) feature is developed. These LHPs are nonemissive when they disperse in good solvent (DMF), but show high brightness when they aggregate in water. The morphology of LHPs changes from nanometer-sized irregular shape to micrometer-sized needle-like, and then to stick-like with increasing water fraction. However, their AIE is quenched by only a few pM of dispersed gold nanoparticles (AuNPs). Dopamine (DA) induces aggregation of AuNPs, resulting in AIE recovery of LHPs. A good linear range of DA is obtained from 0.5 to 50 μM with the limit of detection (LOD) 0.12 μM. In the catalysis of tyrosinase (TYR), DA is oxidized to dopaquinone, resulting in the fluorescence quenching of LHPs again. Therefore, this system is further used for monitoring TYR activity and evaluating inhibitor of TYR. Finally, this method is successfully applied to detecting DA in urine samples.

Gold Nanoparticles from Plant Materials: Green Extraction, Biological Synthesis and Its Beneficials Properties for Cosmeceutical Applications

Green technologies have become trends among researchers and it is developing as the current demand is increased towards products that are processed through green technologies. In this regard, green extraction and green synthesis of gold nanoparticles (GNPs) from plants are presented and discussed. Rapid development in green extraction makes the researchers are competing in providing the best extraction techniques which will use safe extracting solvent, low energy consumption, and did not release hazardous materials as residues of the processes. The same thing goes for the green synthesis of GNPs, plant extracts are used as reducing agent and it does not release any hazardous residues as compared to chemical synthesized GNPs. The application of the GNPs in this paper is reviewed on their properties that are beneficial for cosmeceutical applications. Even though the application of GNPs in the cosmeceutical application in research papers is relatively unexplored, but it has a high potential to be studied since there is existing research that recognizes the properties played by GNPs. The properties that are mostly studied by researchers are an antioxidant, anti-inflammatory, and antibacterial activity that is found to be advantageous in the production of cosmeceutical products.

Recent Advances of Plasmonic Gold Nanoparticles in Optical Sensing and Therapy.

Gold nanoparticles with special surface plasmon resonance have been widely used in sensing and therapy because of their easy preparation, unique optical properties, excellent biocompatibility, etc. The applications of gold nanoparticles in chemo/biosensing, imaging, and therapy reported in 2016-2019, are summarized in this review. Regarding the gold nanoparticle-based sensing or imaging, sensing mechanisms and strategies are provided to illustrate the concepts for designing sensitive and selective detection platforms. Gold nanoparticlemediated therapy is introduced by surface plasmon resonance-based therapy and delivery-based therapy. Beyond the sole therapeutic system, platforms through synergistic therapy are also discussed. In the end, discussion of the challenges and future trends of gold nanoparticle-based sensing and therapy systems is described.

A Monte Carlo study on the radio-sensitization effect of gold nanoparticles in brachytherapy of prostate by 103Pd seeds

Abstract 103Pd seed is being used for prostate brachytherapy. Additionally, the dose enhancement effect of gold nanoparticles (GNP) has been reported in previous studies. The aim of this study was to characterize the dosimetric effect of gold nanoparticles in brachytherapy with a 103Pd source. Two brachytherapy seeds including 103 Pd source was simulated using MCNPX Monte Carlo code. The seeds’ models were validated by comparing the MC with reported results. Then, GNPs (10 nm in diameter) with a concentration of 7mg Au/g were simulated uniformly inside the prostate of a humanoid computational phantom. Additionally, the dose enhancement factor (DEF) of nanoparticles was calculated for both modeled brachytherapy seeds. A good agreement was found between the MC calculated and the reported dosimetric parameters. For both seeds, an average DEF of 23% was obtained in tumor volume for prostate brachytherapy. The application of GNPs in conjunction with 103Pd seed in brachytherapy can enhance the delivered dose to the tumor and consequently leads to better treatment outcome.

Functionalized gold nanoparticles for sample preparation: A review.

Sample preparation is a crucial step for the reliable and accurate analysis of both small molecule and biopolymers which often involves processes such as isolation, pre-concentration, removal of interferences (purification), and pre-processing (e.g., enzymatic digestion) of targets from a complex matrix. Gold nanoparticle (GNP)-assisted sample preparation and pre-concentration has been extensively applied in many analytical procedures in recent years due to the favorable and unique properties of GNPs such as size-controlled synthesis, large surface-to-volume ratio, surface inertness, straightforward surface modification, easy separation requiring minimal manipulation of samples. This review article primarily focuses on applications of GNPs in sample preparation, in particular for bioaffinity capture and biocatalysis. In addition, their most common synthesis, surface modification and characterization methods are briefly summarized. Proper surface modification for GNPs designed in accordance to their target application directly influence their functionalities, e.g., extraction efficiencies, and catalytic efficiencies. Characterization of GNPs after synthesis and modification is worthwhile for monitoring and controlling the fabrication process to ensure proper quality and functionality. Parameters such as morphology, colloidal stability, and physical/chemical properties can be assessed by methods such as surface plasmon resonance, dynamic light scattering, ζ-potential determinations, transmission electron microscopy, Taylor dispersion analysis, and resonant mass measurement, among others. The accurate determination of the surface coverage appears to be also mandatory for the quality control of functionality of the nanoparticles. Some promising applications of (functionalized) GNPs for bioanalysis and sample preparation are described herein.

Use of a lipid nanoparticle system as a Trojan horse in delivery of gold nanoparticles to human breast cancer cells for improved outcomes in radiation therapy

BackgroundRadiotherapy is commonly used for treating cancer. Novel sensitizers, such as gold nanoparticles (GNPs), are being used to enhance the local radiation dose. It is not known how the uptake and radiation dose enhancement of GNPs vary in synchronized vs unsynchronized (control) tumor cell populations. Successful application of GNPs in radiation therapy requires NPs to be accumulated within individual tumor cells at clinically feasible NP concentrations. Use of small GNPs as a radiation dose enhancer in the past required very high NP concentration, since the driving force for the uptake of smaller GNPs is low. We used a novel lipid-based NP of 50 nm diameter system as a Trojan horse to deliver smaller GNPs of size 5 nm (LNP–GNP) at 0.2 nM concentration. We investigated the changes in GNP uptake and survival fraction with the LNP delivery at different cell stages using human breast cancer as our tumor model and choosing the triple-negative MDA-MB-231 cell line.ResultsUsing the LNP–GNP system resulted in a 39- and 73-fold enhancement in uptake of 5 nm GNPs in unsynchronized and synchronized tumor cell populations, respectively. The NP uptake per cell increased from 800 to 1200 and from 30,841 to 88,477 for individual 5 nm GNPs and 5 nm GNPs incorporated in LNPs, respectively. After a radiation dose of 2 Gy with 6 MeV photons, synchronized tumor cell populations incorporated with LNP–GNPs produced a 27% enhancement in tumor cell death compared to the control (unsynchronized; no GNPs; 2 Gy). The findings of our experimental results were supported by modeling predictions based on Monte Carlo calculations.ConclusionsThis study clearly shows that the cell cycle, GNPs, and radiation therapy can be combined to improve outcome of cancer therapy. Using the experimental data, we estimated the predicted improvement for a clinical treatment plan where 30 fractions of 2 Gy radiation dose were given over a period of time. Enhanced uptake and radiation sensitivity of a synchronous tumor cell population would produce a significant improvement in cell killing. For example, synchronizing cells and the addition of LNP–GNPs into tumor cells produced a 1000-fold enhancement in cell killing. Because the agents used for cell synchronization are in clinical practice, this approach may be a simple and cost-effective way to further enhance local radiation dose. Finally, this study provides a novel lipid-based NP platform to further improve GNP-mediated radiation therapy through synchronization of breast cancer cell population.

One-pot sonocatalyzed synthesis of sol–gel graphite electrodes containing gold nanoparticles for application in amperometric sensing

We propose here a one-pot synthetic approach to prepare sol–gel graphite electrodes containing gold nanoparticles (AuNPs). At variance with the traditional synthesis, in which AuNPs are prepared in advance with respect to the silica matrix, they were here obtained directly inside the sol–gel, during its formation. Two reduction methods, namely chemical and thermal reduction, were used to achieve AuNPs starting from a suitable gold precursor, either consisting of NaAuCl4 or HAuCl4. Different experimental parameters were tested in order to direct the synthesis of the material to the characteristics sought, namely Si/Au molar ratio, graphite (g): silane precursor (mL) ratio, chemical nature of the gold precursor and of the reductant, duration and temperature of thermal treatment. Sol–gel was prepared by means of sonocatalysis, in order to reduce the amount of solvent and time necessary for the hydrolysis step. Composition of the material, as well as shape, size and distribution of AuNPs inside the silica matrix was evaluated by spectroscopic and microscopic techniques. Furthermore, electrochemical tests allowed us to ascertain the good conductivity of the composite material and the electrocatalytic activity of AuNPs with respect to glucose and ascorbic acid oxidation. These tests demonstrated that the electrodes obtained by thermal reduction show the best performance in terms of sensitivity for the detection of these analytes, suggesting the possible application of this composite in the field of amperometric sensing.

A non-sacrificial method for the quantification of poly(ethylene glycol) grafting density on gold nanoparticles for applications in nanomedicine.

The grafting density of poly(ethylene glycol) (PEG) on nanoparticle (NP) surfaces is the most important parameter determining the interaction of nanoparticles with serum proteins, the subsequent sequestration of the nanoparticle from the bloodstream by the mononuclear phagocyte system, and the eventual delivery efficiency to tumor tissues. However, the majority of in vivo studies do not characterize or report the grafting density of PEG on nanoparticles due to a lack of feasible characterization methods, making it difficult to evaluate the published studies and reconcile apparent conflicting results. Herein, we develop a facile and non-sacrificial 1H NMR analytical approach for the quantitative characterization of grafting density of thiol-terminated PEG (HS-PEG) on gold NPs (GNPs). A multi-Lorentzian-splitting algorithm is used to distinguish the NMR signal of free PEG from those of the grafted ones, therefore allowing in situ monitoring of the grafting process to study the effects of GNP sizes, PEG molecular weights and NP capping ligands on grafting rates and grafting densities. The main advantage of this method is that it is not limited by the types of terminal functional groups on PEG, surface chemistry of the nanoparticles or their composition. It also provides a set of critical and standard guides for characterization of the PEG grafting density on nanoparticles for in vivo biological and biomedical studies.

A REVIEW ON GOLD NANOPRTICLES SYNTHESIS AND CHARACTERIZATION

Gold nano particles (GNP) have exceptional biocompatibility and possess unique structural, electronic, magnetic, optical, catalytic and molecular recognition properties. Hence GNPs are very attractive for many biological applications. Being noble metal, the GNPs are resistant to oxide formation. Their electronic, magnetic and optical properties are size dependent. The optical properties of gold nano particles depend on nano particles size, shape, aggregation state, and local environment and are tuneable throughout the visible and near-infrared region. The current paper gives a brief review of different methods of synthesis of GNP with uniform size and shape and characterization of GNP by UV spectroscopy, dynamic light scattering, scanning electron microscopy and Fourier transform Infra Red spectroscopy along with applications of GNPs. Peer Review History: Received 1 July 2017; Revised 5 August; Accepted 2 September, Available online 15 September 2017 Academic Editor: Dr. Ali Abdullah Al-yahawi, Al-Razi university, Department of Pharmacy, Yemen, alyahawipharm@yahoo.com Received file: Reviewer's Comments: Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Dr. Sally A. El-Zahaby, Pharos University in Alexandria, Egypt, sally.elzahaby@yahoo.com Dr. Maha Khalifa Ahmed Khalifa, Al-Azhar Universit - Cairo, Egypt, mahakhalifa.ahmed@hotmail.com Similar Articles: SCREENING STUDY FOR FORMULATION VARIABLES IN PREPARATION AND CHARACTERIZATION OF CANDESARTAN CILEXETIL LOADED NANOSTRUCTURED LIPID CARRIERS

DNA-assisted decoration of single-walled carbon nanotubes with gold nanoparticles for applications in surface-enhanced Raman scattering imaging of cells

Single-walled carbon nanotubes (SWNTs) are 1D nanostructures with distinct physical and chemical properties that have shown great promise for applications in many fields, including biomedicine. Since for biomedical application the water solubility is crucial and SWNTs have low solubility, various methods (including polymer and biopolymer wrapping, chemical modifications) have been developed to solubilize and disperse them in water. Due to their unique optical properties such as photoluminescence in the NIR and strong resonant Raman signatures, they can be used as nanoprobes in biomedical imaging and phototherapies. Furthermore, decoration of SWNTs with noble metal nanoparticles will induce an excellent surface-enhanced Raman scattering (SERS) effect of the nanoparticles-SWNTs composites, with applications in cell imaging. Herein, we present a new and facile strategy for the DNA-assisted decoration of SWNTs with gold nanoparticles (AuNPs) and their application in SERS imaging. By ultrasonication at room temperature of SWNTs with AuNPs functionalized with synthetic DNA, SWNT-AuNPs nanocomposites with enhanced Raman signal were obtained. Among the important advantages of the proposed method are the presence of the free DNA overhangs around the SWNT-AuNPs suitable for post-synthetic modification of nanocomposite through hybridization of complementary DNA strands containing molecules of interest attached by well-developed bio-conjugation chemistry.

Gold nanoparticles, radiations and the immune system: Current insights into the physical mechanisms and the biological interactions of this new alliance towards cancer therapy.

Considering both cancer's serious impact on public health and the side effects of cancer treatments, strategies towards targeted cancer therapy have lately gained considerable interest. Employment of gold nanoparticles (GNPs), in combination with ionizing and non-ionizing radiations, has been shown to improve the effect of radiation treatment significantly. GNPs, as high-Z particles, possess the ability to absorb ionizing radiation and enhance the deposited dose within the targeted tumors. Furthermore, they can convert non-ionizing radiation into heat, due to plasmon resonance, leading to hyperthermic damage to cancer cells. These observations, also supported by experimental evidence both in vitro and in vivo systems, reveal the capacity of GNPs to act as radiosensitizers for different types of radiation. In addition, they can be chemically modified to selectively target tumors, which renders them suitable for future cancer treatment therapies. Herein, a current review of the latest data on the physical properties of GNPs and their effects on GNP circulation time, biodistribution and clearance, as well as their interactions with plasma proteins and the immune system, is presented. Emphasis is also given with an in depth discussion on the underlying physical and biological mechanisms of radiosensitization. Furthermore, simulation data are provided on the use of GNPs in photothermal therapy upon non-ionizing laser irradiation treatment. Finally, the results obtained from the application of GNPs at clinical trials and pre-clinical experiments in vivo are reported.

Oligonucleotide-Conjugated Gold Nanoparticles for Application on Lateral Flow Biosensors: Evaluation and Optimization of Low pH and Salt-Aging Conjugation Methods

ABSTRACTPaper-based lateral flow biosensors (LFBs) have been shown to be optimal for rapid analysis, since they exhibit user-friendly format, low analysis times, and no need for specialized instrumentation or highly trained personnel. Low detection limits are desirable for a variety of diagnostic applications, indicating the need for optimal detection labels primarily based on gold nanoparticles. Oligonucleotide-functionalized gold nanoparticles have attained great interest as LFB detection components and study of efficient conjugation methods is ongoing. However, a comparative investigation of oligonucleotide–gold nanoparticle conjugates for application as LFBs has not been performed. Therefore, the goal of the present study was the evaluation of two oligonucleotide–gold nanoparticles conjugation methods, and optimization of the most promising reaction. An LFB for nucleic acids detection was utilized for the evaluation study. Two conjugation protocols were tested: the pH 3 citrate method and the salt-aging method. The prepared conjugates were evaluated in terms of particle color and signal intensity, with a reference oligonucleotide that was used as a model system. Subsequently, the salt-aging protocol, which resulted in better oligonucleotide–gold nanoparticle conjugates, was optimized regarding several reaction parameters. Finally, the conjugate detection sensitivity and reproducibility were assessed.

Novel Preparation of Gold Nanoparticles with Application for the Amperometric Determination of Arsenic

ABSTRACTA novel synthesis of gold nanoparticles is reported by chemical reduction of chloroauric acid with polyethylenimine and trisodium citrate. The use of polyethylenimine and trisodium citrate provided a convenient route to produce gold nanoparticles with diameters between 3.7 and 11.8 nm. The resulting nanoparticles were characterized by ultraviolet-visible spectroscopy, transmission electron microscopy, and zeta potential measurements. Transmission electron microscopy provided imaging of the shape and size of the nanoparticles. In order to characterize the solubility of the gold nanoparticles for application as an electrochemical sensor, the zeta potential, hydrodynamic diameter, electrophoretic mobility, and surface area-to-volume ratio were determined. The gold nanoparticles were incorporated on a glassy carbon electrode to produce an amperometric sensor for the determination of arsenic.

Cytotoxicity of gold nanoparticles in human neural precursor cells and rat cerebral cortex

Nanoparticles are promising tools for the advancement of drug delivery, medical imaging, and as diagnostic sensor. Medical nanodevices should develop miniaturization, because it would be injected into a human body. Gold nanoparticles (GNPs) with different sizes and shapes have therapeutic potential as a result of their small size, robust nature, excellent biocompatibility and optical properties. However, the application of GNPs as medical nanodevices it is necessary to know the biodegradation, biocompatibility, and development of surface coating which avoid the accumulation of nanoparticles. In this study, we carry out an in vitro toxicity and in vivo gene expression study using two kinds of GNPs. We found that GNPs toxicity is dependent on the dose or size administrated after the injected GNPs into the brain, and small particle size GNPs appeared more nestin expression compared to large particle size at short term implantation. These findings of toxicity of GNPs may play an important role in development of in vivo tools for the safety of GNPs.

Tube Glass Waveguides Modified With Gold Nanoparticles for Application as a Simple Chemical and Biological Sensor

A low-cost, simple, and stable optical chemical and biological sensor was prepared using a U-shaped glass tube, whose 200-μm-thick wall coated with a colored layer serves as a sensitive waveguide. Light from a LED is launched into the glass wall of the tube from an endface and emits from the other endface to be detected with a silicon photodetector. The refractive-index (RI) sensitivity of the sensor is mainly attributed to the clad-RI-induced enhancement of evanescent field that results in the increased absorption of the colored layer. The sensor's sensitivity can be effectively improved by hydrofluoric acid etching of the bent portion of the U-shaped tube before deposition of the colored layer. The gold-nanoparticle (GNP) monolayer was used as the colored layer in this paper, and the GNP self-assembly process that took more than 12 h was in situ monitored with the sensor. The resulting sensor can easily detect a small change of 1 wt% in sucrose concentration, and is also applicable for real-time detection of bimolecular adsorption and immunoreaction.