Polymer anchored gold nanoparticles: Synthesis, characterization and antimicrobial activities

Abstract : Gold nanoparticles (GNPs) have diverse optical and photo-thermal properties. It is used for diagnostic imaging because of their ability to absorb near infrared (NIR) and X-rays, and their surface enhanced Raman scattering properties. Recently they are used for drug delivery and more particularly photothermal treatment. Their ability to absorb NIR energy and convert it to heat by a Surface Plasmon Resonance mechanism has made these materials promising for the treatment of tumors. GNPs having diameter higher than 1.4–1.5 nm is found nontoxic to the environment. In the present work, polymer anchored GNPs are synthesized by reducing AuIII to Au0 in presence of either chitosan or polyvinyl alcohol, which act as in situ reducers cum stabilizers. Microscopic techniques (TEM, SEM and DLS) are used to analyse the size, surface morphology and size distribution respectively. The unique mucoadhesive properties of chitosan particularly make the system promising with respect to antimicrobial (anti-bacteria as well as anti-fungus) activities. An attempt has been made to understand the mechanistic path involved in antimicrobial activities. Antimicrobial potential of chitosan anchored gold nanoparticles (GNPc) are noticed even at very low dose. The results of bio-chemical analysis (MDA, NBT, DNA fragmentation and over-expression of heat shock protein) clearly explain antimicrobial activities. Additionally, gold chitosan systems interact with microbial DNA and inhibit the action of DNA repair enzyme. Interestingly, in vitro (rat peritoneal MФ) or in vivo (Wistar rat) analysis exhibits negligible cytotoxicy. Thus the synthesized material (particularly GNPc) is promising as an effective nano therapeutic agent.

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Radiosensitization of Prostate Cancers In Vitro and In Vivo to Erbium-filtered Orthovoltage X-rays Using Actively Targeted Gold Nanoparticles

Scientific Reports ◽

10.1038/s41598-017-18304-y ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 12

Author(s):

Allison M. Khoo ◽

Sang Hyun Cho ◽

Francisco J. Reynoso ◽

Maureen Aliru ◽

Kathryn Aziz ◽

...

Keyword(s):

Gold Nanoparticles ◽

X Rays ◽

Prostate Cancers

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Diagnostic Validity of Digital Imaging Fiber-Optic Transillumination (DIFOTI) and Near-Infrared Light Transillumination (NILT) for Caries in Dentine

Journal of Clinical Medicine ◽

10.3390/jcm9020420 ◽

2020 ◽

Vol 9 (2) ◽

pp. 420

Author(s):

Ana Marmaneu-Menero ◽

José Enrique Iranzo-Cortés ◽

Teresa Almerich-Torres ◽

José Carmelo Ortolá-Síscar ◽

José María Montiel-Company ◽

...

Keyword(s):

Confidence Interval ◽

Qualitative Analysis ◽

Near Infrared ◽

Meta Analysis ◽

Infrared Light ◽

X Rays ◽

Carious Lesions ◽

Sensitivity Specificity

The objective of the study is to analyse the available evidence for the validity of the transillumination method in the diagnosis of interproximal caries. Bibliographic searches were carried out in three data bases (PubMed, Embase, Scopus) with the key words “Transillumination AND caries”. A total of 11 studies were selected for the qualitative analysis and meta-analysis. In the qualitative analysis, both in vivo and in vitro studies were included. The gold standards were tomography, digital radiography, and clinical visual diagnosis. The meta-analysis determined the sensitivity, specificity, and area below the ROC curve relative to the transillumination method in the diagnosis of caries in dentine. Meta-analysis results obtained for transillumination gave a sensitivity value of 0.69 (confidence interval: 0.54–0.81), a specificity value of 0.89 (confidence interval: 0.61–0.98), while giving an AUC value of 0.79 (confidence interval: 0.67–0.87). Transillumination is a method offering moderate validity in the diagnosis of carious lesions in dentine, there is no strong evidence that may enable us to affirm that transillumination may fully substitute X-rays in the complementary diagnosis of carious lesions

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Multifunctional graphene oxide for bioimaging: emphasis on biological research

European Journal of Nanomedicine ◽

10.1515/ejnm-2016-0036 ◽

2017 ◽

Vol 9 (2) ◽

Cited By ~ 5

Author(s):

Do Won Hwang ◽

Byung Hee Hong ◽

Dong Soo Lee

Keyword(s):

Graphene Oxide ◽

Targeted Delivery ◽

Near Infrared ◽

Biological Research ◽

Natural Interaction ◽

Drug Delivery Carrier ◽

Wide Range ◽

Surface Enhanced Raman

AbstractGraphene oxide (GO) nanomaterials offer a wide range of bioimaging applicability. Almost complete quenching ability of fluorescence by GO and natural interaction of GO with single stranded nucleic acid made GO a useful and intriguing multifunctional nanoplatform both as a biosensor for in vitro microplate diagnostics and as a drug delivery carrier for targeted delivery. GO’s large surface area and strong near infrared absorbance contribute to enhancement of a therapeutic effect with abundant loading of drugs for possible photothermal and photodynamic therapy. Bioimaging capability of GO made it a good theranostic tool, while enabling tracing in vivo pharmacokinetics during concurrent treatment. Fluorescence, either signal on or off, Raman and surface-enhanced Raman scattering (SERs), photoacoustic, and radionuclide imaging modalities can be used for theranostic purposes using GO nanomaterials. In this review, we highlight current applications of GO for bioimaging that are classified into in vitro microplate, in vitro cellular and in vivo bioimaging.

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The Role of Rosmarinic Acid on the Bioproduction of Gold Nanoparticles as Part of a Photothermal Approach for Breast Cancer Treatment

Biomolecules ◽

10.3390/biom12010071 ◽

2022 ◽

Vol 12 (1) ◽

pp. 71

Author(s):

Tânia Ferreira-Gonçalves ◽

Maria Manuela Gaspar ◽

João M. P. Coelho ◽

Vanda Marques ◽

Ana S. Viana ◽

...

Keyword(s):

Breast Cancer ◽

Gold Nanoparticles ◽

Rosmarinic Acid ◽

Near Infrared ◽

Active Role ◽

Synthetic Method ◽

Tumor Cell Death ◽

Maximum Absorbance

Breast cancer is a high-burden malignancy for society, whose impact boosts a continuous search for novel diagnostic and therapeutic tools. Among the recent therapeutic approaches, photothermal therapy (PTT), which causes tumor cell death by hyperthermia after being irradiated with a light source, represents a high-potential strategy. Furthermore, the effectiveness of PTT can be improved by combining near infrared (NIR) irradiation with gold nanoparticles (AuNPs) as photothermal enhancers. Herein, an alternative synthetic method using rosmarinic acid (RA) for synthesizing AuNPs is reported. The RA concentration was varied and its impact on the AuNPs physicochemical and optical features was assessed. Results showed that RA concentration plays an active role on AuNPs features, allowing the optimization of mean size and maximum absorbance peak. Moreover, the synthetic method explored here allowed us to obtain negatively charged AuNPs with sizes favoring the local particle accumulation at tumor site and maximum absorbance peaks within the NIR region. In addition, AuNPs were safe both in vitro and in vivo. In conclusion, the synthesized AuNPs present favorable properties to be applied as part of a PTT system combining AuNPs with a NIR laser for the treatment of breast cancer.

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Hyaluronic acid Hydrogels Hybridized with Au-Triptolide Nanoparticle for Intra-articular targeted multi-therapy of Rheumatoid Arthritis

10.21203/rs.3.rs-750774/v2 ◽

2022 ◽

Author(s):

Chenxi Li ◽

Rui Liu ◽

Yurong Song ◽

Dongjie Zhu ◽

Liuchunyang Yu ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Gold Nanoparticles ◽

Hyaluronic Acid ◽

Near Infrared ◽

Mtor Pathway ◽

Collagen Induced Arthritis ◽

Hybrid Hydrogels ◽

Low Dosage

Abstract Triptolide (TP) is a DMARD highly effective in patients with RA. Hyaluronic acid (HA) hydrogels loaded RGD-attached gold nanoparticles containing TP were synthesized to alleviate the toxicity and increase therapeutic specificity. The hydrogels can be applied for targeted photothermal-chemo therapy, and in vivo imaging of RA. Heat was locally generated at the inflammation site after degradation of HA chains due to near-infrared resonance (NIR) irradiation of gold nanoparticles (AuNPs), and TP was released. Administration of the hybrid hydrogels containing low dosage of TP combined with NIR irradiation alleviated arthritic conditions and improved the inflamed joint in collagen-induced arthritis (CIA) mice. In vitro effect of the hydrogel was mediated through decrease of phosphorylation of mTOR and its substrate, p70S6K1, thus inhibiting mTOR pathway.

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αvβ3-Specific Gold Nanoparticles for Fluorescence Imaging of Tumor Angiogenesis

Nanomaterials ◽

10.3390/nano11010138 ◽

2021 ◽

Vol 11 (1) ◽

pp. 138

Author(s):

Marc Pretze ◽

Valeska von Kiedrowski ◽

Roswitha Runge ◽

Robert Freudenberg ◽

René Hübner ◽

...

Keyword(s):

Gold Nanoparticles ◽

Optical Imaging ◽

Tumor Angiogenesis ◽

Near Infrared ◽

Αvβ3 Integrin ◽

A431 Cells ◽

Rgd Peptides ◽

Therapeutic Concepts

This paper reports on the development of tumor-specific gold nanoparticles (AuNPs) as theranostic tools intended for target accumulation and the detection of tumor angiogenesis via optical imaging (OI) before therapy is performed, being initiated via an external X-ray irradiation source. The AuNPs were decorated with a near-infrared dye, and RGD peptides as the tumor targeting vector for αvβ3-integrin, which is overexpressed in tissue with high tumor angiogenesis. The AuNPs were evaluated in an optical imaging setting in vitro and in vivo exhibiting favorable diagnostic properties with regards to tumor cell accumulation, biodistribution, and clearance. Furthermore, the therapeutic properties of the AuNPs were evaluated in vitro on pUC19 DNA and on A431 cells concerning acute and long-term toxicity, indicating that these AuNPs could be useful as radiosensitizers in therapeutic concepts in the future.

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Comparison of Gold Nanospheres, Nanorods, Nanocages and Nanoflowers for Combined Photothermal-Radiotherapy of Cancer

NANO ◽

10.1142/s1793292021500375 ◽

2021 ◽

pp. 2150037

Author(s):

Lijie Yang ◽

Jinhua Wang ◽

Liying Sun ◽

Yisi Zhang ◽

Peng Huang ◽

...

Keyword(s):

Gold Nanoparticles ◽

Conversion Efficiency ◽

Near Infrared ◽

Enhancement Effect ◽

Gold Nanospheres ◽

Photothermal Conversion ◽

Uptake Efficiency ◽

Gold Nanoflowers

Gold nanoparticles are promising dual agents for combined photothermal-radiotherapy of cancer. Nevertheless, the shape effects of gold nanoparticles on photothermal conversion efficiency and radiosensitization have not been completely revealed. To address this knowledge gap, different shapes of gold nanoparticles including gold nanospheres (GNSs), gold nanorods (GNRs), gold nanocages (GNCs) and gold nanoflowers (GNFs) were synthesized. Despite being subjected to the same modification with poly (ethylene glycol) (PEG), these gold nanoparticles showed different cellular uptake efficiencies: GNFs[Formula: see text][Formula: see text][Formula: see text]GNSs[Formula: see text][Formula: see text][Formula: see text]GNCs[Formula: see text][Formula: see text][Formula: see text]GNRs. Moreover, GNRs, GNCs and GNFs could convert near-infrared (NIR) light to heat and GNFs displayed the highest photothermal conversion efficiency, whereas GNSs showed poor photothermal effects due to the weak NIR absorption. The highest uptake efficiency as well as the best photothermal conversion ability led to GNFs to exhibit the best photothermal therapeutic effect. Furthermore, all the gold nanoparticles could be used as radiosensitizers to improve radiotherapeutic effect. Among these nanoparticles, GNFs showed the best radiation enhancement effect because of their highest uptake efficiency. Furthermore, a higher accumulation of GNFs in tumor tissues was observed than those of other shaped gold nanoparticles. Importantly, our in vitro and in vivo comparative studies revealed that GNFs possessed the strongest anticancer effect in combined photothermal-radiotherapy. Hence, compared to gold nanoparticles with other shapes, the GNFs might be more desirable dual agents for highly efficient combined photothermal-radiotherapy.

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Surface-ligand effect on radiosensitization of ultrasmall luminescent gold nanoparticles

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545816420037 ◽

2016 ◽

Vol 09 (04) ◽

pp. 1642003 ◽

Cited By ~ 6

Author(s):

Xingya Jiang ◽

Bujie Du ◽

Mengxiao Yu ◽

Xun Jia ◽

Jie Zheng

Keyword(s):

Gold Nanoparticles ◽

Near Infrared ◽

Survival Rates ◽

Ligand Effect ◽

Surface Ligand ◽

Surface Chemistries ◽

Mcf 7

Gold nanoparticles (AuNPs) could serve as potential radiotherapy sensitizers because of their exceptional biocompatibility and high-Z material nature; however, since in vitro and in vivo behaviors of AuNPs are determined not only by their particle size but also by their surface chemistries, whether surface ligands can affect their radiosensitization has seldom been investigated in the radiosensitization of AuNPs. By conducting head-to-head comparison on radiosensitization of two kinds of ultrasmall ([Formula: see text][Formula: see text]nm) near-infrared (NIR) emitting AuNPs that are coated with zwitterionic glutathione and neutral polyethylene glycol (PEG) ligands, respectively, we found that zwitterionic glutathione coated AuNPs (GS-AuNPs) can reduce survival rates of MCF-7 cells under irradiation of clinically used megavoltage photon beam at low dosage of [Formula: see text][Formula: see text]Gy. On the other hand, PEG-AuNPs can serve as a radiation-protecting agent and enabled MCF-7 cells more resistant to the irradiation, clearly indicating the key role of surface chemistry in radiosensitization of AuNPs. More detailed studies suggested that such difference was independent of cellular uptake and its efficiency, but might be related to the ligand-induced difference in photoelectron generation and/or interactions between AuNPs and X-ray triggered reactive oxygen species (ROS).

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Dosimetry and Radioenhancement Comparison of Gold Nanoparticles in Kilovoltage and Megavoltage Radiotherapy using MAGAT Polymer Gel Dosimeter

Journal of Biomedical Physics and Engineering ◽

10.31661/jbpe.v9i2apr.827 ◽

2019 ◽

Vol 9 (2Apr) ◽

Cited By ~ 1

Author(s):

S Farahani ◽

N Riyahi Alam ◽

S Haghgoo ◽

M Khoobi ◽

Gh Geraily ◽

...

Keyword(s):

Gold Nanoparticles ◽

3D Visualization ◽

Energy Levels ◽

Polymer Gel ◽

External Radiotherapy ◽

Dose Enhancement ◽

Internal Radiotherapy ◽

Boost Radiotherapy

Background: Numerous unique characteristics of the nanosized gold, including high atomic number, low toxicity, and high biocompatibility make it one of the most appropriate nanostructures to boost radiotherapy efficacy. Many in-vivo and in-vitro investigations have indicated that gold nanoparticles (AuNPs) can significantly increase tumor injuries in low kilovoltage radiotherapy. While deep-lying tumors require much higher energy levels with greater penetration power, and investigations carried out in megavoltage energy range show contradictory results.Objective: In this study, we quantitatively assess and compare dose enhancement factors (DEFs) obtained through AuNPs under radiation of Cobalt-60 source (1.25MeV) versus Iridium-192 source (0.380 KeV) using MAGAT gel dosimeter.Material and Methods: MAGAT polymer gel in both pure and combined with 0.2 mM AuNPs was synthesized. In order to quantify the effect of energy on DEF, irradiation was carried out by Co-60 external radiotherapy and Ir-192 internal radiotherapy. Finally, readings of irradiated and non-irradiated gels were performed by MR imaging.Result: The radiation-induced R2 (1/T2) changes of the gel tubes doped with AuNPs compared to control samples, upon irradiation of beams released by Ir-192 source showed a significant dose enhancement (15.31% ±0.30) relative to the Co-60 external radiotherapy (5.85% ±0.14).Conclusion: This preliminary study suggests the feasibility of using AuNPs in radiation therapy (RT), especially in low-energy sources of brachytherapy. In addition, MAGAT polymer gel, as a powerful dosimeter, could be used for 3D visualization of radiation dose distribution of AuNPs in radiotherapy.

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Synthesis of Novel 3(N,N-dialkylamino)alkyl/phenyl Substituted Thieno [2,3-d]pyrimidinones as H1-Anti-Histaminic and Antimicrobial Agents

Current Bioactive Compounds ◽

10.2174/1573407214666180226130957 ◽

2019 ◽

Vol 15 (1) ◽

pp. 63-70

Author(s):

Shiv Dev Singh ◽

Arvind Kumar ◽

Firoz Babar ◽

Neetu Sachan ◽

Arun Kumar Sharma

Keyword(s):

Antimicrobial Activity ◽

Potassium Hydroxide ◽

Antimicrobial Agents ◽

Pyrimidine Ring ◽

Antimicrobial Activities ◽

Screening Methods ◽

Chlorpheniramine Maleate ◽

In Vivo Screening

Background: Thienopyrimidines are the bioisoster of quinazoline and unlike quinazoline exist in three isomeric forms corresponding to the three possible types annulation of thiophene to the pyrimidine ring viz thieno[2,3-d] pyrimidine, thieno[3,2-d] pyrimidine and thieno[3,4-d]pyrimidine. Heterocyclic containing the thienopyrimidinone moiety exhibits various pronounced activities such as anti-hypertensive, analgesic and anti-inflammatory, antiviral, platelet aggregation inhibitory, antiprotozoal bronchodilatory, phosphodiesterase inhibitory, antihistaminic, antipsychotic and antimicrobial activity. Objective: Synthesis of novel 3(N,N-dialkylamino)alkyl/phenyl substituted thieno[2,3-d]pyrimidinones as H1-anti-histaminic and antimicrobial agents. Methods: A series of 3-[(N,N-dialkylamino)alkyl/phenyl]-2-(1H)thioxo-5,6,7,8-tetrahydrobenzo(b) thieno(2,3-d)pyrimidine-4(3H)-ones[4a-d], their oxo analogous [5a-d] and 3-[(N,N-dialkylamino)alkyl]- 2-chlorophenyl-5,6,7,8-tetrahydrobenzo(b)thieno(2,3-d)pyrimidine- 4 (3H)-ones[6a-d]derivative were synthesized from 2-amino-4,5,6,7-tetrahydrobenzo(b)thiophene-3-carboxylic acid by nucleophilic substitution of different N,N-dialkyl alkylene/phenylene diamines on activated 3-acylchloride moiety followed by cyclocondensation with carbon disulfide and ethanolic potassium hydroxide to get [4a-d] and in second reaction by condensation with 4-chlorobenzoyl chloride to get [6a-d] by single pot novel innovative route. The oxo analogous [5a-d] were prepared by treating derivatives [4a-d] with potassium permagnate in ethanolic KOH. The synthesized compound were evaluated for H1-antihistaminic and antimicrobial activities. Results: All synthesized compounds exhibited significant H1-antihistaminic activity by in vitro and in vivo screening methods and data were verified analytically and statistically. The compound 4a, 4b, 5a and 5b showed significant H1-antihistaminiic activity than the reference standard chlorpheniramine maleate. The compound 6d, 6c, 5c and 4c exhibited significant antimicrobial activity.

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