Optimization of Gold Nanoparticles Synthesis using Design of Experiments Technique

Gold nanoparticles are considered the newest drug carriers for different diseases. Therefore it is appropriate continuous optimization of their preparation. In this study, gold colloids with an average size of 1 - 26 nm were obtained by the reduction of tetrachloroauric acid with trisodium citrate. The nanomaterials were characterized by UV-Vis spectroscopy and dynamic light scattering technique. In addition, zeta potential was measured for samples synthesized in order to determine the stability of the colloids. A Two-level Full Factorial design was chosen to determine the optimum set of process parameters (chloroauric acid concentration and sodium citrate concentration) and their effect on various gold nanoparticles characteristics (size and zeta potential). These effects were quantified using Design of Experiments (DoE) with 5 runs and 1 centerpoint. The selected objective and process model in this investigation are screening and interaction. Findings from this research show that to obtain particles larger than 35 nm, it is recommended to increase sodium citrate concentration, at low chloroauric acid values. These conditions will help to achieve smaller zeta potential, too.

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Seed-mediated synthesis and PEG coating of gold nanoparticles for controlling morphology and sizes

MRS Advances ◽

10.1557/adv.2020.416 ◽

2020 ◽

Vol 5 (63) ◽

pp. 3353-3360

Author(s):

Susana Helena Arellano Ramírez ◽

Perla García Casillas ◽

Christian Chapa González

Keyword(s):

Gold Nanoparticles ◽

Polyethylene Glycol ◽

Room Temperature ◽

Colloidal Stability ◽

Infrared Spectrometry ◽

Ammonium Bromide ◽

Chloroauric Acid ◽

Vis Spectroscopy ◽

Seed Mediated ◽

Peg Coating

AbstractA significant area of research is biomedical applications of nanoparticles which involves efforts to control the physicochemical properties through simple and scalable processes. Gold nanoparticles have received considerable attention due to their unique properties that they exhibit based on their morphology. Gold nanospheres (AuNSs) and nanorods (AuNRs) were prepared with a seed-mediated method followed of polyethylene glycol (PEG)-coating. The seeds were prepared with 0.1 M cetyltrimethyl-ammonium bromide (CTAB), 0.005 M chloroauric acid (HAuCl4), and 0.01 M sodium borohydride (NaBH4) solution. Gold nanoparticles with spherical morphology was achieved by growth by aggregation at room temperature, while to achieve the rod morphology 0.1 M silver nitrate (AgNO3) and 0.1 M ascorbic acid solution were added. The gold nanoparticles obtained by the seed-mediated synthesis have spherical or rod shapes, depending on the experimental conditions, and a uniform particle size. Surface functionalization was developed using polyethylene glycol. Morphology, and size distribution of AuNPs were evaluated by Field Emission Scanning Electron Microscopy. The average size of AuNSs, and AuNRs was 7.85nm and 7.96 x 31.47nm respectively. Fourier transform infrared spectrometry was performed to corroborate the presence of PEG in the AuNPs surface. Additionally, suspensions of AuNSs and AuNRs were evaluated by UV-Vis spectroscopy. Gold nanoparticles were stored for several days at room temperature and it was observed that the colloidal stability increased once gold nanoparticles were coated with PEG due to the shield formed in the surface of the NPs and the increase in size which were 9.65±1.90 nm of diameter for AuNSs and for AuNRs were 29.03±5.88 and 8.39±1.02 nm for length and transverse axis, respectively.

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Controlled Synthesis of Gold Nanoparticles UsingAspergillus terreusIF0 and Its Antibacterial Potential against Gram Negative Pathogenic Bacteria

Journal of Nanotechnology ◽

10.1155/2014/653198 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 14

Author(s):

Eepsita Priyadarshini ◽

Nilotpala Pradhan ◽

Lala B. Sukla ◽

Prasanna K. Panda

Keyword(s):

Gold Nanoparticles ◽

Pathogenic Bacteria ◽

Particle Diameter ◽

Weight Fraction ◽

Xrd Analysis ◽

Controlled Synthesis ◽

Chloroauric Acid ◽

Gram Negative ◽

Fungal Extract ◽

Vis Spectroscopy

Biosynthesis of monodispersed nanoparticles, along with determination of potential responsible biomolecules, is the major bottleneck in the area of bionanotechnology research. The present study focuses on an ecofriendly, ambient temperature protocol for size controlled synthesis of gold nanoparticles, using the fungusAspergillus terreusIF0. Gold nanoparticles were formed immediately, with the addition of chloroauric acid to the aqueous fungal extract. Synthesized nanoparticles were characterized by UV-Vis spectroscopy, TEM-EDX, and XRD analysis. Particle diameter and dispersity of nanoparticles were controlled by varying the pH of the fungal extract. At pH 10, the average size of the synthesized particles was in the range of 10–19 nm. Dialysis to obtain high and low molecular weight fraction followed by FTIR analysis revealed that biomolecules larger than 12 kDa and having –CH, –NH, and –SH functional groups were responsible for bioreduction and stabilization. In addition, the synthesized gold nanoparticles were found to be selectively bactericidal against the pathogenic gram negative bacteria,Escherichia coli.

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Hybrid Microgels Containing Gold Nanoparticles

e-Polymers ◽

10.1515/epoly.2006.6.1.226 ◽

2006 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

Andrij Pich ◽

Arpita Karak ◽

Yan Lu ◽

Anup K. Ghosh ◽

Hans-Juergen P. Adler

Keyword(s):

Gold Nanoparticles ◽

Sodium Citrate ◽

Colloidal Stability ◽

Nano Particles ◽

Composite Particles ◽

Temperature Sensitive ◽

Chloroauric Acid ◽

Gold Nano Particles ◽

Hybrid Microgels

AbstractIn present paper we report on a preparation of hybrid microgels filled with gold nano-particles (AuNPs). Temperature-sensitive VCL/AAEM microgels have been used as containers for deposition of Au by in situ formation of gold nano-particles. Synthesis of AuNPs has been performed by two methods: a) reduction of chloroauric acid with sodium borhydride and b) reduction of chloroauric acid by sodium citrate under ultrasonic agitation. In both cases AuNPs were deposited directly into microgels leading to formation of composite particles which exhibit temperature-sensitive properties, tunable gold contents and high colloidal stability. The influence of Au load on microgel size, morphology, swellingdeswelling behaviour and stability is discussed.

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Formation of Gold Nanoparticles Film on Silicon Wafer by Self-Assembled Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.795.726 ◽

2013 ◽

Vol 795 ◽

pp. 726-731 ◽

Cited By ~ 1

Author(s):

Khatijah A. Yaacob ◽

Gooi Wyn Gyn

Keyword(s):

Particle Size ◽

Gold Nanoparticles ◽

Surface Morphology ◽

Silicon Wafer ◽

Sodium Citrate ◽

Chemical Reduction ◽

Wafer Surface ◽

Gold Colloid ◽

Gold Colloids ◽

Self Assembled

The gold nanoparticles film has been successfully formed on the silicon wafer by self-assembled method. The gold colliods were prepared by chemical reduction method where sodium citrate (act as the reducing, capping and stabilizing agent) were added into the boiling 50ml of 0.01% tetrachloroauria acid (HAuCl4) solution in reflux system. Different particle size of gold colloids (AuNPs_1 and AuNPs_2) were produced by altering the amount of sodium citrate. The as-prepared gold colloids were characterized by UV - Vis spectrometry, Malvern particle size analyzer, zeta potential and XRD. Self-assembled method of Au nanoparticles were first start with the cleaning of silicon wafers using standard RCA cleaning, and followed by the piranha treatment to producing an OH-terminated surface. Then, the wafers were functionalized with organosilane molecule by immersing the silicon wafer in 10mM of surfactant in methanolic solution to produce self-assemble monolayers (SAMs) on silicon wafer surface. These layers were used to immobilize the gold nanoparticles from as-prepared gold colloid and result of the gold nanoparticles film on silicon wafer. Effect of surfactant ((3-aminopropyl) trimethoxysilane (APTMS) and (3-mercaptopropyl) trimethoxysilane (MPTMS)), effect of particle size of gold colloid (AuNPs_1 and AuNPs_2) and the effect of deposition time (0.5, 1.0, 1.5 and 2 hours) to the surface morphology such as surface coverage, inter-particle distance were studied in this work. The surface morphology of gold nanoparticles films were characterized by FESEM and AFM.

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Role of Surfactant in the Formation of Gold Nanoparticles in Aqueous Medium

Journal of Nanoparticles ◽

10.1155/2014/916429 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 14

Author(s):

Abhishek Das ◽

Ridhima Chadha ◽

Nandita Maiti ◽

Sudhir Kapoor

Keyword(s):

Gold Nanoparticles ◽

Aqueous Medium ◽

Sodium Dodecyl ◽

Chloroauric Acid ◽

Synthesis Mechanism ◽

Transmission Electron ◽

Vis Spectroscopy ◽

The Stability ◽

Mediated Reduction

The stability of gold nanoparticles is a major issue which decides their impending usage in nanobiotechnological applications. Often biomimetically synthesized nanoparticles are deemed useless owing to their instability in aqueous medium. So, surfactants are used to stabilize the nanoparticles. But does the surfactant only stabilize by being adsorbed to the surface of the nanoparticles and not play significantly in moulding the size and shape of the nanoparticles? Keeping this idea in mind, gold nanoparticles (GNPs) synthesized by l-tryptophan (Trp) mediated reduction of chloroauric acid (HAuCl4) were stabilized by anionic surfactant, sodium dodecyl sulphate (SDS), and its effect on the moulding of size and properties of the GNPs was studied. Interestingly, unlike most of the gold nanoparticles synthesis mechanism showing saturation growth mechanism, inclusion of SDS in the reaction mixture for GNPs synthesis resulted in a bimodal mechanism which was studied by UV-Vis spectroscopy. The mechanism was further substantiated with transmission electron microscopy. Zeta potential of GNPs solutions was measured to corroborate stability observations recorded visually.

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The Influence of the Peptide Molar Ratios on the Functionalization of Gold Nanoparticles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.872.94 ◽

2013 ◽

Vol 872 ◽

pp. 94-105

Author(s):

Mayra C. Ramirez-Camacho ◽

Inga Tuzovskaya ◽

Nina Bogdanchikova ◽

Alexey Pestryakov ◽

Arturo Susarrey-Arce ◽

...

Keyword(s):

Particle Size ◽

Gold Nanoparticles ◽

Particle Size Distribution ◽

Size Distribution ◽

Sodium Citrate ◽

Red Shift ◽

Molar Ratio ◽

Narrow Particle Size Distribution ◽

Plasmon Peak ◽

Vis Spectroscopy

Au nanoparticles (NPs) functionalized with L-cysteine (Cys) and cysteine-glycine (Cys-Gly) were synthetized. The AuNPs were prepared using sodium citrate as reducing agent. The influence of the molar concentrations of Cys and Cys-Gly, as well as the sodium citrate is studied on particle size and particle size distribution. TEM measurements revealed the formation of AuNPs with diameter in the range 5-35 nm which corresponds to nontoxic sizes [we should add a reference here, perhaps number one]. The optimal particle size for biomedical application along with narrow particle size distribution was observed for samples prepared with molar ratio of CAu:Ccitrate = 1:10. The results of UV-Vis spectroscopy revealed the interaction of the AuNPs with Cys and Gly-Cys demonstrated by a visible change in the absorption intensities of the plasmon peak located at 520 nm after AuNP functionalization and a slight shifting of this gold nanoparticles plasmon peak. Thus, any dielectric shell on surface of particles with more refraction index (and, correspondingly, dielectric function) can produce the particles with the red shift. Such effect of the surface shell with red-shift in the range of few nanometers observed for the AuNPs functionalized with Cys and Cys-Gly (Fig. 4) can be interpreted as thin or discontinuous layer of aminoacid molecules according to the data of optical spectra simulation.

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Shape-Controlled Generation of Gold Nanoparticles Assisted by Dual-Molecules: The Development of Hydrogen Peroxide and Oxidase-Based Biosensors

Journal of Nanomaterials ◽

10.1155/2014/576082 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Chifang Peng ◽

Xiaohui Duan ◽

Zhengjun Xie ◽

Chunli Liu

Keyword(s):

Gold Nanoparticles ◽

Sodium Citrate ◽

Chloroauric Acid ◽

One Pot ◽

Naked Eye ◽

Different Shapes ◽

Shape Controlled ◽

Ethanesulfonic Acid ◽

Mediated Reduction ◽

Anisotropic Metal

With the assist of dual-molecules, 2-(N-morpholino)ethanesulfonic acid (MES) and sodium citrate, gold nanoparticles (GNPs) with different shapes can be generated in the H2O2-mediated reduction of chloroauric acid. This one-pot reaction can be employed to sensitively detect H2O2, probe substrates or enzymes in oxidase-based reactions as well as prepare branched GNPs controllably. By the “naked eye,” 20 μM H2O2, 0.1 μM glucose, and 0.26 U/mL catalase could be differentiated, respectively. By spectrophotometer, the detected limits of H2O2, glucose, and catalase were 1.0 μM, 0.01 μM, and 0.03 U/mL, respectively, and the detection linear ranges for them were 5.0–400 μM, 0.01–0.3 mM, and 0.03–0.78 U/mL, respectively. The proposed “dual-molecules assist” strategy probably paves a new way for the fabrication of nanosensors based on the growth of anisotropic metal nanoparticles, and the developed catalase sensor can probably be utilized to fabricate ultrasensitive ELISA methods for various analytes.

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Synthesis of L-Phenylalanine Stabilized Gold Nanoparticles and Their Thermal Stability

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2006.17972 ◽

2006 ◽

Vol 6 (11) ◽

pp. 3512-3516 ◽

Cited By ~ 1

Author(s):

Nimai C. Nayak ◽

Kwanwoo Shin

Keyword(s):

Thermal Stability ◽

Gold Nanoparticles ◽

Electron Microscope ◽

Ambient Condition ◽

Synthesis Methods ◽

Chloroauric Acid ◽

Borohydride Reduction ◽

Thermal Stabilities ◽

Transmission Electron ◽

Vis Spectroscopy

Here we described the two synthesis methods of L-phenylalanine (L-phe) coated gold nanoparticles through a reduction of aqueous chloroaurate ions directly by L-phe, and also the borohydride reduction of chloroauric acid followed by capping with L-phe molecules. Phenylalanine reduced gold nanoparticles and the phenylalanine capped gold nanoparticles were evaluated by transmission electron microscope and UV-vis spectroscopy, and then their thermal stabilities were compared. We found that the phenylalanine reduced gold nanoparticles were unstable and form linearly arranged aggregates on aging, while as the phenylalanine capped gold nanoparticles were stable for months in ambient condition.

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Study on Synthesis and Catalysis Application of Nano-Au/C Catalyst

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.636.15 ◽

2014 ◽

Vol 636 ◽

pp. 15-18

Author(s):

Zi Jing Li ◽

Yan Jiang ◽

Li Da Sun ◽

Shao Ping Feng ◽

Rui Min Xiao ◽

...

Keyword(s):

Gold Nanoparticles ◽

Catalytic Activity ◽

Liquid Phase ◽

Oxidation Reaction ◽

Sodium Citrate ◽

Preparation Method ◽

Colloidal Gold Nanoparticles ◽

Vis Spectroscopy ◽

Size And Morphology ◽

Size Controlled

The size controlled colloidal gold nanoparticles were prepared by sodium citrate photochemical system. The size and morphology of the gold nanoparticles were characterized by TEM and UV-Vis spectroscopy. nanoAu/C catalysts were obtained by loading the gold nanoparticles. The catalysts were used for the catalytic oxidation reaction of glyoxal and glucose in liquid phase. The research results showed that the catalysts had higher catalytic activity, and this preparation method is successful.

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CONTROLLING THE SIZE AND SIZE DISTRIBUTION OF GOLD NANOPARTICLES: A DESIGN OF EXPERIMENT STUDY

International Journal of Nanoscience ◽

10.1142/s0219581x12500238 ◽

2012 ◽

Vol 11 (02) ◽

pp. 1250023 ◽

Cited By ~ 17

Author(s):

DHIRAJ KUMAR ◽

BRIAN J MEENAN ◽

ISHA MUTREJA ◽

RAECHELLE D'SA ◽

DORIAN DIXON

Keyword(s):

Gold Nanoparticles ◽

Size Distribution ◽

Design Of Experiment ◽

Metallic Nanoparticles ◽

Sodium Citrate ◽

Chloroauric Acid ◽

Production Volume ◽

Synthesis Of Nanoparticles ◽

Potential Applications ◽

Poly Ethylene

The Turkevich method is the oldest and most widely employed protocol for the production of colloidal gold. Gold nanoparticles are nontoxic in nature and have potential applications in various biomedical fields including drug delivery and bioimaging. These metallic nanoparticles can be functionalized with drugs, targeting ligands such as tumor necrosis factor and groups (e.g., Poly ethylene glycol) to provide shielding from undesired immune responses. In this study we investigate the influence of process variables on the synthesis of nanoparticles by the reduction of chloroauric acid ( HAuCl4 ) solution with sodium citrate. A design of experiment (DoE) approach was used to investigate the influence of production volume, temperature, stirring rate and sodium citrate concentration on the physical properties of the nanoparticles namely size, size distribution, zeta potential and UV-Vis characteristics. The study showed that the relative amount of sodium citrate added ( Au /citrate mole ratio) had a significant effect on the size, poly dispersity index (PDI), the number of peaks in the size distribution and the position of Lambda max in the UV-Vis spectra. By varying the Au /Citrate ratio it is possible to synthesize particles with average diameters from 20 to 80 nm. However, the use of low amounts of sodium citrate in order to produce particles larger than ~35 nm tends to result in a wide bimodal size distribution.

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