scholarly journals Size and macromolecule stabilizer–dependent performance of gold colloids in immuno-PCR

2022 ◽  
Author(s):  
Mahdis Sadat Tabatabaei ◽  
Rafiq Islam ◽  
Marya Ahmed
Keyword(s):  
Gold Colloids

Optimization of Gold Nanoparticles Synthesis using Design of Experiments Technique

2017 ◽  
Vol 68 (7) ◽  
pp. 1518-1423
Author(s):  
Adina Turcu Stiolica ◽  
Mariana Popescu ◽  
Maria Viorica Bubulica ◽  
Carmen Nicoleta Oancea ◽  
Claudiu Nicolicescu ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Zeta Potential ◽  
Design Of Experiments ◽  
Process Model ◽  
Sodium Citrate ◽  
Drug Carriers ◽  
Chloroauric Acid ◽  
Gold Colloids ◽  
Citrate Concentration ◽  
Vis Spectroscopy

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.

Anisometric gold colloids. Preparation, characterization, and optical properties

1989 ◽  
Vol 157 (6) ◽  
pp. 569-575 ◽  
Author(s):  
J. Wiesner ◽  
A. Wokaun
Keyword(s):  
Optical Properties ◽  
Gold Colloids

Plasma resonance - enhanced raman scattering by adsorbates on gold colloids: The effects of aggregation

1982 ◽  
Vol 120 (2) ◽  
pp. A339 ◽  
Author(s):  
C.G. Blatchford ◽  
J.R. Campbell ◽  
J.A. Creighton
Keyword(s):  
Raman Scattering ◽  
Plasma Resonance ◽  
Gold Colloids ◽  
Enhanced Raman Scattering

Comment on ‘‘Limits of the fractal dimension for irreversible kinetic aggregation of gold colloids’’

1987 ◽  
Vol 58 (10) ◽  
pp. 1051-1051 ◽  
Author(s):  
Jess P. Wilcoxon ◽  
James E. Martin ◽  
Dale W. Schaefer
Keyword(s):  
Fractal Dimension ◽  
Gold Colloids

Enhancing the electrochromic properties of polyaniline via coordinate bond tethering the polyaniline with gold colloids

2018 ◽  
Vol 177 ◽  
pp. 134-141 ◽  
Author(s):  
Shanxin Xiong ◽  
Jinpeng Lan ◽  
Siyuan Yin ◽  
Yuyun Wang ◽  
Zhenzhen Kong ◽  
...  
Keyword(s):  
Gold Colloids ◽  
Electrochromic Properties ◽  
Coordinate Bond

scholarly journals In situ structural kinetics of picosecond laser-induced heating and fragmentation of colloidal gold spheres

2020 ◽  
Vol 22 (9) ◽  
pp. 4993-5001 ◽  
Author(s):  
Anna Rosa Ziefuss ◽  
Stefan Reich ◽  
Sven Reichenberger ◽  
Matteo Levantino ◽  
Anton Plech
Keyword(s):  
Colloidal Gold ◽  
Picosecond Laser ◽  
Time Resolved ◽  
Gold Colloids ◽  
X Ray ◽  
X Ray Scattering ◽  
Kinetics Of ◽  
Ray Scattering

The structural and energetic pathway of picosecond laser fragmentation of gold colloids has been clarified by time-resolved X-ray scattering.

scholarly journals Examination of Adsorption Orientation of Amyloidogenic Peptides Over Nano-Gold Colloidal Particle Surfaces

2019 ◽  
Vol 20 (21) ◽  
pp. 5354 ◽  
Author(s):  
Kazushige Yokoyama ◽  
Kieran Brown ◽  
Peter Shevlin ◽  
Jack Jenkins ◽  
Elizabeth D’Ambrosio ◽  
...  
Keyword(s):  
Charge Distribution ◽  
Size Dependence ◽  
Partial Charge ◽  
Gold Colloid ◽  
Gold Colloids ◽  
Nano Gold ◽  
Secondary Layer ◽  
Amyloidogenic Peptides ◽  
The Difference ◽  
Nano Size

The adsorption of amyloidogenic peptides, amyloid beta 1–40 (Aβ1–40), alpha-synuclein (α-syn), and beta 2 microglobulin (β2m), was attempted over the surface of nano-gold colloidal particles, ranging from d = 10 to 100 nm in diameter (d). The spectroscopic inspection between pH 2 and pH 12 successfully extracted the critical pH point (pHo) at which the color change of the amyloidogenic peptide-coated nano-gold colloids occurred due to aggregation of the nano-gold colloids. The change in surface property caused by the degree of peptide coverage was hypothesized to reflect the ΔpHo, which is the difference in pHo between bare gold colloids and peptide coated gold colloids. The coverage ratio (Θ) for all amyloidogenic peptides over gold colloid of different sizes was extracted by assuming Θ = 0 at ΔpHo = 0. Remarkably, Θ was found to have a nano-gold colloidal size dependence, however, this nano-size dependence was not simply correlated with d. The geometric analysis and simulation of reproducing Θ was conducted by assuming a prolate shape of all amyloidogenic peptides. The simulation concluded that a spiking-out orientation of a prolate was required in order to reproduce the extracted Θ. The involvement of a secondary layer was suggested; this secondary layer was considered to be due to the networking of the peptides. An extracted average distance of networking between adjacent gold colloids supports the binding of peptides as if they are “entangled” and enclosed in an interfacial distance that was found to be approximately 2 nm. The complex nano-size dependence of Θ was explained by available spacing between adjacent prolates. When the secondary layer was formed, Aβ1–40 and α-syn possessed a higher affinity to a partially negative nano-gold colloidal surface. However, β2m peptides tend to interact with each other. This difference was explained by the difference in partial charge distribution over a monomer. Both Aβ1–40 and α-syn are considered to have a partial charge (especially δ+) distribution centering around the prolate axis. The β2m, however, possesses a distorted charge distribution. For a lower Θ (i.e., Θ <0.5), a prolate was assumed to conduct a gyration motion, maintaining the spiking-out orientation to fill in the unoccupied space with a tilting angle ranging between 5° and 58° depending on the nano-scale and peptide coated to the gold colloid.

Sign in / Sign up

Export Citation Format

Share Document