Preparation of monodispersed carboxylate-functionalized gold nanoparticles using pamoic acid as a reducing and capping reagent

Aziz, Md. Abdul; Kim, Jong-Pil; Oyama, Munetaka

doi:10.1007/s13404-014-0134-0

Cited by 26 publications

(19 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Modifying the size of PA-capped AuNPs in a controlled manner, however, was not explored in our earlier work [21]. Therefore, one of the aims for the present work was to control the sizes of AuNPs during the chemical preparation with PA. We found that the amount of NaOH, i.e., pH, affected their average size.…”

Section: Structurementioning

confidence: 95%

“…Another aim of the currently reported work was to show the fluorescence properties of PA-capped AuNPs, which had not been described in our previous work [21]. Since PA is a fluorescent molecule [22], capping with PA is expected to provide significant fluorescence properties to AuNPs in addition to providing the carboxylate functional groups.…”

Section: Structurementioning

confidence: 96%

“…We previously reported a simple method for the preparation of AuNPs using pamoic acid (PA; 4,4′-methylene-bis(3-hydroxy-2-naphthalene carboxylic acid) (structure 1) with NaOH at room temperature [21]. Although PA is insoluble in water, it can be dissolved in the presence of NaOH and functions as a capping and reducing reagent to form AuNPs.…”

Section: Structurementioning

confidence: 99%

“…The original PA-capped AuNPs were synthesized according to our earlier report [21]. Briefly, a clear solution of 2 mM disodium salt of PA (Na 2 -PA) was prepared by sonication of 7.9 mg of PA and 40 μl of 1.0 M NaOH (aq.)…”

Section: Synthesis Of Aunp By Controlling the Alkalimentioning

confidence: 99%

See 3 more Smart Citations

Size-controlled preparation of fluorescent gold nanoparticles using pamoic acid

et al. 2015

Self Cite

View full text Add to dashboard Cite

We previously showed that pamoic acid (PA) could be utilized as a reducing and capping reagent for preparing monodispersed gold nanoparticles (AuNPs) with diameters of 10.8 nm. Here, we show that the size of these PA-capped AuNPs can be varied in a controlled manner by changing the pH used in the preparation process. By changing the added amount of NaOH in the PA solution before mixing with HAuCl 4 , several types of AuNPs were prepared at different pH values. The absorption spectra showed a red shift of the characteristic peak of the AuNPs with decreasing pH, indicating the formation of larger AuNPs. The TEM results confirmed this relationship between AuNP size and pH, and the zeta potentials indicated that the AuNPs capped with PA were more stable than the AuNPs prepared by citrate reduction method. Furthermore, the PA-capped AuNPs showed much higher fluorescence intensities than those of citrate-capped AuNPs, which is due to the fluorescence of PA. The sizes of PA-capped spherical AuNPs could also be controlled by a seed-mediated growth approach. However, the original PAcapped AuNPs, with diameters of 10.8 nm, exhibited the highest fluorescence intensities among the various types of PA-capped AuNPs that were grown. In addition to conferring fluorescence properties to the AuNPs, the capping by PA also provided the nanoparticles with carboxylate groups.

show abstract

Section: Structurementioning

confidence: 95%

Section: Structurementioning

confidence: 96%

Section: Structurementioning

confidence: 99%

Section: Synthesis Of Aunp By Controlling the Alkalimentioning

confidence: 99%

See 2 more Smart Citations

Size-controlled preparation of fluorescent gold nanoparticles using pamoic acid

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…12 In addition, methodological development of the preparation for monodispersed AuNPs would be important. 13 Although certain sized AuNPs have been successfully modified on electrode surfaces in general, we are interested in fundamental aspects of the attachment of AuNPs whose sizes are different. Actually, we are interested in determining what happens if two different sized AuNPs are present in a solution in which AuNPs are linked with the bridging reagent and attached competitively.…”

Section: Introductionmentioning

confidence: 99%

Competitive Attachment of Gold Nanoparticles on an Indium Tin Oxide Electrode

Oyama

Fujita

2015

ANAL. SCI.

Self Cite

View full text Add to dashboard Cite

Fundamental aspects of the attachment of gold nanoparticles (AuNPs) onto a 3-aminopropyltrimethoxysilane (APTMS) modified indium tin oxide (ITO) electrode were explored using commercially available Au colloid solutions of 5, 10 and 20 nm. In particular, competitive attachments of AuNPs were observed using mixed solutions of two Au colloids. Consequently, it was found that smaller AuNPs are easily attached on an APTMS modified ITO. On the other hand, the result of the stepwise attachments showed that after the surface was modified by the first AuNPs, the second AuNPs have difficulty attaching. This means, if surface connecting -NH2 terminals of APTMS are once occupied, further modification or exchange of the attached AuNPs would not be easy. From the present results, a contaminant amount of smaller AuNPs is considered to be a practical problem in modifying ITO surfaces by AuNPs.

show abstract

Preparation and Application of Microelectrodes at the Single‐Molecule Scale

Gao

Liu

Zhang

et al. 2021

Chemistry An Asian Journal

View full text Add to dashboard Cite

Molecular electronics offers a potential solution for the miniaturization of electronics beyond conventional silicon electronics. A key goal of molecular electronics is to fabricate the single‐molecule junction with the functions of electronic units. The term “molecular junction” means a molecular cluster or a single molecule incorporated between two microelectrodes, and electrons are transported across it. The methods of constructing molecular junctions dynamically were developed, such as STM‐BJ, AFM‐BJ, and MCBJ, providing precise control of the gap and easy measurement of thousands of junctions. Electrodes based on these techniques are commonly called microelectrodes because at least one dimension is on the micron scale. In this manuscript, we summarize the preparation methods of microelectrodes and their application in single‐molecule measurements. In addition, we discuss the electrode factor that influences the molecular electrical properties, such as material, curvature radius and cone angle, and further provide a brief prospect of molecular electronics.

show abstract

Preparation of monodispersed carboxylate-functionalized gold nanoparticles using pamoic acid as a reducing and capping reagent

Cited by 26 publications

References 26 publications

Size-controlled preparation of fluorescent gold nanoparticles using pamoic acid

Size-controlled preparation of fluorescent gold nanoparticles using pamoic acid

Competitive Attachment of Gold Nanoparticles on an Indium Tin Oxide Electrode

Preparation and Application of Microelectrodes at the Single‐Molecule Scale

Contact Info

Product

Resources

About