Heavy-metal ion sensors using chitosan-capped gold nanoparticles

Sugunan, Abhilash; Thanachayanont, Chanchana; Dutta, Joydeep; Hilborn, Jöns

doi:10.1016/j.stam.2005.03.007

Cited by 298 publications

(131 citation statements)

References 19 publications

Supporting

Mentioning

123

Contrasting

Unclassified

Order By: Relevance

“…1a, UV-visible absorption spectrum for Au colloid consisting of 1 lM GNPs in the presence of 40 g/L PVP molecules in 1-butanol displayed a strong peak at 526 nm ascribed to surface plasmon resonance (SPR) band (Eustis and El-Sayed 2006;Sugunan et al 2005;Ram and Fecht 2011;Behera and Ram 2012a, b). Whereas absorption spectrum of 1 lM uncapped-GNPs (i.e., without PVP molecules) in 1-butanol exhibits a somewhat redshifted and broad SPR band at 533 nm with a half width at full maximum (HWFM) *65 nm shown in the inset of Fig.…”

Section: Uv-visible and Xps Spectrummentioning

confidence: 99%

“…An organic solvent was chosen in this work because such medium founds to provide low interfacial energies needed for a high degree of control during solution and surface processing is required for synthesis of nano colloids (Balasubramaniam et al 2002). Also it was reported that Au-NPs synthesized in an organic medium offer excellent control over size and possess superior processability (Sugunan et al 2005). …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Intense quenching of fluorescence intensity of poly(vinyl pyrrolidone) molecules in presence of gold nanoparticles

Behera

Ram

2012

Appl Nanosci

View full text Add to dashboard Cite

We study the quenching of fluorescence intensity of 40 g/L poly(vinyl pyrrolidone) PVP molecules by varying the content of gold nanoparticles (GNPs) from 1 to 5 lM in 1-butanol. A profound exponential decay of the emission band intensity in the p / np* band of the PVP molecules at *392 nm upon gradual addition of the GNPs demonstrates an existence of an excited state interaction of NPs with the PVP molecules in a gold colloid in 1-butanol. Such quenching is caused by the non-bonding electron transfer from the O-atom of carbonyl group of the PVP molecules to the surface of the GNP. X-ray photoemission spectroscopy (XPS) study corroborates the spectroscopic results. A linear Stern-Volmer plot with a quenching constant of 2.23 9 10 6 M -1 reveals dynamic quenching in a non-aqueous NF. A mechanism of fluorescence quenching was proposed in support of XPS and images taken from hybrid nanostructure using transmission electron microscope. Study on quenching of fluorescence intensity of PVP fluorophore in the presence of GNPs is useful for optoelectronic devices and biosensors.

show abstract

Section: Uv-visible and Xps Spectrummentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Intense quenching of fluorescence intensity of poly(vinyl pyrrolidone) molecules in presence of gold nanoparticles

Behera

Ram

2012

Appl Nanosci

View full text Add to dashboard Cite

show abstract

“…Again, an organic solvent found to provide low interfacial energies is needed for a high degree of control during solution and surface processing [17]. Also, Au NPs synthesized in an organic medium offer excellent control and uniformity of size and possess exceptional processability [39]. The interaction between Au NPs and PVP molecules in 1-butanol has been studied by using UV-visible spectroscopy, FTIR spectroscopy, emission spectroscopy, XPS, zeta potential, and transmission electron microscopy.…”

Section: Introductionmentioning

confidence: 99%

Spectroscopy-based study on the interaction between gold nanoparticle and poly(vinylpyrrolidone) molecules in a non-hydrocolloid

Behera

Ram

2013

Int Nano Lett

View full text Add to dashboard Cite

The study of the interaction between poly(vinylpyrrolidone) (PVP) and gold (Au) nanoparticles (NPs) in a colloid is of special interest for possible applications in the field of catalysis, biosensing, and biomedicine. A strong optical absorption arising from Au NPs at 532 nm in Au-PVP colloids is ascribed to surface plasmon resonance. The X-ray photoelectron spectroscopic results confirm reduction of the Au 3+ ion to Au 0 . A noticeable decrease in the binding energies of the Au4f doublet peak of the Au NP with PVP as compared to the bulk Au atom implies interfacial interaction between the Au NP and PVP molecules. A marked enhancement in vibrational band intensities of C-H (2,961, 2,936, and 2,872 cm −1 ) stretching, C-N (1,463 cm −1 ) stretching, and CH 2 (1,381 cm) bending vibrations in the pyrrolidone ring of PVP molecules reveals a charge-transfer-type interaction between the PVP molecules and surface of the Au NP. A significant decay of the emission band intensity (approximately 85%) in the π ← π* band of the PVP molecules at approximately 392 nm in the presence of Au NPs suggests non-bonding (n) electron transfer from the O atom of the pyrrolidone ring of PVP molecules to the electron-deficient Au NP. A negative zeta potential of (−) 15.2 mV reveals accumulation of n-electrons of the O atom of the carbonyl group of PVP molecules on the surface of the Au NP. Transmission electron microscopic images of PVP-capped Au NPs corroborate the spectroscopic results.

show abstract

“…Since chitosan was dissolved in aqueous acidic media, the amine groups of the D-glucosamine repeating units get protonated [1,2]. When diluted Hydroaurochloric acid was added in to chitosan solution, negatively charged gold (III) ions were adsorbed on various chains of chitosan due to electrostatic attraction with positively charged protonated amino groups [3,5]. Generally, the reduction of Au 3+ (aq) to Au 0 follows three electron transfer mechanism [6].…”

Section: Resultsmentioning

confidence: 99%

Preparation and Characterization of Gold Nanoparticles in Chitosan Suspension by One-Pot Chemical Reduction Method

Narayanan

Sivakumar

2014

View full text Add to dashboard Cite

Abstract. Gold nanoparticles were synthesized in chitosan suspension by one-pot chemical reduction method without any chemical reducing reagent. In aqueous acidic medium, chitosan exhibits polycationic nature due to protonation of amine groups of each glucosamine repeating units. The adsorption of AuCl 4-ions occurs on chitosan through electrostatic attraction and further reduction of Au 3+ to Au 0 proceeds through a three electron transfer mechanism by oxidation of protonated amine groups of chitosan chain. The change of color from dirty yellow to intense red indicates the formation of gold nanoparticles in chitosan suspension which acts as both reducing and stabilizing agent. Characterization techniques such as UV-VIS, FTIR, Zeta potential measurement, FESEM and TEM were carried out in order to examine the reduction and stabilization phenomena rendered by chitosan.

show abstract

Heavy-metal ion sensors using chitosan-capped gold nanoparticles

Cited by 298 publications

References 19 publications

Intense quenching of fluorescence intensity of poly(vinyl pyrrolidone) molecules in presence of gold nanoparticles

Intense quenching of fluorescence intensity of poly(vinyl pyrrolidone) molecules in presence of gold nanoparticles

Spectroscopy-based study on the interaction between gold nanoparticle and poly(vinylpyrrolidone) molecules in a non-hydrocolloid

Preparation and Characterization of Gold Nanoparticles in Chitosan Suspension by One-Pot Chemical Reduction Method

Contact Info

Product

Resources

About