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Yucca-derived synthesis of gold nanomaterial and their catalytic potential.

Krishnamurthy S, Esterle A, Sharma NC, Sahi SV - Nanoscale Res Lett (2014)

Bottom Line: While low volumes of extract (0.25 and 0.5 mL) induced the formation of microscale Au sheets with edge length greater than 1 μm, high volumes yielded spherical particles ranging from 20 to 200 nm.Varying pH of the solution significantly influenced the particle shape with the production of largely spherical particles at pH 5 to 6 and truncated triangles at pH 2.Treatment with Au nanosheets and spheres demonstrated methylene blue degradation approximately 100% greater than the activity in control at 60 min.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Biology, Western Kentucky University, 1906 College Heights Boulevard, Bowling Green 42101-1080, KY, USA.

ABSTRACT
AuNPs ranging in 20 to 300 nm size were synthesized at a room temperature using Yucca filamentosa leaf extract. Diverse nanomaterial morphologies were obtained by varying the extract concentration, reaction pH, and temperature. While low volumes of extract (0.25 and 0.5 mL) induced the formation of microscale Au sheets with edge length greater than 1 μm, high volumes yielded spherical particles ranging from 20 to 200 nm. Varying pH of the solution significantly influenced the particle shape with the production of largely spherical particles at pH 5 to 6 and truncated triangles at pH 2. Separation of multidimensional nanostructures was achieved using a novel method of sucrose density gradient centrifugation. The catalytic function of Yucca-derived AuNPs was demonstrated by degradation of a wastewater dye: methylene blue using spectrophotometric measurements over time. Treatment with Au nanosheets and spheres demonstrated methylene blue degradation approximately 100% greater than the activity in control at 60 min.

No MeSH data available.


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AuNP synthesis over time. (A) TEM images showing AuNPs after (a) 6 h, (b) 12 h, (c) 24 h, and (d) 48 h. [Reaction conditions: 1 mL YFLE, 1 mM KAuCl4, pH 4.2, and 22°C to 24°C temp]. (B) UV–vis spectrometric validation of AuNPs shown in Figure 1A (a-d). The increase in the intensity of absorption peak over time correlates with the temporal increase in AuNPs synthesis.
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Figure 1: AuNP synthesis over time. (A) TEM images showing AuNPs after (a) 6 h, (b) 12 h, (c) 24 h, and (d) 48 h. [Reaction conditions: 1 mL YFLE, 1 mM KAuCl4, pH 4.2, and 22°C to 24°C temp]. (B) UV–vis spectrometric validation of AuNPs shown in Figure 1A (a-d). The increase in the intensity of absorption peak over time correlates with the temporal increase in AuNPs synthesis.

Mentions: The addition of 1 mL YFLE to 1 mM KAuCl4 (total reaction volume is 10 mL) led to the appearance of ruby red color within 3 h of incubation, indicating the formation of zero valent gold in solution. Gold nanoparticles exhibit vivid colors over time due to surface plasmon resonance phenomenon in the presence of light. Transmission electron microscopic analysis of reaction mixture revealed an increase in the population of nanoparticles with the increase in incubation time of up to 48 h (Figure 1A(a-d)). Nanomaterial shapes included spheres, triangles and cubic sheets in the size range of 10 to 500 nm. Bulk of the nanoparticles was spherical (Additional file1: Figure S1a). This synthetic pattern was also confirmed with UV–vis spectrophotometric analysis (Figure 1B) of reaction products. Absorption spectra showed a significant increase in the absorption intensity with reaction time, the peak reaching its maxima at 24 h (Figure 1B).


Yucca-derived synthesis of gold nanomaterial and their catalytic potential.

Krishnamurthy S, Esterle A, Sharma NC, Sahi SV - Nanoscale Res Lett (2014)

AuNP synthesis over time. (A) TEM images showing AuNPs after (a) 6 h, (b) 12 h, (c) 24 h, and (d) 48 h. [Reaction conditions: 1 mL YFLE, 1 mM KAuCl4, pH 4.2, and 22°C to 24°C temp]. (B) UV–vis spectrometric validation of AuNPs shown in Figure 1A (a-d). The increase in the intensity of absorption peak over time correlates with the temporal increase in AuNPs synthesis.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4256969&req=5

Figure 1: AuNP synthesis over time. (A) TEM images showing AuNPs after (a) 6 h, (b) 12 h, (c) 24 h, and (d) 48 h. [Reaction conditions: 1 mL YFLE, 1 mM KAuCl4, pH 4.2, and 22°C to 24°C temp]. (B) UV–vis spectrometric validation of AuNPs shown in Figure 1A (a-d). The increase in the intensity of absorption peak over time correlates with the temporal increase in AuNPs synthesis.
Mentions: The addition of 1 mL YFLE to 1 mM KAuCl4 (total reaction volume is 10 mL) led to the appearance of ruby red color within 3 h of incubation, indicating the formation of zero valent gold in solution. Gold nanoparticles exhibit vivid colors over time due to surface plasmon resonance phenomenon in the presence of light. Transmission electron microscopic analysis of reaction mixture revealed an increase in the population of nanoparticles with the increase in incubation time of up to 48 h (Figure 1A(a-d)). Nanomaterial shapes included spheres, triangles and cubic sheets in the size range of 10 to 500 nm. Bulk of the nanoparticles was spherical (Additional file1: Figure S1a). This synthetic pattern was also confirmed with UV–vis spectrophotometric analysis (Figure 1B) of reaction products. Absorption spectra showed a significant increase in the absorption intensity with reaction time, the peak reaching its maxima at 24 h (Figure 1B).

Bottom Line: While low volumes of extract (0.25 and 0.5 mL) induced the formation of microscale Au sheets with edge length greater than 1 μm, high volumes yielded spherical particles ranging from 20 to 200 nm.Varying pH of the solution significantly influenced the particle shape with the production of largely spherical particles at pH 5 to 6 and truncated triangles at pH 2.Treatment with Au nanosheets and spheres demonstrated methylene blue degradation approximately 100% greater than the activity in control at 60 min.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Biology, Western Kentucky University, 1906 College Heights Boulevard, Bowling Green 42101-1080, KY, USA.

ABSTRACT
AuNPs ranging in 20 to 300 nm size were synthesized at a room temperature using Yucca filamentosa leaf extract. Diverse nanomaterial morphologies were obtained by varying the extract concentration, reaction pH, and temperature. While low volumes of extract (0.25 and 0.5 mL) induced the formation of microscale Au sheets with edge length greater than 1 μm, high volumes yielded spherical particles ranging from 20 to 200 nm. Varying pH of the solution significantly influenced the particle shape with the production of largely spherical particles at pH 5 to 6 and truncated triangles at pH 2. Separation of multidimensional nanostructures was achieved using a novel method of sucrose density gradient centrifugation. The catalytic function of Yucca-derived AuNPs was demonstrated by degradation of a wastewater dye: methylene blue using spectrophotometric measurements over time. Treatment with Au nanosheets and spheres demonstrated methylene blue degradation approximately 100% greater than the activity in control at 60 min.

No MeSH data available.


Related in: MedlinePlus