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Detection of formaldehyde in water: a shape-effect on the plasmonic sensing properties of the gold nanoparticles.

Nengsih S, Umar AA, Salleh MM, Oyama M - Sensors (Basel) (2012)

Bottom Line: In typical results, it was found that the plasmonic properties of gold nanostructures were very sensitive to the presence of formaldehyde in their surrounding medium by showing the change in both the plasmonic peaks position and the intensity.However, in the present study, effective plasmonic peak shift was not observed due to the intense plasmonic coupling of closely packed nanorod structures on the surface.Nevertheless, the present results at least provide a potential strategy for response enhancement via shape-effects.

View Article: PubMed Central - PubMed

Affiliation: Institute of Microengineering and Nanoelectronic (IMEN), Universiti Kebangsaan Malaysia, UKM Bangi 43600, Selangor, Malaysia. sri_nengsih85@yahoo.com

ABSTRACT
The effect of morphology on the plasmonic sensing of the presence of formaldehyde in water by gold nanostructures has been investigated. The gold nanostructures with two different morphologies, namely spherical and rod, were prepared using a seed-mediated method. In typical results, it was found that the plasmonic properties of gold nanostructures were very sensitive to the presence of formaldehyde in their surrounding medium by showing the change in both the plasmonic peaks position and the intensity. Spherical nanoparticles (GNS), for example, indicated an increase in the sensitivity when the size was increased from 25 to 35 nm and dramatically decreased when the size was further increased. An m value, the ratio between plasmonic peak shift and refractive index change, as high as 36.5 nm/RIU (refractive index unit) was obtained so far. An expanded sensing mode to FD was obtained when gold nanostructures with nanorods morphology (GNR) were used because of the presence of two plasmonic modes for response probing. However, in the present study, effective plasmonic peak shift was not observed due to the intense plasmonic coupling of closely packed nanorod structures on the surface. Nevertheless, the present results at least provide a potential strategy for response enhancement via shape-effects. High performance plasmonic sensors could be obtained if controlled arrays of nanorods can be prepared on the surface.

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Related in: MedlinePlus

Plasmonic responses of GNR upon the presence and absence of FD (10%) measured at the TSPR and LSPR peaks' wavelength.
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f8-sensors-12-10309: Plasmonic responses of GNR upon the presence and absence of FD (10%) measured at the TSPR and LSPR peaks' wavelength.

Mentions: Figure 8 shows the responses of GNR to the presence of 10% FD in water that were measured at the peak wavelength of TSPR and LSPR. As has been revealed in the figure, the GNRs exhibits an excellent sensitivity to the presence of the FD in their surroundings and recovered back to their original condition when FD was replaced by pure water. It can also be seen that the responses of the GNR measured at the LSPR peaks shows a relatively higher response than those measured at the TSPR, indicated by the decrease in the absorbance upon exposure to the FD samples. It can also be noted that despite the fact of the fluctuation in the reponses upon multiple application of FD samples to the sensor system, it can be concluded that the GNR exhibited relatively high repeatability and stability properties. One important point should be noted from these results—the use of the GNR may expand the measurement due to the presence of two measurement modes, namely TSPR and LSPR. Although relatively similar responses between the TSPR and LSPR to the current analyte system are seen, the present fact more or less has provided a potential strategy for expanding the sensing properties of the metallic nanostructures system. The response of both mode of operations might be different if the GNR system was used to detect other analyte system, such as bioorganic molecules, etc. This enables the extensive use of GNR compared to the GNS system in plasmonic sensing applications in future.


Detection of formaldehyde in water: a shape-effect on the plasmonic sensing properties of the gold nanoparticles.

Nengsih S, Umar AA, Salleh MM, Oyama M - Sensors (Basel) (2012)

Plasmonic responses of GNR upon the presence and absence of FD (10%) measured at the TSPR and LSPR peaks' wavelength.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472829&req=5

f8-sensors-12-10309: Plasmonic responses of GNR upon the presence and absence of FD (10%) measured at the TSPR and LSPR peaks' wavelength.
Mentions: Figure 8 shows the responses of GNR to the presence of 10% FD in water that were measured at the peak wavelength of TSPR and LSPR. As has been revealed in the figure, the GNRs exhibits an excellent sensitivity to the presence of the FD in their surroundings and recovered back to their original condition when FD was replaced by pure water. It can also be seen that the responses of the GNR measured at the LSPR peaks shows a relatively higher response than those measured at the TSPR, indicated by the decrease in the absorbance upon exposure to the FD samples. It can also be noted that despite the fact of the fluctuation in the reponses upon multiple application of FD samples to the sensor system, it can be concluded that the GNR exhibited relatively high repeatability and stability properties. One important point should be noted from these results—the use of the GNR may expand the measurement due to the presence of two measurement modes, namely TSPR and LSPR. Although relatively similar responses between the TSPR and LSPR to the current analyte system are seen, the present fact more or less has provided a potential strategy for expanding the sensing properties of the metallic nanostructures system. The response of both mode of operations might be different if the GNR system was used to detect other analyte system, such as bioorganic molecules, etc. This enables the extensive use of GNR compared to the GNS system in plasmonic sensing applications in future.

Bottom Line: In typical results, it was found that the plasmonic properties of gold nanostructures were very sensitive to the presence of formaldehyde in their surrounding medium by showing the change in both the plasmonic peaks position and the intensity.However, in the present study, effective plasmonic peak shift was not observed due to the intense plasmonic coupling of closely packed nanorod structures on the surface.Nevertheless, the present results at least provide a potential strategy for response enhancement via shape-effects.

View Article: PubMed Central - PubMed

Affiliation: Institute of Microengineering and Nanoelectronic (IMEN), Universiti Kebangsaan Malaysia, UKM Bangi 43600, Selangor, Malaysia. sri_nengsih85@yahoo.com

ABSTRACT
The effect of morphology on the plasmonic sensing of the presence of formaldehyde in water by gold nanostructures has been investigated. The gold nanostructures with two different morphologies, namely spherical and rod, were prepared using a seed-mediated method. In typical results, it was found that the plasmonic properties of gold nanostructures were very sensitive to the presence of formaldehyde in their surrounding medium by showing the change in both the plasmonic peaks position and the intensity. Spherical nanoparticles (GNS), for example, indicated an increase in the sensitivity when the size was increased from 25 to 35 nm and dramatically decreased when the size was further increased. An m value, the ratio between plasmonic peak shift and refractive index change, as high as 36.5 nm/RIU (refractive index unit) was obtained so far. An expanded sensing mode to FD was obtained when gold nanostructures with nanorods morphology (GNR) were used because of the presence of two plasmonic modes for response probing. However, in the present study, effective plasmonic peak shift was not observed due to the intense plasmonic coupling of closely packed nanorod structures on the surface. Nevertheless, the present results at least provide a potential strategy for response enhancement via shape-effects. High performance plasmonic sensors could be obtained if controlled arrays of nanorods can be prepared on the surface.

Show MeSH
Related in: MedlinePlus