Limits...
LED-controlled tuning of ZnO nanowires' wettability for biosensing applications.

Bhavsar K, Ross D, Prabhu R, Pollard P - Nano Rev (2015)

Bottom Line: The investigations on spectral properties of the LED emission on ZnO nanowires' wettability have shown strong dependency on the spectral overlap of LED emission on ZnO absorption spectra.The spectral investigations have provided significant insight into the role of irradiating wavelength of light and irradiation time on the surface wettability of ZnO nanowires.This process is suitable to realize on chip based integrated sensors and has huge potential for eco-friendly biosensing and environmental sensing applications.

View Article: PubMed Central - PubMed

Affiliation: IDEAS Research Institute, Robert Gordon University, Aberdeen, UK.

ABSTRACT

Background: Wettability is an important property of solid materials which can be controlled by surface energy. Dynamic control over the surface wettability is of great importance for biosensing applications. Zinc oxide (ZnO) is a biocompatible material suitable for biosensors and microfluidic devices. Nanowires of ZnO tend to show a hydrophobic nature which decelerates the adhesion or adsorption of biomolecules on the surface and, therefore, limits their application.

Methods: Surface wettability of the ZnO nanowires can be tuned using light irradiation. However, the control over wettability using light-emitting diodes (LEDs) and the role of wavelength in controlling the wettability of ZnO nanowires are unclear. This is the first report on LED-based wettability control of nanowires, and it includes investigations on tuning the desired wettability of ZnO nanowires using LEDs as a controlling tool.

Results: The investigations on spectral properties of the LED emission on ZnO nanowires' wettability have shown strong dependency on the spectral overlap of LED emission on ZnO absorption spectra. Results indicate that LEDs offer an advanced control on dynamically tuning the wettability of ZnO nanowires.

Conclusion: The spectral investigations have provided significant insight into the role of irradiating wavelength of light and irradiation time on the surface wettability of ZnO nanowires. This process is suitable to realize on chip based integrated sensors and has huge potential for eco-friendly biosensing and environmental sensing applications.

No MeSH data available.


Related in: MedlinePlus

Measured WCA change over time on ZnO nanowires irradiated with 365 nm LED. Inset pictures are captured images of water droplet on the ZnO nanowire sample, before (hydrophobic) and after (hydrophilic) the light illumination. Trend line is the exponential curve fit to the measured WCA data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4390563&req=5

Figure 0004: Measured WCA change over time on ZnO nanowires irradiated with 365 nm LED. Inset pictures are captured images of water droplet on the ZnO nanowire sample, before (hydrophobic) and after (hydrophilic) the light illumination. Trend line is the exponential curve fit to the measured WCA data.

Mentions: To see the effect of light absorption by ZnO nanowires on their surface wettability, a static WCA has been measured on the ZnO nanowire sample before and after the light irradiation using UV LED (emission wavelength, λp=365 nm). Figure 4 shows the measured WCA for the 0–30 min light illumination period, and the inset pictures show the captured images of the water droplet on the sample before (hydrophobic) and after (hydrophilic) light irradiation. Within 5 min, the ZnO nanowire surface undergoes a hydrophobic-to-hydrophilic transition. This rapid transition rate can be attributed to the nanoscale structures on the tip (13). Gradual change in WCA continues for a further 5 min, and thereafter it slows down. The reason behind this observed change in wettability by light irradiation on the ZnO nanowires can be explained as follows:


LED-controlled tuning of ZnO nanowires' wettability for biosensing applications.

Bhavsar K, Ross D, Prabhu R, Pollard P - Nano Rev (2015)

Measured WCA change over time on ZnO nanowires irradiated with 365 nm LED. Inset pictures are captured images of water droplet on the ZnO nanowire sample, before (hydrophobic) and after (hydrophilic) the light illumination. Trend line is the exponential curve fit to the measured WCA data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4390563&req=5

Figure 0004: Measured WCA change over time on ZnO nanowires irradiated with 365 nm LED. Inset pictures are captured images of water droplet on the ZnO nanowire sample, before (hydrophobic) and after (hydrophilic) the light illumination. Trend line is the exponential curve fit to the measured WCA data.
Mentions: To see the effect of light absorption by ZnO nanowires on their surface wettability, a static WCA has been measured on the ZnO nanowire sample before and after the light irradiation using UV LED (emission wavelength, λp=365 nm). Figure 4 shows the measured WCA for the 0–30 min light illumination period, and the inset pictures show the captured images of the water droplet on the sample before (hydrophobic) and after (hydrophilic) light irradiation. Within 5 min, the ZnO nanowire surface undergoes a hydrophobic-to-hydrophilic transition. This rapid transition rate can be attributed to the nanoscale structures on the tip (13). Gradual change in WCA continues for a further 5 min, and thereafter it slows down. The reason behind this observed change in wettability by light irradiation on the ZnO nanowires can be explained as follows:

Bottom Line: The investigations on spectral properties of the LED emission on ZnO nanowires' wettability have shown strong dependency on the spectral overlap of LED emission on ZnO absorption spectra.The spectral investigations have provided significant insight into the role of irradiating wavelength of light and irradiation time on the surface wettability of ZnO nanowires.This process is suitable to realize on chip based integrated sensors and has huge potential for eco-friendly biosensing and environmental sensing applications.

View Article: PubMed Central - PubMed

Affiliation: IDEAS Research Institute, Robert Gordon University, Aberdeen, UK.

ABSTRACT

Background: Wettability is an important property of solid materials which can be controlled by surface energy. Dynamic control over the surface wettability is of great importance for biosensing applications. Zinc oxide (ZnO) is a biocompatible material suitable for biosensors and microfluidic devices. Nanowires of ZnO tend to show a hydrophobic nature which decelerates the adhesion or adsorption of biomolecules on the surface and, therefore, limits their application.

Methods: Surface wettability of the ZnO nanowires can be tuned using light irradiation. However, the control over wettability using light-emitting diodes (LEDs) and the role of wavelength in controlling the wettability of ZnO nanowires are unclear. This is the first report on LED-based wettability control of nanowires, and it includes investigations on tuning the desired wettability of ZnO nanowires using LEDs as a controlling tool.

Results: The investigations on spectral properties of the LED emission on ZnO nanowires' wettability have shown strong dependency on the spectral overlap of LED emission on ZnO absorption spectra. Results indicate that LEDs offer an advanced control on dynamically tuning the wettability of ZnO nanowires.

Conclusion: The spectral investigations have provided significant insight into the role of irradiating wavelength of light and irradiation time on the surface wettability of ZnO nanowires. This process is suitable to realize on chip based integrated sensors and has huge potential for eco-friendly biosensing and environmental sensing applications.

No MeSH data available.


Related in: MedlinePlus