Hyun Kyu Park et al 2008 Nanotechnology 19 235103 doi:10.1088/0957-4484/19/23/235103
Hyun Kyu Park1,2, Anisha Gokarna3, John P Hulme4, Hyun Gyu Park2,5 and Bong Hyun Chung1,5
Show affiliationsWe describe a nanoscale strategy for detecting biotin–streptavidin binding using near-field scanning optical microscopy (NSOM) that exploits the fluorescence properties of single polydiacetylene (PDA) liposomes. NSOM is more useful to observe nanomaterials having optical properties with the help of topological information. We synthesized amine-terminated 10,12-pentacosadiynoic acid (PCDA) monomer (PCDA–NH2) and used this derivatized monomer to prepare PCDA liposomes. PCDA–NH2 liposomes were immobilized on an aldehyde-functionalized glass surface followed by photopolymerization by using a 254 nm light source. To measure the biotin–streptavidin binding, we conjugated photoactivatable biotin to immobilized PCDA–NH2 liposomes by UV irradiation (365 nm) and subsequently allowed them to interact with streptavidin. We analyzed the fluorescence using a fluorescence scanner and observed single liposomes using NSOM. The average height and NSOM signal observed in a single liposome after binding were ~31.3 to 8.5 ± 0.5 nm and 0.37 to 0.16 ± 0.6 kHz, respectively. This approach, which has the advantage of not requiring a fluorescent label, could prove highly beneficial for single molecule detection technology.
87.85.Qr Nanotechnologies-design
87.50.W- Optical/infrared radiation effects
Issue 23 (11 June 2008)
Received 25 February 2008, in final form 24 March 2008
Published 6 May 2008
Hyun Kyu Park et al 2008 Nanotechnology 19 235103
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Yuan Xing-hai et al 2009 J. Phys.: Conf. Ser. 188 012011
M O Hase and J F F Mendes 2008 J. Phys. A: Math. Theor. 41 145002
Tomonori Goto and Kazuhisa Yanagi 2009 Meas. Sci. Technol. 20 125105
J Chang et al 2008 New J. Phys. 10 103016
David Avis et al 2008 J. Phys. A: Math. Theor. 41 115301
Edisson Morgado Jr et al 2007 Nanotechnology 18 495710
Carl M Bender et al 2008 J. Phys. A: Math. Theor. 41 352003