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Nanobiotechnology 2018
Page 40
Nano Research & Applications
ISSN: 2471-9838
E u r o S c i C o n C o n f e r e n c e o n
Nanotech & Nanobiotechnology
J u l y 1 2 - 1 3 , 2 0 1 8
P a r i s , F r a n c e
D
ifferent types of click chemistry reactions have been proposed and used for the functionalization of surfaces and materials,
and covalent attachment of organic molecules. In the present work, we present and compare two different catalyst-free
click approaches, namely azide-alkyne and thiol-alkyne click chemistry, for the generation of nanobiosensors suitable for
protein detection. For this purpose, we first functionalized the surface of glass with dibenzocyclooctyne-acid (DBCO-acid), a
cyclooctyne with a carboxyl group. Then, the DBCO-terminated surfaces were functionalized with different fluorescent and
nonfluorescent azide and thiol inks via microchannel cantilevers spotting (µCP) (
Figure 1
). Click reactions were performed at
different temperatures and times and the optimum conditions of 37 °C/20 min and 37°C/40 min was found for azide-alkyne and
thiol-alkyne reactions, respectively. Although, due to no need for catalysts or additional additives, mild reaction conditions, and
high reaction rate, both routes worked reliable for surface functionalization, the protein binding experiments revealed that using a
thiol-alkyne route will obtain the highest surface density of molecular immobilization in such spotting approaches. The obtained
achievements and results from the protein binding experiments with streptavidin proved the potential for application of these
microarrays in manufacturing nanobiosensors for protein detection and other biomedical/biological applications (
Figure 2
).
Design and manufacturing of nanobiosensors suitable for
protein detection
Seyed Mohammad Mahdi Dadfar, Sylwia Sekula-Neuner, Uwe
Bog, Vanessa Trouillet and Michael Hirtz
Karlsruhe Institute of Technology (KIT), Germany
Seyed Mohammad Mahdi Dadfar et al., Nano Res Appl 2018, Volume 4
DOI: 10.21767/2471-9838-C2-011
Biography
Seyed Mohammad Mahdi Dadfar has completed his Bachelor and Master of Science at Tehran University and Shiraz University, respectively, both top-tier universities in Iran. He is
pursuing his PhD at Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology (INT) under supervision of PD Dr. Michael Hirtz and Prof. Dr. Annie Powell. His PhD project
is about functionalized diamond optomechanical circuits for infrared spectroscopy and site-specific gas sensing applications. He is a Member of Iran’s National Elites Foundation
(The highest prestige and professional nation foundation for supporting elites). Mahdi Dadfar has published more than 10 papers in reputed journals, holds two national patents
and recently has submitted another paper during his PhD.
mahdi.dadfar@kit.eduFluorescence microscope images of
microarrays of (a) azide-PEG3-biotin
conjugate immobilized on the DBCO-
terminated glass after incubating with
streptavidin-Cy3, click reaction time = 20
min, click reaction temperature = 37 ˚C;
(b) biotin-PEG-thiol immobilized on the
DBCO-terminated glass after incubating
with streptavidin-Cy3, click reaction time =
40 min, click reaction temperature = 37 ˚C.
The insets show the size distribution of the
spots. Scale bars equal 50 µm
Comparison between azide-alkyne and thiol-
alkyne click reactions: (a) bare glass; (b)
hydroxylterminated glass; (c) DBCO-terminated
glass; (d) treatment of the DBCO terminated
surface with TAMRAazide and azide-PEG3-
biotin; (e) treatment of the DBCO-terminated
surface with Cy5-PEG-thiol and biotinPEG-thiol