| 1. |
|
|
| 2. |
- Gunnarsson, Anders, et al.
(författare)
-
Single-molecule Detection and Mismatch Discrimination of Unlabeled DNA Targets
- 2008
-
Ingår i: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 8:1, s. 183-188
-
Tidskriftsartikel (refereegranskat)abstract
- We report on a single-molecule readout scheme on total internal reflection fluorescence microscopy (TIRFM) demonstrating a detection limit in the low fM regime for short (30-mer) unlabeled DNA strands. Detection of unlabeled DNA targets is accomplished by letting them mediate the binding of suspended fluorescently labeled DNA-modified small unilamellar vesicles (Ø approximately 100 nm) to a DNA-modified substrate. On top of rapid and sensitive detection, the technique is also shown capable of extracting kinetics data from statistics of the residence time of the binding reaction in equilibrium, that is, without following neither the rate of binding upon injection nor release upon rinsing. The potential of this feature is demonstrated by discriminating a single mismatch from a fully complementary sequence. The success of the method is critically dependent on a surface modification that provides sufficiently low background. This was achieved through self-assembly of a biotinylated copolymer, Poly(L-lysine)-g-poly(ethylene glycol) (PLL-g-PEG) on a silicon dioxide surface, followed by subsequent addition of streptavidin and biotinylated DNA. The proposed detection scheme is particularly appealing due to the simplicity of the sensor, which relies on self-assembly principles and conventional TIRFM. Therefore, we foresee a great potential of the concept to serve as an important component in future multiplexed sensing schemes. This holds in particular true in cases when information about binding kinetics is valuable, such as in single nucleotide polymorphism diagnostics.
|
|
| 3. |
- Marie, Rodolphe, et al.
(författare)
-
A generic surface modification strategy for sensing applications based on Au/SiO2 nanostructures
- 2007
-
Ingår i: Biointerphases. - : American Vacuum Society. - 1934-8630 .- 1559-4106. ; 2:1, s. 49-55
-
Tidskriftsartikel (refereegranskat)abstract
- A generic protocol for the creation of material-mediated self-assembled patterns of streptavidin, defined solely by patterns of gold and SiO2, is presented. Protein-adsorption resistance of selected regions was obtained by material-specific adsorption of thiol-modified poly(ethylene)glycol (thiol-PEG) on gold followed by adsorption of poly-L-lysine (PLL) modified PEG (PLL-g-PEG) on SiO2. Selective streptavidin binding to either gold or SiO2 (or both) was ensured by introducing biotin-modified thiolated (thiol-biotin) and/or biotin-modified PLL-g-PEG (PLL-g-PEGbiotin) compounds. The introduction of biotin did not influence the protein-adsorption resistance. On the macroscopic scale, the protein-adsorption-resistant properties and the streptavidin-binding capacity were optimized using quartz crystal microbalance with dissipation monitoring. The reproduction of micrometer-scale gold patterns on SiO2 into patterns of streptavidin was verified using fluorescence microscopy, while the compatibility of the material-specific surface-modification strategy with nanoscale features was accomplished by modifying a localized surface plasmon resonance (LSPR) active template, defined by randomly distributed nanoapertures in a thin gold film on SiO2. The demonstrated compatibility of the latter substrate with LSPR-based label-free sensing of biorecognition reactions, combined with the fact that all compounds utilized are commercially available, makes the surface-modification protocol attractive as a generic surface modification solution for a broad range of biorecognition-based assays. (C) 2007 American Vacuum Society.
|
|
| 4. |
- Marie, Rodolphe, et al.
(författare)
-
Use of PLL-g-PEG in micro-fluidic devices for localizing selective and specific protein binding
- 2006
-
Ingår i: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 22:24, s. 10103-10108
-
Tidskriftsartikel (refereegranskat)abstract
- By utilizing flow-controlled PLL-g-PEG and PLL-g-PEGbiotin modification of predefined regions of a poly-(dimethylsiloxane) (PDMS) micro-fluidic device, with an intentionally chosen large (similar to 1 cm(2)) internal surface area, we report rapid (10 min), highly localized (6 x 10(-6) cm(2)), and specific surface-based protein capture from a sample volume (100 mu L) containing a low amount of protein (160 attomol in pure buffer and 400 attomol in serum). The design criteria for this surface modification were achieved using QCM-D (quartz crystal microbalance with energy dissipation monitoring) of serum protein adsorption onto PLL-g-PEG-modified oxidized PDMS. Equally good, or almost as good, results were obtained for oxidized SU-8, Topas, and poly(methyl metacrylate) (PMMA), demonstrating the generic potential of PLL-g-PEG for surface modification in various micro-fluidic applications.
|
|
| 5. |
- McGinn, Steven, et al.
(författare)
-
New Technologies for DNA analysis-A review of the READNA Project.
- 2016
-
Ingår i: New Biotechnology. - : Elsevier BV. - 1876-4347 .- 1871-6784.
-
Forskningsöversikt (refereegranskat)abstract
- The REvolutionary Approaches and Devices for Nucleic Acid analysis (READNA) project received funding from the European Commission for 4 1/2 years. The objectives of the project revolved around technological developments in nucleic acid analysis. The project partners have discovered, created and developed a huge body of insights into nucleic acid analysis, ranging from improvements and implementation of current technologies to the most promising sequencing technologies that constitute a 3(rd) and 4(th) generation of sequencing methods with nanopores and in situ sequencing, respectively.
|
|
