Flow-through peptide synthesis and cell-based assays on Teflon-coated paper
The synthesis of peptides and proteins is an extremely complex matter, because they must be built up one amino acid at a time in repeated reaction and washing steps. Solid-phase synthesis has made this easier. Canadian researchers introduced a new variant of this technique in the journal Angewandte Chemie.
In their system, parallel syntheses take place in small regions on a paper support. The resulting peptide arrangements can be used in cell-based assays or in the search for 3D materials that support cell adhesion and growth.
In classical solid-phase synthesis, the growing peptide chain is fixed to a solid support—usually a polymer bead—so that the reagents can be rapidly and easily washed away after each step. Parallel solid-phase synthesis, known as SPOT synthesis, was developed as an alternative in the 1990s. This allows a large number of peptides to be obtained on a planar support with a small surface area.
SPOT synthesis has since been adapted for other applications, such as cell-based screening. The problem is that existing SPOT systems are not well-suited for chemical reactions. When individual drops of reagent are added by pipette, they wet small areas of the membrane—the SPOTs.
The circular spot of solvent absorbed by the membrane determines the size of the “reaction vessel”. Unlike in classical solid-phase synthesis, this limits the amounts of reagent, and flow-through conditions are not possible. This significantly limits the possible yields of the reactions.
A team headed by Frédérique Deiss and Ratmir Derda at the University of Alberta (Canada) has now found an elegant solution to this problem. The researchers used a Teflon coating to form a pattern of solvent-repellent barriers on a paper support. The pattern restricts the liquids to specific Teflon-free zones on the paper, forming small “reaction vessels” that can hold a larger volume than the usual SPOTs.
This not only allows for the use of excess volumes of reagents, but also allows for a flow-through reaction because the larger volume ensures for gravity-driven flow of the reagent solution through the paper. The flow rate can be varied by using paper of different porosity. This significantly improves yields.
There is an additional advantage to this method: the paper can be stacked or folded into thicker three-dimensional structures. The researchers were able to identify various peptides among those immobilized on the surface that support cell adhesion, growth, or differentiation in a three-dimensional environment.
About the Author
Ratmir Derda started his career as an assistant professor at the department of Chemistry at the University of Alberta in 2011. He is a principal investigator at the Alberta Glycomics Centre and Sentinel Bioactive Paper Network. In 2012, he received a Rising Star in Global Health Award from Grand Challenges Canada.
Author: Ratmir Derda, University of Alberta, Edmonton (Canada), http://derda.chem.ualberta.ca/contact/
Title: Flow-Through Synthesis on Teflon-Patterned Paper to Produce Peptide Arrays That Can Be Used for Cell-Based Assays
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201402037
Ratmir Derda | Angewandte Chemie
Fish Oil-Diet Benefits May be Mediated by Gut Microbes
28.08.2015 | University of Gothenburg
Bio-fabrication of Artificial Blood Vessels with Laser Light
28.08.2015 | Fraunhofer-Institut für Lasertechnik ILT
A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.
The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...
A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).
Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...
In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.
These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...
Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.
For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...
It comes when called, bringing care utensils with it and recording how they are used: Fraunhofer IPA is developing an intelligent care cart that provides care staff with physical and informational support in their day-to-day work. The scientists at Fraunhofer IPA have now completed a first prototype. In doing so, they are continuing in their efforts to improve working conditions in the care sector and are developing solutions designed to address the challenges of demographic change.
Technical assistance systems can improve the difficult working conditions in residential nursing homes and hospitals by helping the staff in their work and...
20.08.2015 | Event News
20.08.2015 | Event News
19.08.2015 | Event News
28.08.2015 | Physics and Astronomy
28.08.2015 | Health and Medicine
28.08.2015 | Life Sciences