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
Breaking through a double wall with a sledgehammer
29.06.2015 | Max-Planck-Institut für Entwicklungsbiologie
Lean but sated: Molecular Switch for a Healthy Metabolism discovered
29.06.2015 | Leibniz-Institut für Altersforschung - Fritz-Lipmann-Institut e.V. (FLI)
Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and a half billion years ago.
Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and...
A team of scientists including PhD student Friedrich Schuler from the Laboratory of MEMS Applications at the Department of Microsystems Engineering (IMTEK) of...
The three-year clinical trial results of the retinal implant popularly known as the "bionic eye," have proven the long-term efficacy, safety and reliability of...
On June 23, the second Sentinel mission was launched from the space mission launch center in Kourou. A critical component of Aachen is on board. Researchers at the Fraunhofer Institute for Laser Technology ILT and Tesat-Spacecom have jointly developed the know-how for space-qualified laser components. For the Sentinel mission the diode laser pump module of the Laser Communication Terminal LCT was planned and constructed in Aachen in cooperation with the manufacturer of the LCT, Tesat-Spacecom, and the Ferdinand Braun Institute.
After eight years of preparation, in the early morning of June 23 the time had come: in Kourou in French Guiana, the European Space Agency launched the...
(Nano)islands that slide freely on a sea of copper, but when they become too large (and too dense) they end up getting stuck: that nicely sums up the system...
25.06.2015 | Event News
16.06.2015 | Event News
11.06.2015 | Event News
29.06.2015 | Life Sciences
29.06.2015 | Life Sciences
29.06.2015 | Physics and Astronomy