Discovery of energy transfer nanostructures using gelation-driven dynamic combinatorial libraries

Abstract

Peptide self-assembly provides a useful approach to control the organization of functional molecular components, as relevant to future opto-electronic or photonic nanostructures. In this article, we report on the discovery of efficient energy transfer nanostructures using a dynamic combinatorial library (DCL) approach driven by molecular self-assembly, demonstrating an enhanced self-selection and amplification of effective energy transfer nanostructures from complex mixtures of dipeptide derivatives. By taking advantage of an enzyme-catalysed fully reversible amide formation reaction, we show how gelation shifts the equilibrium in favour of the formation of short aromatic dipeptide derivatives in the DCL system, as confirmed by reversed-phase high pressure liquid chromatography (HPLC), fluorescence emission spectroscopy, atomic force microscopy (AFM), transmission force microscopy (TEM) and circular dichroism (CD) spectroscopy. This approach enabled us to identify a two-component donor-acceptor hydrogel, which forms within minutes and exhibits efficient energy transfer

Biocatalytic Pathway Selection in Transient Tripeptide Nanostructures

“…Figure S15 shows time-dependent FTIR experiments.T EM images revealed sequential fiber formation and degradation (Figure 3c-f) with the fibers looking thinner and less twisted, similar to the fibrillar nature of 2b.It is not possible to say with certainty whether 2a and 2b form co-assembled structures or form discrete structures.T he remarkably similar degradation profile for both suggests that the degradation mechanisms are linked. However,i ti s clear from our results that 2b is preferentially formed as it is formed in ahigher yield, so in terms of molecular composition it outcompetes 2a.T hese data therefore suggest that kinetic (rather than thermodynamic) [27][28][29] selection of nanostructures occurs.A dditional TEM images for the fibrillar formation and degradation of 2a and 2b and for the competition experiments are available in Figures S16-S18. Histograms with the fibrillar length distribution for all the TEM experiments can be found in Figure S19.…”

“…[22][23][24][25][26] Thus,asystem where different peptides are formed through competing pathways provides interesting opportunities for nanostructures with adaptive functions.H erein, we demonstrate peptide-sequence-dependent kinetic pathway selection in the chemically fuelled biocatalytic self-assembly of tripeptides.W es how that these systems demonstrate transience,w ith the lifetime of the nanostructures dictated by the peptide sequence.W es tress that the approach used in this Communication is conceptually different from our previous work on equilibrium-driven enzymatic self-assembly. [27][28][29] In that work, the thermodynamic stabilization of the peptide reaction product drives the reaction and the equilibrium situation represents the assembled state,t hat is,e quilibrium-driven formation of peptide nanostructures.Inthe current approach we deliberately focus on peptides that do not assemble at equilibrium, that is,w e operate them under conditions where self-assembly is not favored. This point is key to achieving transience because,as demonstrated previously by us [20] and others, [19] nanostructure formation should be unfavorable at equilibrium.…”

Peptide π-Electron Conjugates: Organic Electronics for Biology?

“…A few of these materials have already reached application in electronic device such as in field effect transistors, while some are underway for future energy harvesting applications. [121][122][123][124] Now that the high potential of these materials have been revealed, more investigations toward the understanding of function of the self-assembled materials as well as their applications to molecular or bulk devices and biological environments are needed.…”

Peptide‐Modulated Self‐Assembly of Chromophores toward Biomimetic Light‐Harvesting Nanoarchitectonics

“…Moreover, a dansyl derivative can also be incorporated into the hydrogel of the naphthalene–FF and serve as an energy acceptor. Recently, a dynamic combinatorial library approach for discovery of such binary energy transfer hydrogels was proposed …”