Assembly of naphthalenediimide conjugated peptides: aggregation induced changes in fluorescence

Abstract

Naphthalenediimide appended peptide based self-assembly was studied. Interestingly, an aggregation induced drastic change in the fluorescence property and gel formation were observed depending on the solvent composition (chloroform : methylcyclohexane) at a fixed concentration of 1.6 mM at room temperature.

Charge‐Transfer Complex Formation in Gelation: The Role of Solvent Molecules with Different Electron‐Donating Capacities

“…An instant colour www.chemeurj.org change was also observed for the formation of this type of complex. The solution of the NDI-containing gelator in chloroform shows a very feeble fluorescence; [8] however, a mixture of 1 (3 mm) in chloroform and toluene shows a significant fluorescence band at 495 nm (Figure 4 b). This observation is supported by the unchanged UV spectrum with respect to time.…”

“…Such types of CT complex formation leads to a visible colour change during complex formation. In the course of our exploration of the self-assembly of NDIbased compounds, [8] we have encountered an interesting finding of the formation of a CT complex based gel of an NDI-containing peptide in chloroform/aromatic hydrocarbon based solvent(s), including toluene, xylenes and mesitylene. NDI is a brilliant n-type semiconducting molecule with appealing properties, including molecu-lar planarity, electron acceptability and characteristic redox behaviour.…”

Self-Assembly of Peptide Bioconjugates: Selected Recent Research Highlights

“…In one recent impressive example, Banerjee's group has developed gelators based on a naphthalene diimide core with symmetrically attached alkylated peptides, and showed that the fluorescence properties change upon formation of J-aggregate structures. 66 In another development, they discovered a two-component peptide-based system exhibiting white light emission. 67 This was observed for mixtures of 1 and 2 (Fig.4) where 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 It has recently been shown that conjugation of the fluorophore FITC [fluorescein isothiocyanate] to the simple dipeptide dileucine produces a cyto-compatible conjugate that is taken up by dermal or corneal fibroblasts in contrast to FITC itself.…”

Controlled self-assembly of small molecule probes and the related applications in bioanalysis

“…The nanoparticles exhibit enhanced green excimer fluorescence. Basak et al (2013) studied the self-assembly of two naphthalene diimide based peptide gelators in various organic solvents. The gelator itself exhibits very weak fluorescence in solution state, and it emits bright yellow color in the aggregated gel state.…”