Visualizing molecular weights differences in supramolecular polymers

Abstract

Issues of molecular weight determination have been central to the development of supramolecular polymer chemistry. Whereas relationships between concentration and optical features are established for well-behaved absorptive and emissive species, for most supramolecular polymeric systems no simple correlation exists between optical performance and number-average molecular weight (Mn). As such, the Mn of supramolecular polymers have to be inferred from various measurements. Herein, we report an anion-responsive supramolecular polymer [M1·Zn(OTf)2]n that exhibits monotonic changes in the fluorescence color as a function of Mn. Based on theoretical estimates, the calculated average degree of polymerization (DPcal) increases from 16.9 to 84.5 as the monomer concentration increases from 0.08 mM to 2.00 mM. Meanwhile, the fluorescent colors of M1 + Zn(OTf)2 solutions were found to pass from green to yellow and to orange, corresponding to a red shift in the maximum emission band (λmax). Therefore, a relationship between DPcal and λmax could be established. Additionally, the anion-responsive nature of the present system meant that the extent of supramolecular polymerization could be regulated by introducing anions, with the resulting change in Mn being readily monitored via changes in the fluorescent emission features.

Metal‐Ligand Interactions and Oligo(p‐phenylene vinylene) Derivatives Based Supramolecular Polymer Possessing Variable Fluorescence Colors

“…First, the complexation between M1 and Zn(OTf) 2 was clarified by quantifying the binding stoichiometry in the complexation between compound 1a ( Figure a) and Zn(OTf) 2 using the Job method. [ 39 ] The absorbance spectra corresponding to the different molar ratios of [Zn(OTf) 2 ]/([Zn(OTf) 2 ] + [1a]) are shown in Figure 2a. The original absorption peak of compound 1a in DMF/H 2 O (1/4, vol/vol) was observed at 287 nm, whose value decreased with the increasing molar ratio of [Zn(OTf) 2 ]/([Zn(OTf) 2 ] + [1a]).…”

“…Fluorescent supramolecular polymers combine the inherent advantages of supramolecular polymers in terms of dynamic nature with the optoelectronic properties of contained fluorophores. [ 33–40 ] To date, fluorescent supramolecular polymers have found their potentials in sensors, biological imaging, optoelectronic devices, etc. [ 40–44 ] However, limited by the properties of traditional fluorophores, the majority of fluorescent supramolecular polymers can only exhibit a single fluorescence color, restricting the expansion of their applications to a certain extent.…”

Removing the sporoderm from the sporoderm-broken spores of Ganoderma lucidum improves the anticancer and immune-regulatory activity of the water-soluble polysaccharide

“…By removing these polysaccharides from the cell wall of the spores, the composition of monomers was also changed. Meanwhile, the Mw of a polymer is profoundly affected by the degree of polymerization (44). The higher Mw of the polysaccharide in RSGL than in BSGL may also be due to the different degrees of polymerization of the monomers, which needs to be further examined in future studies.…”

Navigating the Expansive Landscapes of Soft Materials: A User Guide for High-Throughput Workflows

“…Other probes, such as pyrene and Reichardt’s dye, exhibit solvatochromic properties, with absorption or emission spectra dependent on the polarity of the solvent or local environment . These probes are useful for surveying both single-chain conformation , and multichain assemblies. − Fluorescent dyes, including pentameric formylthiophene acetic acid and Thioflavin T, can monitor fibrilization and β-sheet assemblies, and nucleic acid assemblies can be similarly visualized. , Dye assays also benefit from careful optimization and validation of assay conditions, including quantification of nonspecific interactions, background signal, and photobleaching, in addition to characterization with existing materials as internal calibrants.…”