Probing the Gelatin–Alkylammonium Salt Mixed Assemblies through Surface Tensiometry and Fluorimetry

Abstract

The interactions, nature of the organization, and physicochemical properties of alkyltrimethylammonium bromide (C TAB, n = 12, 14, and 16)-gelatin mixed assemblies were investigated by UV-visible spectrometry, surface tensiometry, and fluorimetry techniques. The synergistic interaction between the surfactant and gelatin was established from the decrease in critical micellar concentration (cmc) and the increase in molecular parking area of surfactants with an increase in percentage of gelatin from 0 to 0.4%; for example, the cmc of CTAB decreased from 0.93 mM in water to 0.44 mM in the presence of 0.4% gelatin, whereas its A increased from 134.98 to 325.55 Å. The fluorescence anisotropy data and polarity parameters of pyrene indicated the progressive change in the anisotropy and micropolarity of the mixed system media with gelatin percentage, respectively. The decrease in aggregation number with an increase in gelatin concentration can be attributed to the enhanced compatibility of surfactants with the bulk microenvironment. The maximum rigidity of the mixed system was also significant from the lifetime data of tyrosine. The formation of Menger micelles on gelatin segments was supported by surface tension and anisotropy data. The overall observations can be attributed to the formation of micelles via gelatin-surfactant aggregates; gelatin segments are localized within the microdomain of these aggregates.

Developing centrifugal spun thermally cross‐linked gelatin based fibrous biomats for antibacterial wound dressing applications

“…As seen in Figure 1, in the case of the neat gelatin solution, there was an intense and sharp peak at about 300 nm, corresponding to peptide bonds in the gelatin. [ 45, 46 ] In the case of Ag‐G20, that peak shifted to around 330 nm. Ag‐G20 also exhibited a wider peak centered at about 405 nm, indicating formation of the Ag NPs in the solution.…”

Isolation, process optimisation and characterisation of the protein from the de‐oiled cake flour of Madhuca latifolia

“…On the other hand, the protein can assume charged or neutral character depending on the pH of its immediate environment and its isoelectric point. For most of the proteins, the isoelectric point lies within 4.8–5.0 [39, 40]. To ascertain the solubilisation site and nature of orientation of the protein present in MDF within an RM, the point of zero charge (PZC) and natural pH of MDF in water were determined (Fig.…”

“…This leads to the separation of RMP from the other biomolecules in MDF. Within the water pool, RMP arranges itself to get minimal free‐energy constraints [39, 40, 43]. Consequently, the driving forces for the solubilisation of RMP within the water pool are: (i) the electrostatic attraction between the hydrophilic surfactant (headgroups) of AOT and charged regions of the protein; and (ii) the hydrophobic interactions among the nonpolar segments of the protein.…”

“…In principle, the yield of RMP obtained from the water pool is supposed to increase because of the electrostatic repulsion between the polar head groups of the surfactant and the carboxylate ions of RMP as the pH increases. At a high pH, the percentage of protonated amine decreases, and RMP is denatured (unfolded) beyond the optimal pH of the solution up to which the protein retains its identity, thus exposing its hydrophobic segments to the water medium [39, 40]. Moreover, the association of protein molecules with the surfactant hydrocarbon chains and bulk nonpolar medium occurs via hydrophobic interactions.…”

In vitrocoronal protein signatures and biological impact of silver nanoparticles synthesized with different natural polymers as capping agents

“…Absorption maximum of alginate in water is at ~210 nm 74. Gelatin has two absorption maxima, one corresponds to the presence of peptide bond and side chains of the aromatic groups (π → π* transition) at 220 nm, and the other corresponds to the aromatic side chains (n → π* transition) at 280 nm 75. The absorption maximum of (unmodified) silk fibroin polymer is at 280 nm 76.…”