Publications by authors named "Animesh Pan"

Article Synopsis
  • The study investigates how different pH levels affect the interaction between human serum albumin (HSA) and the ionic liquid [BMIM][OSU] at a low concentration below its critical micelle concentration (CMC).
  • Various analytical techniques, including circular dichroism (CD), nuclear magnetic resonance (NMR), and small-angle neutron scattering (SANS), reveal that the anionic part of the ionic liquid strongly binds to HSA, especially at pH 3, leading to structural changes in the protein.
  • The findings indicate that the binding interactions are primarily governed by electrostatic and hydrophobic forces, with significant implications for the behavior of proteins in ionic liquid environments across different pH levels.
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We report a multifunctional nanotherapeutic platform based on liposomes loaded with drug and iron oxide nanoparticles (IONs) coated with a gold nanoshell synthesized using a polyelectrolyte (layersome) soft templating technique. IONs and gold nanoshells were used to provide combined hyperthermia and triggered drug release via radio frequency (RF) or near-infrared (NIR) stimulation. IONs and the anticancer drug doxorubicin (DOX) were coencapsulated inside liposomes composed of zwitterionic phosphatidylcholine, anionic phosphatidylglycerol, and cholesterol lipids.

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Physicochemical studies on aqueous mixtures of ionic liquids (ILs) and reverse pluronics are limited. Self-aggregation dynamics and microstructure of a surface-active IL (SAIL), 1-butyl-3-methylimidazolium octylsulfate [Cmim] [COSO], in the presence of a reverse pluronic, POEOPO (known as 10R5), were studied using isothermal titration calorimetry (ITC), high-resolution nuclear magnetic resonance (NMR), and small-angle neutron scattering (SANS) methods. Also, cryo-/freeze-fracture transmission electron microscopy was employed to determine the microstructures of SAIL/10R5 mixtures.

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In this contribution, we have examined a composition dependent self aggregated structural modification of a catanionic mixture of the surface active ionic liquid (IL) 1-butyl-3-methylimidazolium octyl sulphate and a cationic gemini surfactant (14-5-14) in aqueous medium. We have observed that the hydrodynamic diameter of the aggregates increases with increasing IL concentration and microscopic evidence (HRTEM, FESEM, and LCSM) shows the formation of vesicle like aggregates (Dh ≈ 200 nm) at XIL = 0.5.

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Development of stable self-assembled nanostructures (especially vesicles and liposomes), and understanding their physicochemical behaviors in aqueous solution is a long-standing topic of interest in chemical and biochemical research. In this progressive area, we report for the first-time formation of mixed micelles (at pH 12), and vesicles of anionic bolaamphiphiles (dicarboxylic acids viz. [Formula: see text] , with moderate values of n 10, 11, 12, and 14) in combination with a cationic surfactant decyltrimethylammonium bromide (CTAB) in buffered aqueous medium at different pH (6.

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The "enthalpy-entropy compensation" (EEC) effect has been a long-standing fascinating yet unresolved phenomenon in chemical thermodynamics. The reasons for the observation of EEC are not clear. Various views such as empirical, extrathermodynamic, error-related, solvation, and so forth as reasons for the H/S linear correlation are floating.

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A short account of the developments and perspectives of IKR (iso-kinetic relation) and EEC (enthalpy (H) - entropy (S) compensation) has been presented. The IKR and EEC are known to be extra thermodynamic or empirical correlations though linear H-S correlation can be thermodynamically deduced. Attempt has also been made to explain the phenomena in terms of statistical thermodynamics.

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Sodium dicarboxylates (or Bola salts) with methylene spacers 0, 2, 4, 6, 8, and 10 were studied in aqueous solution to investigate their influence on the micellization of cetyltrimethylammonium bromide (CTAB). Since bolas with spacer length ≤12 are known not to micellize in general, the herein used sodium dicarboxylates were treated as 2:1 amphiphilic electrolytes which reduced surface tension of water (except sodium oxalate with zero spacer) without self-association. Their concentration dependent conductance was also linear without breaks.

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Self-aggregation of MEGA-9 (N-nonanoyl-N-methyl-D-glucamine), a nonionic sugar-based surfactant, was studied with respect to the effect of salt (NaCl) and ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) on its critical micelle concentration (cmc), aggregation number, hydrodynamic dimensions, energetics of micellization, and micellar microenvironment. Fluorimetry (both steady state and time resolved) was used to understand the microenvironments under the influence of additives. NaCl was found to decrease cmc, increase aggregation number (N), increase micellar size, and decrease enthalpy of micelle formation; the IL effect on the parameters was mostly opposite.

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The cavity in a porphyrin can accommodate metal ions through electron donor-acceptor (EDA) interaction in acetonitrile media without any specially designed fabrication with the porphyrin subunit. Alkali metal ion forms a complex with meso-tetraphenylporphyrin (TP) in 2:1 stoichiometry, while the bivalent Mg(2+) ion follows a 1:1 stoichiometry. A fluorescence interaction study indicated that TP can behave like a chemosensor for these ions present in the blood electrolytes.

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