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Trigonella foenum-graecum is an economically important plant that has significant nutraceutical properties. Various parts of the plant have previously been reported to synthesize metal nanoparticles. However, the seeds of the plant have limited potential to synthesize metal nanoparticles. Green synthesis of silver nanoparticles requires phytochemicals as reducing and metal chelating agents, in addition to the stabilizing agents that play critical role in nanoparticles stabilization. The quantitative analysis of the methanol extract of the seeds suggest that the extract has significant antioxidant activity and reducing potential which is comparable to that of ascorbic acid. Likewise, GCMS data of the extract identified several phytochemical components that have nanoparticles stabilizing potential. Evidently, the extract indeed synthesized silver nanoparticles in dark, albeit in very low quantity. This limitation of low quantity of nanoparticles synthesis was overcome by photocatalysis. The rate of nanoparticles synthesis increased significantly with increase in the intensity of the white light-emitting diode (LED) light. Furthermore, the photocatalytic effect of the white light also has significant impact on the physicochemical characterisation of the nanoparticles. Particle size, nanoparticles yield and elemental analysis demonstrated that the 2000 lumens white LED light is optimum for photocatalysis as compared to the 250 lumens and 825 lumens light. However, the stability of nanoparticles is not influenced by photoirradiation, and is rather controlled by the phytochemical composition of the extract. Methanol extract of the seeds significantly enhanced the stability of the silver nanoparticles irrespective of the light intensities used for photocatalysis.

Recently, there has been growing interest in the hierarchical assemblies of zwitterionic betaine amphiphiles across various fields due to their utility as stimuli-responsive materials. Herein, we systematically investigate the binary supramolecular assembly of zwitterionic amido betaines and diamines to determine how alkyl chain length of amido betaines (C_nDAB) and amine degree of diamines influence their relaxation dynamics of the resultant coacervates. To this end, we synthesized five C_nDAB molecules with systematically varying carbon chain lengths (n = 12, 14, 16, 18, and 20) and conjugated them with three different diamines (ethylenediamine, EDA; n,n'-dimethylethylenediamine, DMEDA; and n,n,n',n'-tetramethylethylenediamine,TMEDA). We employed rheology to compare the bulk properties and relaxation dynamics of these assemblies as well as to gain insight into their responsiveness to pH stimulus. All betaine/diamine co-assemblies for all pH values showed shear-thinning behavior while the onset of shear thinning behavior showed some variation for the shear rate inducing such an onset. By changing molecular architecture of co-assembling pairs, zero-shear viscosity values varied from ∼10⁻¹ Pa s to ∼10³ Pa s at a concentration of 100 mM C_nDAB and 50 mM diamine in water. Four-order-of-magnitude difference in viscosity with small changes in molecular architecture and pH indicates that precise tuning of the rheological properties is possible simply by controlling the self-assembly tendencies and nano-to-micro scale aggregation morphologies through bi-molecular design. Out of 15 different combinations of betaine and diamine pairs studied, the primary amine EDA conjugated with C₁₈DAB resulted in the highest degree of pH-controlled viscosity changes (i.e., highest pH-responsivity). Below 16-carbon alkyl chains on the betaines, pH responsiveness mostly disappeared. Overall, this systematic study brings new insights into the molecular structure-property relationships of amido betaine/diamine systems, which are widely used in diverse sets of applications and fields.

The review discusses the development of a quantum chemical approach for calculating the thermodynamic clusterization parameters of surfactants at the air/water interface. It characterizes the intermolecular interactions that govern the process of surfactant association. Of particular interest are the dispersion interactions CH···HC between the hydrophobic chains of surfactants, as well as their accurate description within the exploited scheme and semiempirical methods. The scheme is based on calculating the thermodynamic parameters of formation for a certain number of surfactant monomers and small clusters with different chain lengths using the supermolecule approximation. Furthermore, it enables the construction of an additive scheme with assessed values of the increments of CH···HC interactions and interactions between the hydrophilic parts. This scheme provides equations for thermodynamic clusterization parameters per one surfactant molecule of infinite 2D films. The number of parameters adequately assessed within this approach is described in the previous review in Colloid Polym. Sci., 2015, 293, 3065–3089: the threshold chain length of spontaneous clusterization, the “temperature effect” of clusterization, and the assessment of the molecular tilt angle of the surfactant with respect to the interface. In this context, our aim is to describe additional parameters and experimental phenomena. These include the dependence of the area per surfactant molecule in a 2D monolayer at the LE-LC phase transition on temperature and chain length, the correlation of the surfactant clusterization threshold with the solubility threshold, and with the donor-acceptor properties of the substituents included in the hydrophilic part. We also explore surfactant binary mixtures, surfactant – alkane mixtures, and the role of amphiphiles in the formation of alkane adsorption layers. Additionally, we investigate the shifting of the acid or base value (pK_a, pK_b) of surfactants with chain elongation during monolayer formation, as well as the dendricity of surfactant domains with an increase in temperature or shortening of chain length.

Bifonazole (BF), belonging to the newer class of antifungal drugs, is being widely explored for topical administration for fungal infections. It has proven to have better efficiency than other older drugs. However, it's low solubility poses a challenge in the formulation and, therefore, in the drug product's efficacy. Intending to harness the benefits of the drug, the objective of the current study was to prepare a supersaturated system of the drug with a coformer. A co-amorphous system (CAS) of BF and citric acid (CA) was prepared using solvent evaporation to achieve better permeation and antimicrobial efficacy after topical application. The prepared system was evaluated for its solid-state properties by DSC, XRD, and FTIR. The theoretical values of the glass transition temperature, as calculated by the Gordon-Taylor equation, correlated well with the observations of the thermal analysis. The prepared system was dispersed in propylene glycol to perform in-vitro permeation studies wherein enhanced permeation properties were noted. The CAS showed better antifungal properties against A. niger owing to better release and solubility of the drug. Thus, It was concluded that a co-amorphous system of BF is a promising formulation strategy for topical drug delivery.

In the current research, acyclovir-loaded microbeads were formulated via ionotropic gelation using sodium alginate-gellan gum and sodium alginate-xanthan gum. In the preparation of these acyclovir-loaded microbeads, aluminium chloride and barium chloride were used as cross-linking agents. All these ionotropically-gelled acyclovir-loaded alginate-gellan gum microbeads and alginate-xanthan gum microbeads exhibited good percent yields (85.07 ± 1.58 to 92.17 ± 3.02%) and drug entrapment efficiencies (74.09 ± 1.38 to 95.16 ± 3.37%). Acyclovir-loaded alginate-gellan gum microbeads exhibited comparatively smaller average particle sizes (0.54 ± 0.02 to 0.71 ± 0.03 mm) than those of acyclovir-loaded alginate-xanthan gum microbeads (0.60 ± 0.02 to 0.82 ± 0.04 mm). Acyclovir-loaded alginate-xanthan gum microbeads exhibited comparatively higher swelling than that of acyclovir-loaded alginate-gellan gum microbeads. A sustained pattern of acyclovir release over 240 min was noticed by these microbeads. Surface morphology analysis of the best microbeads formulation (on the basis of sustained acyclovir release data) was done by scanning electron microscopy (SEM). These kinds of ionotropically-gelled alginate-based microbeads might be advantageous to facilitate enhanced patient compliances with minimal dosing frequency and enhanced oral bioavailability.

A new mathematical solution to the non-linear Poisson-Boltzmann differential equation for solid-liquid dispersions in presence of different dissymmetrical electrolytes was given. The analytical expressions of the surface and charge density of solid particles were given. The variations of electrostatic potential ψ (x) and charge density σ (x) of dispersed particles against the distance x were obtained. For colloidal particles in presence of E(m-n) electrolytes with $m\ne n$ with $m\ge 3,n\ge 3$ and for E(2–3) and E(3-2) electrolytes, the mean electrostatic potential as a function of the distance was numerically integrated by Mathematica program version 13.

The experimental study of silica suspensions in presence with the following electrolytes $NaCl$, ${Na}_2{SO}_4$, $Ca{Cl}_2$, ${Na}_3{PO}_4$, $Al{Cl}_3$, ${Al}_2{\left({SO}_4\right)}_3$, ${Ca}_3{\left({PO}_4\right)}_2$, ${Na}_4{P_{2}O}_7$ and ${Na}_5{P_{3}O}_{10}$ led to confirm the theoretical predictions obtained from the analytical solution of Poisson-Boltzmann equation. The results obtained allowed to determine the surface potential as a function of pH of the suspension and the electrostatic potential versus the distance x. The variations of the dissociation coefficient of silica surfaces were determined. An important effect of the anion and cation valences of the dissymmetrical electrolytes on the surface charge density and potential was highlighted.

Tocopherols are fat soluble substances with antioxidant properties. The α-Tocopherol (T) is the major form of Tocopherols and can decrease the risk of cancer. F127-based and Lignin-based oil-in-water microemulsions seem to increase the bioavailability of T and cause better release of this therapeutic agent. Thus, T-loaded microemulsions were designed by means of density functional theory (DFT) and semi-empirical methods. Atoms in molecules (AIM), natural bond orbital (NBO) analyses, localized molecular orbital energy decomposition analysis (LMO-EDA), and density of states plots were employed to explore the effective factors on the strength of the interactions between surfactants and T. Results indicate that F127-T complexes are more stable than Lignin-T ones. Furthermore, the stable release of T in microemulsions is due to the electrostatic interactions between surfactants and T. Formation of hydrogen bond (HB) interactions between surfactants and T stabilizes the microemulsion system. These interplays are suggested to take part in the better function of T in microemulsions compared to free T. The semi-empirical study reveals that the heats of formation (ΔH_f values) of the F127-T complexes are less negative than those for the Lignin-T ones.