Investigation of the impacts of simple electrolytes and hydrotrope on the interaction of ceftriaxone sodium with cetylpyridinium chloride at numerous study temperatures.

Herein, interactions between cetylpyridinium chloride (CPC) and ceftriaxone sodium (CTS) were investigated applying conductivity technique. Impacts of the nature of additives (e.g. electrolytes or hydrotrope (HDT)), change of temperatures (from 298.15 to 323.15 K), and concentration variation of CTS/additives were assessed on the micellization of CPC + CTS mixture. The conductometric analysis of critical micelle concentration (CMC) with respect to the concentration reveals that the CMC values were increased with the increase in CTS concentration. In terms of using different mediums, CMC did not differ much with the increase in electrolyte salt (NaCl, Na2SO4) concentration, but increased significantly with the rise of HDT (NaBenz) amount. In the presence of electrolyte, CMC showed a gentle increment with temperature, while the HDT showed the opposite trend. Obtained result was further correlated with conventional thermodynamic relationship, where standard Gibb's free energy change (ΔGmo), change of enthalpy (ΔHmo), and change of entropy (ΔSmo) were utilized to investigate. The ΔGmo values were negative for all the mixed systems studied indicating that the micellization process was spontaneous. Finally, the stability of micellization was studied by estimating the intrinsic enthalpy gain (ΔHmo,∗) and compensation temperature (Tc). Here, CPC + CTS mixed system showed more stability in Na2SO4 medium than the NaCl, while in NaBenz exhibited the lowest stability.

Signal Transducer and Activator of Transcription 6 Changes and Protein Frustration by Single Amino Acid Substitutions: Implications for Cancer Progression.

Signal transducer and activator of transcription 6 (STAT6) is a multifunctional protein that plays critical functions in cell proliferation, apoptosis, differentiation, and angiogenesis. Mutations in STAT6 may contribute to the development of certain complex diseases such as cancer. This study examined single amino acid substitutions in STAT6 to pinpoint deleterious variants and their related structural and functional impairments. Data on STAT6 mutations were obtained from the Ensembl database and analyzed to evaluate the selected mutations for their pathogenicity and destabilizing or harmful effects. Specifically, we analyzed aggregation propensity, nonpacking density, and accessible surface area on the chosen mutations. The results suggest that seven out of eight mutations are less soluble, which might lead to aggregation, disrupt ordered helices, and alter strand propensity. Four mutations lay in the conserved regions of the protein, as revealed by the Consurf analysis. We found that three mutations, E318G, L365F, and R562H, change hydrophobic contacts and lead to frustration of STAT6, which can alter its stability, contributing to disease progression in cancer. In conclusion, these findings inform how single amino acid changes can destabilize STAT6. This has implications for cancer progression which warrants further experimental research.

Polymer Membranes of Zeolitic Imidazole Framework-8 with Sodium Alginate Synthesized from ZIF-8 and Their Application in Light Gas Separation.

The potential of nanocomposite membranes (NCMs) prepared by the sodium alginate polymer and embedded with synthesized zeolitic imidazole framework-8 (ZIF-8) as fillers having microporous structure in the application of separation of gaseous mixture generated by the process of methane reforming was assessed. ZIF-8 crystals were created through hydrothermal synthesis, with sizes varying from 50 to 70 nm. NCMs were prepared with a 15% filler loading, i.e., synthesized ZIF-8. NCMs (ZIF-8) having H2 permeability of 28 Barrer and H2/CH4 selectivity of 125 outperformed neat polymer membranes in terms of separation performance at ambient temperature and 4 kg/cm2 pressure. The purity of H2 increased to as high as 95% among the measured values. The NCMs did not, however, outperform a neat polymer membrane in terms of their ability to separate mixtures of gases. Moreover, the combination of ZIF-8 as a filler with sodium alginate was new and had not been reported previously. As a result, it is worthwhile to investigate.

Green Composites Based on Animal Fiber and Their Applications for a Sustainable Future.

Global climate change is already affecting the environment, as glaciers are receding, ice on rivers and lakes is melting, plant and animal range`s have altering, and trees are blooming early. Therefore, focus has shifted towards sustainable materials. There is a growing desire for materials that have a unique combination of qualities that metals, polymers, and other materials cannot provide, therefore scientists are turning their focus to green composites. Green composites offer a wide range of uses in automotive, aerospace, and marine applications. Composites are multiphase resources with separate interfaces that contain chemically different materials. Composites are made up of a variety of materials that are distinct in nature, and they give a set of desirable features that are superior to those of their predecessors or parents. Natural fibers are less expensive, more readily available, rust-resistant, plentiful, nontoxic, and safe for human skin, eyes, and respiratory systems. Green composites are created by combining renewable fibers with polymers (matrix) to create a new class of composites known as "green composites." This review includes studies on various animal-based fibers and their applications. In this article, recent advancements in the field of these fibers and their composites of fibers are also discussed. The physical, chemical, and mechanical properties are also discussed in this paper. Moreover, the benefits and drawbacks of using these fibers are also discussed in detail. Finally, the paper gives an outline of the topic. The results from composites constructed from each fiber are provided, along with appropriate references for more in-depth analysis studies. This review is specially performed to strengthen the knowledge bank of the young researchers working in the field of natural composites.

Identifying bioactive phytoconstituents as C-terminal Src kinase inhibitors: a virtual screening and molecular simulation approach.

Tyrosine-protein kinase CSK otherwise known as C-terminal Src kinase (CSK), is involved in multiple pathways and processes, including regulating cell growth, differentiation, migration, and immune responses. Altered expression of CSK has been associated with various complexities, including cancer, CD45 deficiency, Osteopetrosis and lupus erythematosus. Important auxiliary roles of CSK in cancer progression make it a crucial target in developing novel anticancer therapy. Thus, CSK inhibitors are of concern as potent immuno-oncology agents. In this perspective, phytochemicals can be a significant source for unraveling novel CSK inhibitors. In this study, we carried out a systematic structure-based virtual screening of bioactive phytoconstituents against CSK to identify its potential inhibitors. After a multi-step screening process, two hits (Shinpterocarpin and Justicidin B) were selected based on their druglike properties and binding affinity towards CSK. The selected hits were further analyzed for their stability and interaction via all-atom molecular dynamics (MD) simulations. The selected hits indicated their potential as selective binding partners of CSK, which can further be used for therapeutic development against CSK-associated malignancies.Communicated by Ramaswamy H. Sarma.

Influence of twin-headed gemini micellar system on the study of methionine amino acid with ninhydrin in buffer solution.

The influence of double-headed gemini was examined in the present study by studying the amino acid methionine mixed with ninhydrin in CH3COOH-CH3COONa buffer solvent. The absorbance was monitored at fixed time intervals with UV-vis spectroscopy. An impact typical of surfactants was observed on the ninhydrin-methionine reaction and explained by a pseudo-phase model of micelles. The effect of different temperatures (343 to 363 K) was also determined. Based on data showing the impact of temperature on kψ , several relevant thermodynamic quantities, ΔH #, ΔS #, and E a, were calculated using linear least-squares regression. In addition, the influence of the other reaction ingredients on the reaction, that is, pH and the concentration of ninhydrin and methionine, was studied. The CMC (critical micelle concentration) of pure geminis and the surfactant system with methionine and ninhydrin was evaluated at two temperatures, i.e. at 303 K and 353 K by conductivity measurements. The CMC values of pure gemini surfactants evaluated in the existing case at 303 K are concordant with the results stated before. Moreover, other parameters, including rates and binding constants, were calculated.

Physico-chemical properties of the association of cetyltrimethylammonium bromide and bovine serum albumin mixture in aqueous-organic mixed solvents.

Herein, we have investigated the association behavior of bovine serum albumin (BSA) and cetyltrimethylammonium bromide (CTAB) using the conductivity method in H2O and H2O + organic mixed solvents at different temperatures. The association phenomenon was detected from the deviation of the conductivity changes with enhancing the surfactant concentration and changes of numerous physico-chemical properties, such as CMC, α, ß and thermodynamic variables (∆G0m, ∆H0m and ∆S0m). The values of CMC for the CTAB + BSA system in 10 % (v/v) solvents follow the trend: CMCwater < CMCwater+DMSO < CMCwater+AN < CMCwater+DX < CMCwater+DMF. The interaction of BSA with CTAB is notably influenced due to a change of temperature and extent of hydration of BSA and surfactant. The obtained values of -∆G0m manifest that the association of BSA and CTAB mixture is a spontaneous process, while the values of -∆G0m in presence of 10 % (v/v) aq. organic solvents come out in the given sequence: -∆Gmo (H2O + DMSO) > ∆Gmo (H2O + DMF) > -∆Gmo (H2O + DX) > -∆Gmo (H2O + AN). The H-bonding, ion-dipole, along with the hydrophobic interactions, are believed to be the binding interactions between BSA and CTAB in the study media.

Synergistic Interaction and Binding Efficiency of Tetracaine Hydrochloride (Anesthetic Drug) with Anionic Surfactants in the Presence of NaCl Solution Using Surface Tension and UV-Visible Spectroscopic Methods.

Surfactants are ubiquitous materials that are used in diverse formulations of various products. For instance, they improve the formulation of gel by improving its wetting and rheological properties. Here, we describe the effects of anionic surfactants on an anesthetic drug, tetracaine hydrochloride (TCH), in NaCl solution with tensiometry and UV-visible techniques. Various micellar, interfacial, and thermodynamic parameters were estimated. The outputs were examined by using different theoretical models to attain a profound knowledge of drug-surfactant mixtures. The presence of attractive interactions among drug and surfactant monomers (synergism) in mixed micelle was inferred. However, it was found that sodium dodecyl sulfate (SDS) showed greater interactions with the drug in comparison to sodium lauryl sarcosine (SLS). The binding of the drug with surfactants was monitored with a spectroscopic technique (UV-visible spectra). The results of this study could help optimize the compositions of these mixed aggregates and find the synergism between monomers of different used amphiphiles.

Biomedical features and therapeutic potential of rosmarinic acid.

For decades, the use of secondary metabolites of various herbs has been an attractive strategy in combating human diseases. Rosmarinic acid (RA) is a bioactive phenolic compound commonly found in plants of Lamiaceae and Boraginaceae families. RA is biosynthesized using amino acids tyrosine and phenylalanine via enzyme-catalyzed reactions. However, the chemical synthesis of RA involves an esterification reaction between caffeic acid and 3,4-dihydroxy phenyl lactic acid contributing two phenolic rings to the structure of RA. Several studies have ascertained multiple therapeutic benefits of RA in various diseases, including cancer, diabetes, inflammatory disorders, neurodegenerative disorders, and liver diseases. Many previous scientific papers indicate that RA can be used as an anti-plasmodic, anti-viral and anti-bacterial drug. In addition, due to its high anti-oxidant capacity, this natural polyphenol has recently gained attention for its possible application as a nutraceutical compound in the food industry. Here we provide state-of-the-art, flexible therapeutic potential and biomedical features of RA, its implications and multiple uses. Along with various valuable applications in safeguarding human health, this review further summarizes the therapeutic advantages of RA in various human diseases, including cancer, diabetes, neurodegenerative diseases. Furthermore, the challenges associated with the clinical applicability of RA have also been discussed.

Interaction of TX-100 and Antidepressant Imipramine Hydrochloride Drug Mixture: Surface Tension, 1H NMR, and FT-IR Investigation.

Interfacial interaction amongst the antidepressant drug-imipramine hydrochloride (IMP) and pharmaceutical excipient (triton X-100 (TX-100-nonionic surfactant)) mixed system of five various ratios in dissimilar media (H2O/50 mmol·kg-1 NaCl/250 mmol·kg-1 urea) was investigated through the surface tension method. In addition, in the aqueous solution, the 1H-NMR, as well as FT-IR studies of the studied pure and mixed system were also explored and deliberated thoroughly. In NaCl media, properties of pure/mixed interfacial surfaces enhanced as compared with the aqueous system, and consequently the synergism/attractive interaction among constituents (IMP and TX-100) grew, whereas in urea (U) media a reverse effect was detected. Surface excess concentration (Γmax), composition of surfactant at mixed monolayer (X1σ), activity coefficient (f1σ (TX-100) and f2σ (IMP)), etc. were determined and discussed thoroughly. At mixed interfacial surfaces interaction, parameter (ßσ) reveals the attractive/synergism among the components. The Gibbs energy of adsorption (ΔGadso) value attained was negative throughout all employed media viewing the spontaneity of the adsorption process. The 1H NMR spectroscopy was also employed to examine the molecular interaction of IMP and TX-100 in an aqueous system. FT-IR method as well illustrated the interaction amongst the component. The findings of the current study proposed that TX-100 surfactant could act as an efficient drug delivery vehicle for an antidepressant drug. Gels can be used as drug dosage forms due to recent improvements in the design of surfactant systems. Release mechanism of drugs from surfactant/polymer gels is dependent upon the microstructures of the gels and the state of the drugs within the system.

Mixed Micellization, Thermodynamic and Adsorption Behavior of Tetracaine Hydrochloride in the Presence of Cationic Gemini/Conventional Surfactants.

In this approach, tensiometry and UV-visible techniques are used to determine the effect of cationic gemini and conventional surfactants on tetracaine hydrochloride (TCH), an anesthetic drug. We have estimated micellar, interfacial, and energetic constraints. To gain a deep understanding of their mixed association behavior, the outputs were examined using different theoretical models. The critical micelle concentration for single and mixed amphiphiles was estimated. The cmc values of mixed amphiphiles were found between the individual amphiphiles due to strong attractive interaction (synergism) between the components after mixing. The non-ideal behavior of mixtures was confirmed by the larger values of ideal cmc than the experimental cmc values. The negative values of interaction parameter (ß) and values of activity coefficients less than unity indicate strong synergistic interaction between drug and surfactant. The stability of the mixed systems is demonstrated by the negative Gibbs free energy of micellization and excess free energy of micellization. In contrast to a single chain surfactant, a double chain surfactant (gemini) exhibits better interactions with the drug. Spectral measurements (UV-visible spectra) were used to monitor the binding of the drug with surfactant (conventional as well as gemini). Studying these mixed aggregates could help to optimize their compositions and find synergistic properties between TCH monomers and surfactants.

Effects of various media on micellization, adsorption and thermodynamic behaviour of imipramine hydrochloride and antimicrobial surfactant mixtures.

The effect of various media (aqueous, NaCl, urea (U) and thiourea (TU)) on the micellization and adsorption activity of varied mixtures of imipramine hydrochloride (IMP) and benzethonium chloride (BZCl) is investigated via tensiometry. In an aqueous medium, the interactions between IMP and BZCl are also evaluated using UV-visible and FTIR spectroscopy. The interaction between components increases with increased mole fraction (α 1) of BZCl in the mixed system (IMP + BZCl). Different parameters, such as micellar and the mixed monolayer component composition, the interaction parameters of the solution and the interface, the activity coefficients of the components in solution and at the interface, and thermodynamic parameters, are computed using different proposed theoretical models (i.e. Clint, Motomura, Rubingh and Rosen). The cmc values obtained for the pure components and mixtures (IMP + BZCl) of all the compositions are found to be less in NaCl than in the aqueous solution while found more in the presence of U or TU. TU is more effective in increasing the cmc of the pure and mixed systems than U. The Gibbs free energy ( Δ G mic ∘ ) values of the studied pure and mixed systems are negative, showing the spontaneous nature of the reaction.

Investigation of Solution Behavior of Antidepressant Imipramine Hydrochloride Drug and Non-Ionic Surfactant Mixture: Experimental and Theoretical Study.

In this paper, the interaction of imipramine hydrochloride (IMP, antidepressant drug) and a non-ionic surfactant Triton X-100 (TX-100) mixture in five different ratios through the tensiometric method in different solvents (aqueous/0.050 mol·kg-1 aqueous NaCl/0.250 mol·kg-1 aqueous urea (U)) were examined thoroughly at a temperature of 298 K. UV-Visible studies in an aqueous system of IMP + TX-100 mixtures were also investigated and discussed in detail. The pure (IMP and TX-100) along with the mixtures' critical micelle concentration (cmc) were assessed by a tensiometric technique. The obtained deviation of the mixtures' cmc values from their ideal values revealed the nonideal behavior of IMP + TX-100 mixtures amongst IMP and TX-100. Compared to aqueous systems, in the presence of aqueous NaCl, several changes in micelles/mixed micelles occurred, and hence a synergism/attractive interaction amongst components was found increased while in the existence of U, the synergism/attractive interaction between them decreased. The evaluated interaction parameter (ßRb) value of mixed micelles showed the attractive or synergism between the IMP and TX-100. Various evaluated thermodynamic parameters in an aqueous system showed that the mixed micellization of the IMP + TX-100 mixture was an entropically spontaneous phenomenon, although the existence of salt in all studied systems can somewhat increase the spontaneity of the micellization process and in the aqueous U system, the spontaneity of the micellization process decreased. In an aqueous system, the interaction between IMP and TX-100 was also confirmed by UV-Visible study.

Mixed Micellization and Spectroscopic Studies of Anti-Allergic Drug and Non-Ionic Surfactant in the Presence of Ionic Liquid.

In drug delivery, surfactants are used to reduce side effects and to increase drug efficiency. The present work aimed to study the interaction of diphenhydramine hydrochloride (anti-allergic drug) with TX-45 (non-ionic surfactant) in the absence and presence of ionic liquid (1-hexyl-3-methylimidazolium chloride). The physicochemical parameters were estimated by the surface tension measurement. Various theoretical models (Clint, Rubingh, Motomura, and Maeda) were applied to determine the attractive behavior between drug and surfactant mixtures at the surface and in bulk. The drug and surfactant mixtures exhibit synergistic behavior in the absence and presence of ionic liquid. Several energetic parameters were also estimated with the assistance of regular solution approximation and pseudo phase separation model that indicate micelle formation and adsorption of surfactant at the surface is thermodynamically advantageous. The morphology of pure and mixture of amphiphiles has been estimated by the Tanford and Israelachvili theories. UV-visible spectroscopy was used to quantify the attractive behavior of the drug with surfactant with the help of a binding constant (K).

Interaction of Diphenhydramine Hydrochloride with Cationic and Anionic Surfactants: Mixed Micellization and Binding Studies.

The focus of the present work is to evaluate the interactions of an anti-allergic drug (diphenhydramine hydrochloride, DPH) with anionic (sodium dodecyl sulfate, SDS) and cationic (cetylpyridinium chloride, CPC) surfactants in the aqueous medium. The mixed micellization behavior and surface properties of drug-surfactant mixtures have been examined by surface tension measurements. Various theoretical approaches were applied to explore the synergistic or non-ideal behavior of the current mixed systems. Furthermore, the binding studies of drug with surfactants have been elaborated by UV-visible spectroscopy. Benesi-Hildebrand (B-H) theory was used to compute stoichiometric ratio, binding constant, and free energy change for the drug-surfactant mixtures. The outputs are deliberated taking into consideration the use of surfactants as capable drug delivery agents for DPH and hence advance bioavailability.

Synthesis and characterization of geminis and implications of their micellar solution on ninhydrin and metal amino acid complex.

In our study, three gemini dicationic surfactants with different methylene group spacer (16-6-16, 16-5-16 and 16-4-16) have been synthesized and characterized in solution by 1H NMR spectroscopic technique. The implications of gemini micellar solution on ninhydrin and metal amino acid complex ([Cu(II)-Trp]+) were performed by the means of single-beam UV-visible spectroscopy. The absorbance was noted at regular time intervals and values of rate constant (kψ ) were determined by using a computer-based program. Synthesized surfactants proved as an efficient catalyst on the interaction of ninhydrin with metal amino acid complex as compared with conventional surfactant and aqueous systems. The required description regarding the implications of gemini dicationic surfactants are provided in the text in detail. The conductivity technique was applied in order to get critical micelle concentration (cmc) of geminis in the presence and absence of reactants. Catalytic results developed in gemini dicationic surfactant system were explained effectively by pseudo-phase model. Various thermodynamic quantities, viz., activation energy, E a, activation enthalpy, ΔH #, and activation entropy, ΔS #, were obtained on interaction of ninhydrin with [Cu(II)-Trp]+ in gemini systems by applying Eyring equation. A detailed explanation about these evaluated parameters was also made.

Aggregation Behavior of Antipsychotic Drug under the Influence of Bile Salt in Aqueous/Urea Solution.

The self-assembly of pharmaceutical amphiphiles is an important area of research because of the involvement of these amphiphiles in physiological processes. The mixed micellization behavior of antipsychotic drug (chlorpromazine hydrochloride, CPZ) in the presence of bile salt (sodium cholate, SC) was studied by surface tension and fluorescence techniques in aqueous/urea solution. The output of the study has been analyzed by using different models (Clint, Rubingh, and Motomura) for mixed amphiphilic systems. The attractive or synergistic interactions between these two amphiphiles in water/urea were confirmed by the obtained data. Various thermodynamic parameters for the mixed micellization process have been computed and discussed.

Catalytic influence of 16-s-16 gemini surfactants on the rate constant of histidine and ninhydrin.

The present paper reports the catalytic influence of 16-s-16 (spacer (s) = 4, 5, 6) gemini surfactants on the rate constant of histidine and ninhydrin at 343 K and pH 5.0 using the spectrophotometric technique. The effect of varying amounts of geminis was made on the rate constant of histidine and ninhydrin keeping other constituents constant. Characteristics of the rate constant (kψ ) versus [gemini] depict the effect of surfactants on the rate constant. A systematic explanation about the effect of surfactants is revealed and discussed in the text. The influence of different parameters that includes [reactants], temperature and pH has also been performed on the study. In order to determine the critical micelle concentration (cmc) of pure surfactants and their solution mixtures, conductivity measurement was employed. By using the Eyring equation, activation parameters at different temperatures have been obtained. The resultant data of kψ versus [gemini] plot were rationalized with the pseudo-phase model of micelles.

Effects of temperature and polyols on the ciprofloxacin hydrochloride-mediated micellization of sodium dodecyl sulfate.

Herein, a conductivity method was engaged to explore the effects of a fluoroquinolone drug, namely ciprofloxacin hydrochloride (CFH)/CFH + polyols (organic compounds with multiple hydroxyl groups (glucose and fructose)), on the aggregation phenomenon of sodium dodecyl sulfate (SDS) at different temperatures (298.15-318.15 K) while maintaining a gap of 5 K. In this study, the critical micelle concentration (cmc) of the SDS/SDS + CFH mixture in water and polyols media was determined from plots of the specific conductivity versus the concentration of SDS to gain knowledge of the effects of CFH/CFH + polyols on the micelle formation behavior of SDS. The cmc value of the surfactant decreases in the presence of CFH in an aqueous medium; thus, CFH favors the micellization of SDS. The cmc values of SDS and the SDS + CFH mixture were enhanced in polyols media. The cmc values of SDS/SDS + CFH show a U-shaped behavior with temperature. The counterion dissociation (α) of the pure surfactant is higher in the presence of the drug and is further enhanced through an increase in the CFH concentration in water/polyols media. Different thermodynamic parameters, such as the Gibbs free energy of micellization , standard enthalpy , entropy , different transfer energies and enthalpy-entropy compensation parameters of micellization were determined and illustrated in detail to compare these parameters between the pure SDS and SDS + CFH mixture in polyols media. The negative values of for the SDS/SDS + CFH mixture in all cases indicate spontaneous micelle formation. The and values indicate the presence of both hydrophobic and electrostatic interactions amongst the studied components.

Influence of Cationic Cetyltrimethylammonium Bromide on Rate of Zn(II)-Histidine Complex and Ninhydrin.

Paper analyses the influence of cationic cetyltrimethylammonium bromide on rate of Zn(II)-histidine and ninhydrin. UV-visible spectroscopy was applied to note absorbance of Zn(II)-histidine complex with ninhydrin at the end of reaction in the two systems. Rate constant, kobs, (in aqueous) and rate constant, kψ, (in cetyltrimethylammonium bromide, CTAB) were determined by computer software. Reactions depict first-order in Zn(II)-histidine concentration and fractional-order in ninhydrin concentration in aqueous and micellar media. The results achieved indicate that the reactions take place principally by the same reaction mechanism in both the media. Critical micelle concentration of CTAB surfactant was calculated by recording the conductivity as a function of surfactant concentrations. Influence of various amounts of surfactant on Zn(II)-histidine complex and ninhydrin reaction was performed under different reaction conditions. Reaction was catalyzed and accelerated efficiently by surfactant medium compared to aqueous medium. The observed influence of surfactant on rate has been mentioned in details and their quantitative treatment of kinetic results have been deduced by the means of Menger and Portnoy model for micellar catalysis.