Functionalized nanographene sheets with high antiviral activity through synergistic electrostatic and hydrophobic interactions

Schematic representation of synergistic action of electrostatic interactions of polyglycerol sulfate and conjugated aliphatic chains to the surface of nG-PGS.

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Molecular Recognition by Pillar[5]arenes: Evidence for Simultaneous Electrostatic and Hydrophobic Interactions

Pharmaceutics ◽

10.3390/pharmaceutics14010060 ◽

2021 ◽

Vol 14 (1) ◽

pp. 60

Author(s):

Borja Gómez-González ◽

Luis García-Río ◽

Nuno Basílio ◽

Juan C. Mejuto ◽

Jesus Simal-Gandara

Keyword(s):

Molecular Recognition ◽

Inclusion Complexes ◽

Electrostatic Interactions ◽

Alkyl Chain ◽

Hydrophobic Interactions ◽

Binding Constants ◽

Ionic Interactions ◽

Hydrophobic Effects ◽

Hydrophobic Character ◽

Electrostatic And Hydrophobic Interactions

The formation of inclusion complexes between alkylsulfonate guests and a cationic pillar[5]arene receptor in water was investigated by NMR and ITC techniques. The results show the formation of host-guest complexes stabilized by electrostatic interactions and hydrophobic effects with binding constants of up to 107 M−1 for the guest with higher hydrophobic character. Structurally, the alkyl chain of the guest is included in the hydrophobic aromatic cavity of the macrocycle while the sulfonate groups are held in the multicationic portal by ionic interactions.

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Interactions between adsorbents and adsorbates in aqueous solutions

Pure and Applied Chemistry ◽

10.1515/pac-2019-1110 ◽

2020 ◽

Vol 92 (10) ◽

pp. 1655-1662

Author(s):

Zhijian Wu ◽

Xiushen Ye ◽

Haining Liu ◽

Huifang Zhang ◽

Zhong Liu ◽

...

Keyword(s):

Hydrogen Bonding ◽

Ionic Strength ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Solution Ph ◽

Electrostatic And Hydrophobic Interactions

AbstractAdsorption is one of the most widely used processes in physicochemical operations. To design an adsorbent for a specific adsorbate, it is important to understand the interactions between adsorbents and adsorbates, which are very important for both adsorption capacity and selectivity. Electrostatic interactions, hydrogen bonding, hydrophobic interactions, complexation, and precipitation are comprehensively discussed. Adjusting solution pH and ionic strength is an effective method to improve the adsorption, especially when electrostatic and hydrophobic interactions are main interactions. With the increase in ionic strength, the hydrophobic interactions between adsorbents and adsorbates increase, while the electrostatic interactions decrease.

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Interaction of sulphone based reactive dyes with cationic surfactant: a spectroscopic and conductometric study

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2020-1706 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Misbah Iram ◽

Hamadia Sultana ◽

Muhammad Usman ◽

Bazgha Ahmad ◽

Nadia Akram ◽

...

Keyword(s):

Strong Interaction ◽

Cetyltrimethylammonium Bromide ◽

Hydrophobic Interactions ◽

Reactive Dyes ◽

Micellar System ◽

Palisade Layer ◽

Micellar Systems ◽

Gibbs Energies ◽

Electrostatic And Hydrophobic Interactions ◽

Conductometric Study

Abstract Interaction of sulphone based reactive dyes, designated as dye-1 and dye-2, with cationic micellar system of cetyltrimethylammonium bromide (CTAB), has been investigated by spectroscopic and conductometeric measurements. Efficiency of the selected micellar systems is assessed by the values of binding constant (K b ), partition coefficient (K x ) and respective Gibbs energies. Critical micelle concentration (CMC) of surfactant, electrostatic and hydrophobic interactions as well as polarity of the medium plays significant role in this phenomenon. The negative values of Gibbs energies of binding (∆G b ) and partition (∆G p ) predicts the feasibility and spontaneity of respective processes. Similarly negative values of ∆G m and ∆H m and positive values of ∆S m , calculated from conductometeric data, further, revealed the exothermicity, spontaneity and, thus, stability of system. The results, herein, have disclosed the strong interaction between dye and surfactant molecules. The dye-2 has been observed to be solubilized to greater extent, as compared to dye 1, due to strong interaction ith hydrophiles of CTAB and accommodation of its molecules in palisade layer of micelle closer to the micelle/water interface.

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Characterization of Virus Adsorption by Using DEAE-Sepharose and Octyl-Sepharose

Applied and Environmental Microbiology ◽

10.1128/aem.68.8.3965-3968.2002 ◽

2002 ◽

Vol 68 (8) ◽

pp. 3965-3968 ◽

Cited By ~ 26

Author(s):

Patricia A. Shields ◽

Samuel R. Farrah

Keyword(s):

Sodium Chloride ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Chloride Concentration ◽

Sodium Chloride Concentration ◽

Virus Adsorption ◽

Nacl Concentration

ABSTRACT Viruses were characterized by their adsorption to DEAE-Sepharose or by their elution from octyl-Sepharose by using buffered solutions of sodium chloride with different ionic strengths. Viruses whose adsorption to DEAE-Sepharose was reduced most rapidly by an increase in the sodium chloride concentration were considered to have the weakest electrostatic interactions with the solids; these viruses included MS2, E1, and φX174. Viruses whose adsorption to DEAE-Sepharose was reduced least rapidly were considered to have the strongest electrostatic interactions with the column; these viruses included P1, T4, T2, and E5. All of the viruses studied adsorbed to octyl-Sepharose in the presence of 4 M NaCl. Viruses that were eluted most rapidly following a decrease in the concentration of NaCl were considered to have the weakest hydrophobic interactions with the column; these viruses included φX174, CB4, and E1. Viruses that were eluted least rapidly from the columns after the NaCl concentration was decreased were considered to have the strongest hydrophobic interactions with the column; these viruses included f2, MS2, and E5.

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Protein-Based Nanohydrogels for Bioactive Delivery

Frontiers in Chemistry ◽

10.3389/fchem.2021.573748 ◽

2021 ◽

Vol 9 ◽

Author(s):

Subhash Chander ◽

Giriraj T. Kulkarni ◽

Neerupma Dhiman ◽

Harsha Kharkwal

Keyword(s):

Drug Delivery ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Biological Fluids ◽

Three Dimensional ◽

Covalent Bond ◽

Ionic Concentration ◽

Covalent Bonds ◽

Encapsulation Process ◽

Insightful Analysis

Hydrogels possess a unique three-dimensional, cross-linked network of polymers capable of absorbing large amounts of water and biological fluids without dissolving. Nanohydrogels (NGs) or nanogels are composed of diverse types of polymers of synthetic or natural origin. Their combination is bound by a chemical covalent bond or is physically cross-linked with non-covalent bonds like electrostatic interactions, hydrophobic interactions, and hydrogen bonding. Its remarkable ability to absorb water or other fluids is mainly attributed to hydrophilic groups like hydroxyl, amide, and sulphate, etc. Natural biomolecules such as protein- or peptide-based nanohydrogels are an important category of hydrogels which possess high biocompatibility and metabolic degradability. The preparation of protein nanohydrogels and the subsequent encapsulation process generally involve use of environment friendly solvents and can be fabricated using different proteins, such as fibroins, albumin, collagen, elastin, gelatin, and lipoprotein, etc. involving emulsion, electrospray, and desolvation methods to name a few. Nanohydrogels are excellent biomaterials with broad applications in the areas of regenerative medicine, tissue engineering, and drug delivery due to certain advantages like biodegradability, biocompatibility, tunable mechanical strength, molecular binding abilities, and customizable responses to certain stimuli like ionic concentration, pH, and temperature. The present review aims to provide an insightful analysis of protein/peptide nanohydrogels including their preparation, biophysiochemical aspects, and applications in diverse disciplines like in drug delivery, immunotherapy, intracellular delivery, nutraceutical delivery, cell adhesion, and wound dressing. Naturally occurring structural proteins that are being explored in protein nanohydrogels, along with their unique properties, are also discussed briefly. Further, the review also covers the advantages, limitations, overview of clinical potential, toxicity aspects, stability issues, and future perspectives of protein nanohydrogels.

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In vitro activity of human recombinant alpha-2b interferon against SARS-CoV-2 virus

Voprosy Virusologii ◽

10.36233/0507-4088-13 ◽

2021 ◽

Vol 66 (2) ◽

pp. 123-128

Author(s):

S. Ya. Loginova ◽

V. N. Shсhukina ◽

S. V. Savenko ◽

S. V. Borisevich

Keyword(s):

Cell Culture ◽

Antiviral Activity ◽

Viral Infections ◽

Complete Suppression ◽

Antiviral Efficacy ◽

Prevention And Treatment ◽

Proven Efficacy ◽

High Antiviral Activity

Introduction. The pandemic spread of a new coronavirus infection, COVID-19, has caused a global emergency and attracted the attention of public health professionals and the population of all countries. A significant increase in the number of new cases of SARS-CoV-2 infection demonstrates the urgency of finding drugs effective against this pathogen.The aim of this work was to evaluate the in vitro antiviral efficacy of human recombinant alpha-2b interferon (IFN-α2b) against SARS-CoV-2 virus.Material and methods. The experiments had been carried out on Vero Cl008, the continuous line of African green monkey (Chlorocebus sabaeus) kidney cells. The effectiveness of the drugs was assessed by the suppression of viral reproduction in vitro. The biological activity was determined using titration of a virus-containing suspension in a Vero Cl008 cell culture by the formation of negative colonies.Results. The antiviral efficacy of the IFN-α2b-based medications, which have a high safety profile and proven efficacy in the prevention and treatment of influenza and acute respiratory viral infections (ARVI), has been studied against the new pandemic SARS-CoV-2 virus in vitro experiments in Vero C1008 cell culture. IFN-α2b effectively inhibits the reproduction of the virus when applied both 24 hrs before and 2 hrs after infection. In the IFN-α2b concentration range 102–106 IU/ml a complete suppression of the reproduction of the SARS-CoV-2 virus had been demonstrated.Discussion. IFN-α2b demonstrated in vitro high antiviral activity against SARS-CoV-2. In addition, the substance has a high chemotherapeutic index (>1000).Conclusion. Medications for intranasal use based on IFN-α2b have high antiviral activity and are promising drugs for in vivo study in terms of prevention and treatment of COVID-19.

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Anti-Hepatitis B Virus Activity of New 1,2,4-Triazol-2-yl- and 1,3,4-Oxadiazol-2-yl-2-pyridinone Derivatives

Zeitschrift für Naturforschung C ◽

10.1515/znc-2008-9-1010 ◽

2008 ◽

Vol 63 (9-10) ◽

pp. 667-674 ◽

Cited By ~ 12

Author(s):

Farag A. El-Essawy ◽

Wael A. El-Sayed ◽

Sherif A. El-Kafrawy ◽

Asmaa S. Morshedy ◽

Adel-H. Abdel-Rahman

Keyword(s):

Sulfuric Acid ◽

Hepatitis B Virus ◽

Hepatitis B ◽

Antiviral Activity ◽

Alkylating Agents ◽

Acid Hydrazide ◽

Virus Activity ◽

B Virus ◽

Thiadiazole Derivative ◽

High Antiviral Activity

A number of 1,3,4-oxadiazole, 3 - 9, and 1,2,4-triazole derivatives, 13 - 15, were synthesized starting form the acid hydrazide 1. The 1,3,4-thiadiazole derivative 12 was prepared from the substituted phenylthiosemicarbazide derivative 11 by treatment with sulfuric acid. The aryl hydrazone derivatives 10a - c were synthesized by reaction of the hydrazide 1 with the corresponding ketones. The thioalkyl derivatives 16a - e were prepared by akylation of the thiol derivatives 3 and 13 with different alkylating agents. The newly synthesized compounds were tested for their anti-HBV activity and some of these compounds showed high antiviral activity

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Bone Morphogenetic Protein 2 (BMP-2) Aggregates Can be Solubilized by Albumin—Investigation of BMP-2 Aggregation by Light Scattering and Electrophoresis

Pharmaceutics ◽

10.3390/pharmaceutics12121143 ◽

2020 ◽

Vol 12 (12) ◽

pp. 1143

Author(s):

Julius Sundermann ◽

Holger Zagst ◽

Judith Kuntsche ◽

Hermann Wätzig ◽

Heike Bunjes

Keyword(s):

Light Scattering ◽

Bone Morphogenetic Protein ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Pharmaceutical Research ◽

Bone Morphogenetic Protein 2 ◽

Growth Factor Delivery ◽

Surface Charges ◽

High Tendency ◽

Morphogenetic Protein

Bone morphogenetic protein 2 (BMP-2) has a high tendency to aggregate at physiological pH and physiological ionic strength, which can complicate the development of growth factor delivery systems. The aggregation behavior in differently concentrated BMP-2 solutions was investigated using dynamic and static light scattering. It was found that at higher concentrations larger aggregates are formed, whose size decreases again with increasing dilution. A solubilizing effect and therefore less aggregation was observed upon the addition of albumin. Imaged capillary isoelectric focusing and the simulation of the surface charges of BMP-2 were used to find a possible explanation for the unusually low solubility of BMP-2 at physiological pH. In addition to hydrophobic interactions, attractive electrostatic interactions might be decisive in the aggregation of BMP-2 due to the particular distribution of surface charges. These results help to better understand the solubility behavior of BMP-2 and thus support future pharmaceutical research and the development of new strategies for the augmentation of bone healing.

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