scholarly journals Theoretical Considerations and the Microelectrophoresis Experiment on the Influence of Selected Chaotropic Anions on Phosphatidylcholine Membrane Surface Charge Density

Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 132
Author(s):  
Joanna Kotyńska ◽  
Monika Naumowicz
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Surface Charge Density ◽  
Membrane Surface ◽  
Quantitative Description ◽  
Theoretical Data ◽  
Lipid Vesicles ◽  
Hofmeister Series ◽  
Chaotropic Anions ◽  
Membrane Surface Charge

Influence of sodium salts of selected chaotropic anions from the Hofmeister series (NaCl, NaBr, NaNO3, NaI) on the surface charge density of phosphatidylcholine membranes was studied. Small unilamellar lipid vesicles were used as a model system in the investigations. The theoretical and experimental approach to the interactions between inorganic anions and phosphatidylcholine membranes is presented. Experimental membrane surface charge densities data were determined as a function of pH of the aqueous electrolytes using microelectrophoresis method. The quantitative description of the interactions between zwitterionic phosphatidylcholine membrane and monovalent anions is presented. The equilibria constants of the binding of solution ions onto phospholipid surface were calculated. Knowledge of these parameters was essential to determine the theoretical membrane surface charge density values. The theoretical data were compared to the experimental ones in order to verify the mathematical model. Both approaches indicate that the anion-phosphatidylcholine membrane interaction increases with the size of the anion. The adsorption of chaotropic anions to membranes was found to follow the Hofmeister series I− > NO3− > Br− > Cl−.

scholarly journals Monitoring of the Surface Charge Density Changes of Human Glioblastoma Cell Membranes upon Cinnamic and Ferulic Acids Treatment

2020 ◽  
Vol 21 (18) ◽  
pp. 6972 ◽  
Author(s):  
Monika Naumowicz ◽  
Magdalena Kusaczuk ◽  
Marcin Zając ◽  
Miroslav Gál ◽  
Joanna Kotyńska
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Phenolic Acids ◽  
Surface Charge Density ◽  
Membrane Surface ◽  
Theoretical Data ◽  
Beneficial Effects ◽  
Ph Values ◽  
Ic50 Values ◽  
Human Gbm

Cinnamic acid (CA) and ferulic acid (FA) are naturally occurring phenolic acids claimed to exert beneficial effects against disorders related to oxidative stress, including cancer. One such malignancy that still remains a therapeutic challenge mainly due to its heterogeneity and inaccessibility to therapeutic agents is Glioblastoma multiforme (GBM). Here, the influence of CA and FA on the surface charge density of human GBM cell line LN-229 was studied using the electrophoretic light scattering technique. Also, the cytotoxicity of both phenolic acids was determined by metabolic activity-assessing tetrazolium test (MTT) analysis after exposure to CA and FA for 24 h and 48 h. Results showed that both compounds reduced cell viability of LN-229 cells, with more pronounced effect evoked by CA as reflected in IC50 values. Further analyses demonstrated that, after treatment with both phenolic acids, the negative charge of membranes decreased at high pH values and the positive charge of the membranes increased at low pH values compared to the data obtained for untreated cells. Afterward, a four-equilibrium model was applied to estimate the total surface concentrations of both acidic and basic functional groups and their association constants with solution ions in order to calculate theoretical values of membrane surface charge densities. Then, the theoretical data were compared to the experimental data in order to verify the mathematical model. As such, our results indicate that application of electrochemical methods to determine specific drug–membrane interactions might be crucial for predicting their pharmacological activity and bioavailability.

Charge Characteristics of Nanofiltration Membrane by Streaming Potential Method

2011 ◽  
Vol 396-398 ◽  
pp. 547-551 ◽  
Author(s):  
Bao Wei Su ◽  
Xiao Jie Duan ◽  
Mao Wei Dou ◽  
Xue Li Gao ◽  
Cong Jie Gao
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Surface Charge Density ◽  
Electrostatic Interactions ◽  
Membrane Surface ◽  
Streaming Potential ◽  
Freundlich Isotherm ◽  
Potential Method ◽  
Nanofiltration Membrane ◽  
Membrane Surface Charge

Surface charge properties of DL nanofiltration membrane were studied using streaming potential method. The results indicate that in the experimental concentration range, the relationship between NF membrane surface charge density and electrolyte solution concentration is in good agreement with Freundlich-isotherm adsorption, which indicates that the membrane surface charge comes from the adsorption of ions of the solution. In addition, the analysis of anion and cation adsorption on nanofiltration membrane surface showed that adsorption of common ions to the Inner Helmholtz Plane through specific adsorption increases the charge density, while adsorption of counter ions to the Outer Helmholtz Plane through electrostatic interactions leads to electric double-layer contracting inward, decreasing the membrane surface charge density.

scholarly journals Effect of Selected Anionic and Cationic Drugs Affecting the Central Nervous System on Electrical Properties of Phosphatidylcholine Liposomes: Experiment and Theory

2021 ◽  
Vol 22 (5) ◽  
pp. 2270
Author(s):  
Joanna Kotyńska ◽  
Monika Naumowicz
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Charge Density ◽  
Surface Charge ◽  
Surface Charge Density ◽  
Barbituric Acid ◽  
Membrane Surface ◽  
Adsorption Equilibria ◽  
Two Component ◽  
The Central Nervous System

Interactions between phospholipid membranes and selected drugs affecting the central nervous system (CNS) were investigated. Small, unilamellar liposomes were used as biomimetic cell membrane models. Microelectrophoretic experiments on two-component liposomes were performed using the electrophoretic light scattering technique (ELS). The effect of both positively (perphenazine, PF) and negatively (barbituric acid, BA) charged drugs on zwitterionic L-α-phosphatidylcholine (PC) membranes were analyzed. Experimental membrane surface charge density (d) data were determined as a function of pH. Quantitative descriptions of the adsorption equilibria formed due to the binding of solution ions to analyzed two-component membranes are presented. Binding constants of the solution ions with perphenazine and barbituric acid-modified membranes were determined. The results of our research show that both charged drugs change surface charge density values of phosphatidylcholine membranes. It can be concluded that perphenazine and barbituric acid are located near the membrane surface, interacting electrostatically with phosphatidylcholine polar heads.

Sign in / Sign up

Export Citation Format

Share Document