REMOVED: Mechanistic Modeling of Protein Ultrafiltration: The Role of Small Counter–ions in Protein Transfer

Characterization of tumor growth dynamics is of major importance for cancer understanding. By contrast with phenomenological approaches, mechanistic modeling can facilitate disclosing underlying tumor mechanisms and lead to identification of physical factors affecting proliferation and invasive behavior. Current mathematical models are often formulated at the tissue or organ scale with the scope of a direct clinical usefulness. Consequently, these approaches remain empirical and do not allow gaining insight into the tumor properties at the scale of small cell aggregates. Here, experimental and numerical studies of the dynamics of tumor aggregates are performed to propose a physics-based mathematical model as a general framework to investigate tumor microenvironment. The quantitative data extracted from the cellular capsule technology microfluidic experiments allow a thorough quantitative comparison with in silico experiments. This dual approach demonstrates the relative impact of oxygen and external mechanical forces during the time course of tumor model progression.

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Role of the alkyl moiety and counter ions on the thermal stability of chitosan derivatives

Journal of Applied Polymer Science ◽

10.1002/app.33545 ◽

2011 ◽

Vol 121 (2) ◽

pp. 815-822 ◽

Cited By ~ 2

Author(s):

Douglas de Britto ◽

Sergio Paulo Campana Filho ◽

Odilio B. G. Assis

Keyword(s):

Thermal Stability ◽

Chitosan Derivatives ◽

Counter Ions ◽

Alkyl Moiety ◽

Thermal Stability Of

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Capacitance Enhancement by Incorporation of Functionalised Carbon Nanotubes into Poly(3,4-Ethylenedioxythiophene)/Graphene Oxide Composites

Materials ◽

10.3390/ma13102419 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2419

Author(s):

Anita Cymann ◽

Mirosław Sawczak ◽

Jacek Ryl ◽

Ewa Klugmann-Radziemska ◽

Monika Wilamowska-Zawłocka

Keyword(s):

Carbon Nanotubes ◽

Graphene Oxide ◽

Electrochemical Performance ◽

Polymer Chains ◽

Electrodeposition Process ◽

Counter Ions ◽

Oxide Composites ◽

Electrochemical Characterisation ◽

Synthesis Solution

This paper reports on the role of oxidised carbon nanotubes (oxMWCNTs) present in poly-3,4-ethylenedioxytiophene (PEDOT)/graphene oxide (GOx) composite. The final ternary composites (pEDOT/GOx/oxMWCNTs) are synthesised by an electrodeposition process from the suspension-containing monomer, oxidised carbon nanotubes and graphene oxide. Dissociated functional groups on the surface of graphene oxide play a role of counter-ions for the polymer chains. Detailed physicochemical and electrochemical characterisation of the ternary composites is presented in the paper. The results prove that the presence of oxMWCNTs in the ternary composites doubles the capacitance values compared to the binary ones (450 vs. 270 F cm−3 for PEDOT/GOx/oxMWCNTs and PEDOT/GOx, respectively). The amount of carbon nanotubes in the synthesis solution is crucial for physicochemical properties of the composites, their adhesion to the electrode substrate and the electrochemical performance.

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The Role of Counter-Ions in Peptides—An Overview

Pharmaceuticals ◽

10.3390/ph13120442 ◽

2020 ◽

Vol 13 (12) ◽

pp. 442

Author(s):

Karol Sikora ◽

Maciej Jaśkiewicz ◽

Damian Neubauer ◽

Dorian Migoń ◽

Wojciech Kamysz

Keyword(s):

Mobile Phase ◽

Analytical Techniques ◽

Drug Formulation ◽

Biological Processes ◽

Multiple Functions ◽

Mobile Phase Additives ◽

Counter Ions ◽

Living Organisms ◽

The Impact

Peptides and proteins constitute a large group of molecules that play multiple functions in living organisms. In conjunction with their important role in biological processes and advances in chemical approaches of synthesis, the interest in peptide-based drugs is still growing. As the side chains of amino acids can be basic, acidic, or neutral, the peptide drugs often occur in the form of salts with different counter-ions. This review focuses on the role of counter-ions in peptides. To date, over 60 peptide-based drugs have been approved by the FDA. Based on their area of application, biological activity, and results of preliminary tests they are characterized by different counter-ions. Moreover, the impact of counter-ions on structure, physicochemical properties, and drug formulation is analyzed. Additionally, the application of salts as mobile phase additives in chromatographic analyses and analytical techniques is highlighted.

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