Intermolecular interactions play a role in the distribution and transport of charged contrast agents in a cartilage model

• Published in: PloS one Vol. 14; no. 10; p. e0215047
• Main Authors: Algotsson, Jenny, Jönsson, Peter, Forsman, Jan, Topgaard, Daniel, Söderman, Olle
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 03.10.2019; Public Library of Science (PLoS)
• Subjects: Antiarthritic agents; Arthritis; Basic Medicine; Biological Transport, Active; Biology and Life Sciences; Biomechanics; Biomedical materials; Care and treatment; Cartilage; Cartilage (articular); Cartilage diseases; Cartilage, Articular - diagnostic imaging; Cartilage, Articular - metabolism; Cartilage, Articular - pathology; Clinical Medicine; Computer simulation; Contrast agents; Contrast media; Contrast Media - chemistry; Contrast Media - pharmacokinetics; Contrast Media - pharmacology; Diagnosis; Differential equations; Electrostatic properties; Extracellular matrix; Humans; Klinisk medicin; Läkemedelskemi; Magnetic resonance; Magnetic Resonance Imaging; Medical and Health Sciences; Medical examination; Medical treatment; Medicin och hälsovetenskap; Medicinal Chemistry; Medicine and Health Sciences; Medicinska och farmaceutiska grundvetenskaper; Methods; Models, Biological; Monte Carlo methods; Monte Carlo simulation; NMR; Nuclear magnetic resonance; Orthopaedics; Orthopedics; Ortopedi; Osteoarthritis; Osteoarthritis - diagnostic imaging; Osteoarthritis - metabolism; Osteoarthritis - pathology; Physical chemistry; Physical examinations; Physical Sciences; Polyelectrolytes; Radiologi och bildbehandling; Radiology and Medical Imaging; Radiology, Nuclear Medicine and Medical Imaging; Research and analysis methods; Solutes; Species; Synovial fluid; Synovial Fluid - diagnostic imaging; Synovial Fluid - metabolism; Theoretical analysis; Transport; Sweden
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0215047

The transport and distribution of charged molecules in polyelectrolyte solutions are of both fundamental and practical importance. A practical example, which is the specific subject addressed in the present paper, is the transport and distribution of charged species into cartilage. The charged species could be a contrast agent or a drug molecule involved in diagnosis or treatment of the widespread degenerative disease osteoarthritis, which leads to degradation of articular cartilage. Associated scientific issues include the rate of transport and the equilibrium concentrations of the charged species in the cartilage and the synovial fluid. To address these questions, we present results from magnetic resonance micro-imaging experiments on a model system of articular cartilage. The experiments yield temporally and spatially resolved data on the transport of a negatively charged contrast agent (charge = -2), used in medical examinations of cartilage, into a polyelectrolyte solution, which is designed to capture the electrostatic interactions in cartilage. Also presented is a theoretical analysis of the transport where the relevant differential equations are solved using finite element techniques as well as treated with approximate analytical expressions. In the analysis, non-ideal effects are included in the treatment of the mobile species in the system. This is made possible by using results from previous Monte Carlo simulations. The results demonstrate the importance of taking non-idealities into account when data from measurements of transport of charged solutes in a system with fixed charges from biological polyelectrolytes are analyzed.