Applications of Isothermal Titration Calorimetry in Studying Biomimetic Nanocarriers
Martin Guerrero, C. Braden, Yuping Bao
Abstract
Biomimetic nanocarriers, particularly membrane-based systems, have emerged as promising platforms for drug delivery. A thorough understanding of the molecular interactions that govern their assembly, stability, and cargo-loading efficiency is essential for optimizing their design and performance. Equally important are their interactions with biological components such as proteins, lipids, nucleotides, and cells, which significantly influence delivery efficacy. Among various techniques for characterizing these nanocarriers, isothermal titration calorimetry (ITC) has proven to be an invaluable tool to study their molecular interactions. ITC enables direct quantification of key thermodynamic parameters, such as binding affinity, stoichiometry, enthalpy, and entropy changes, without the need for molecular labeling or immobilization. This review highlights the application of ITC in the study of biomimetic nanocarriers, focusing on solid lipid nanoparticles, liposomes, extracellular vesicles, cell-derived vesicles and live cells. For each type of nanocarrier, the ITC applications in specific areas and the resulting information are discussed. For example, ITC was used to characterize drug interaction and protein adsorption for solid nanoparticles. In contrast, many aspects of liposomes were explored by ITC, including membrane solubilization and stabilization, peptide interactions, and macromolecule and protein adsorption. Overall, this review aims to provide a conceptual and practical framework for employing ITC in the investigation of biomimetic nanocarrier systems, facilitating their rational design and improved therapeutic performance. Furthermore, the discussion encourages further development of strategies to increase the application in cell-derived vesicles and live cells.