Dual-phase model: Estimating the temperature and hydrodynamic size of magnetic nanoparticles with protein-corona formation

Abstract

The use of magnetic nanothermometry faces challenges in noninvasive thermal monitoring during hyperthermia therapy due to the impact of the biological protein corona. Herein, we present an advanced magnetic nanothermometry model that incorporates the linear and cubic susceptibility phases, ensures robustness against hydrodynamic variations, maintains concentration independence, and can adapt to diverse magnetic field intensities. In this work, we studied five types of particles with comparable core structures (single- and multi-core) and chemical compositions (carboxyl and plain) before and after incubation with bovine serum albumin. Temperature-measurement experiments were conducted spanning both room temperature and a physiological temperature range of 10 K. The results highlight the model's effectiveness, especially for single-core particles exhibiting Brownian relaxation behavior, with temperature errors controlled to within ±0.4 K. The model's predictions remained consistent irrespective of particle chemical compositions, while detecting hydrodynamic diameter changes post-incubation, indirectly highlighting protein–corona interactions. These findings enhance the application potential of magnetic nanothermometry in hyperthermia therapy, contributing to preclinical validations and insights into nanoparticle–biological interactions.