Engineering of Single Magnetic Particle Carrier for Living Brain Cell Imaging: A Tunable T₁-/T₂-/Dual-Modal Contrast Agent for Magnetic Resonance Imaging Application

Despite a variety of T 1 –T 2 dual-modal contrast agents (DMCAs) reported for magnetic resonance imaging (MRI), no tuning of local induced magnetic field strength of an DMCA, which is important to modulate the overall T 1 and T 2 responses for imaging delicate cells, tissues, and organs, is yet available. Here, we show that a spatial arrangement of T 1 and T 2 components within a “nano zone” in a single core–shell nanoparticle carrier (i.e., DMCA with core Fe 3 O 4 and MnO clusters in a silica shell) to produce the necessary fine-tuning effect. It is demonstrated that this particle after the anti-CD133 antibody immobilization allows both T 1 and T 2 imaging at higher resolution for living ependynmal brain cells of rodents with no local damage under a strong MRI magnetic field. This study opens a route to rational engineering of DMCAs for accurate magnetic manipulations in a safe manner.