Natural polymeric nanoparticles as a non-invasive probe for mesenchymal stem cell labelling.

Non-invasive tracking of stem cells after transplant is necessary for cell therapy and tissue engineering field. Herein, we introduce natural and biodegradable nanoparticle to develop a highly efficient nanoprobe with the ability to penetrate the stem cell for tracking. Based on the use of (Gd³⁺) to label stem cells for magnetic resonance imaging (MRI) we synthesized nanoparticle-containing Gd³⁺. Gd³⁺ could be used as t₁-weighted MRI contrast agents. In this study, chitosan-alginate nanoparticles were synthesized as a clinical Dotarem^® carrier for decreased t₁-weighted. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR) were utilized for nanoprobe characterization and ICP analysis was performed for Gd³⁺ concentration measurement. The results illustrate that nanoprobes with spherical shape and with a size of 80 nm without any aggregation were obtained. Relaxivity results suggest that r₁ in the phantom was 12.8 mM⁻¹s⁻¹ per Gd³⁺ ion, which is 3.5 times larger than that for Dotarem^® (r₁ ∼3.6 mM⁻¹s⁻¹ per Gd³⁺ ion) and this result for synthesized nanoprobe in stem cells 3.56 mM⁻¹s⁻¹ per Gd³⁺ ion with 2.16 times larger than that for Dotarem^® was reported and also enhanced signal in in-vivo imaging was observed. Chitosan-alginate nanoparticles as a novel biocompatible probe for stem cell tracking can be utilized in tissue engineering approach. [ABSTRACT FROM AUTHOR]