[Paper Review] Novel multifunctional 90Y-labelled albumin magnetic microspheres for cancer therapy

Sanja Vranješ‐Đurić, Magdalena Radović+10 more|arXiv (Cornell University)|May 11, 2012

Nanoparticle-Based Drug Delivery52 references19 citations

TL;DR

This study develops yttrium-90-labeled human serum albumin magnetic microspheres (90Y-HSAMMS) using a modified emulsification-heat stabilization method, incorporating citric acid-coated magnetite nanoparticles for superparamagnetic behavior. The microspheres show high radiolabel stability in saline and human serum, with 82.67% of 90Y activity retained in the lungs of rats after 72 hours, demonstrating strong potential for bimodal radionuclide-hyperthermia cancer therapy.

ABSTRACT

We present in vitro and in vivo studies of yttrium-90 (90Y)-labelled human serum albumin magnetic microspheres (HSAMMS) as multifunctional agent for bimodal radionuclide-hyperthermia cancer therapy. The HSAMMS were produced using a modified emulsification-heat stabilization technique and contained 10-nm magnetite nanoparticles coated with citric acid, distributed as inhomogeneous clusters within the albumin microspheres. The average particle size of the complete HSAMMS was 20 (mu)m, and they exhibited superparamagnetic behavior at room temperature. The stability of the 90^Y-labelled HSAMMS was investigated in vitro (in saline and human serum) and in vivo by analyzing their biodistribution in normal Wistar rats. The in vitro experiments revealed the high stability of the labelled HSAMMS in saline and human serum after 72 h. Following the intravenous administration of the 90^Y-HSAMMS in rats, 88.81% of the activity localizes in the lungs after 1 h, with 82.67% remaining after 72 h. These data on 90Y-HSAMMS provide good evidence for their potential use in bimodal radionuclide-hyperthermia cancer therapy.

Motivation & Objective

• To develop a multifunctional therapeutic agent combining radionuclide therapy and magnetic hyperthermia for cancer treatment.
• To enhance targeting and retention of therapeutic radionuclides in tumor tissues using magnetic microspheres.
• To evaluate the in vitro and in vivo stability of 90Y-labeled HSAMMS in physiological conditions.
• To assess biodistribution and retention of 90Y-HSAMMS in a rat model to determine therapeutic potential.
• To demonstrate the feasibility of using superparamagnetic albumin microspheres for dual-mode cancer therapy.

Proposed method

• Synthesis of HSAMMS via a modified emulsification-heat stabilization technique to embed 10-nm citric acid-coated magnetite nanoparticles.
• Radiolabeling of the microspheres with 90Y using standard chelation techniques to ensure stable binding.
• Characterization of microsphere size (20 µm average) and superparamagnetic behavior at room temperature.
• In vitro stability testing in saline and human serum over 72 hours to assess radiolabel retention.
• In vivo biodistribution study in normal Wistar rats following intravenous administration of 90Y-HSAMMS.
• Quantitative analysis of radioactivity in organs, particularly the lungs, at 1 hour and 72 hours post-injection.

Experimental results

Research questions

• RQ1 Can 90Y-labeled HSAMMS be stably produced with consistent superparamagnetic properties for dual therapy?
• RQ2 How stable is the 90Y-label on HSAMMS in human serum and saline over 72 hours?
• RQ3 What is the biodistribution pattern of 90Y-HSAMMS in vivo, particularly in the lungs after intravenous injection?
• RQ4 To what extent does 90Y-HSAMMS retain activity in the lungs after 72 hours, indicating potential for sustained tumor targeting?
• RQ5 Can HSAMMS serve as a viable platform for combined radionuclide and hyperthermia cancer therapy?

Key findings

• The 90Y-HSAMMS exhibited high stability in saline and human serum, with no significant loss of radioactivity after 72 hours.
• After 1 hour post-injection, 88.81% of the administered 90Y activity localized in the lungs of Wistar rats.
• After 72 hours, 82.67% of the initial 90Y activity remained in the lungs, indicating prolonged retention.
• The microspheres had an average diameter of 20 µm, suitable for pulmonary targeting.
• The presence of 10-nm citric acid-coated magnetite nanoparticles conferred superparamagnetic behavior at room temperature.
• The in vivo results support the potential of 90Y-HSAMMS for bimodal radionuclide-hyperthermia therapy due to favorable biodistribution and stability.