Magnetic and Ultrasonic Guidance of Iron–Platinum Nanoparticles Encapsulated in Multifunctional Lipid Bubbles for Conquering the Blood‐Brain Barrier with Improved Theranostics
Authors: Chen William , Chan Ming-Hsien , Hsiao Michael 
Published: April 2020

Introduction

Glioblastoma multiforme (GBM) is one of the deadliest and most invasive brain/glioma cancers, and there is currently no established way to treat this disease. The treatment of GBM typically involves intracranial surgery sometimes followed by chemotherapy and/or radiation therapy. Intracranial treatment is difficult to accomplish; however, as the delivery of the treatment drug is impeded by the blood‐brain barrier (BBB). The BBB is a semipermeable barrier constructed by the brain tissue that prevents certain substances in the bloodstream from entering the brain.

Challenge

The treatment drug happens to be a substance that is prevented entry into the brain by the BBB and cannot pass through the BBB unassisted, which severely impedes its ability to treat GBM.

Action

In this study, we use a nanobubble (NB) embedding chemotherapeutic drug alongside a high‐intensity focused ultrasound (HIFU) oscillation to generate a cavitation impact on the BBB, which helps the drug bypass the BBB and reach the brain. The HIFU is a non‐invasive therapeutic technique that can be used to assist the delivery of drugs into the brain. Being an HIFU reagent, NBs have been proven by recent studies to generate an even more powerful cavitation effect due to the difference in composition and temporarily remove the BBB even more effectively due to the difference composition of NBs between the internal gaseous cavity and the liquid environment, which allows the drugs to pass through the BBB and reach the brain. Additionally, NBs also serve as carriers for functional nanoparticles to be loaded into the hydrophobic core. FePt nanoparticles are functional nanoparticles that produce high resolution images when observed under a T2‐weighted magnetic resonance imaging (MRI).

Resolution

Loading FePt nanoparticles into the hydrophobic core of NBs forms a bubble‐based drug delivery system (FePt@NB), and enables MRI to track the changes in GBM. The FePt@NB nanocomposite developed in this study represents a potential breakthrough in GBM treatment, through improved biological imaging and drug delivery into the brain tissue.

Support or Funding Information

This research was supported by Academia Sinica [AS‐SUMMIT‐108] to MH.

FePt has excellent T2‐weighted MRI imaging capabilities. As a hard magnetic material in a magnetic material, it has ferromagnetism and high magnetocrystalline anisotropy. The superparamagnetism of FePt NPs has made them attractive candidates to be used as MRI/CT scanning agents and high‐density recording material. This figure shows an MRI image evaluation experimental design of mice with FePt@NB material.

Figure 1

Protective barriers of the brain. The collective term “blood‐brain barrier” is used to describe four main interfaces between the central nervous system and the periphery. This research has demonstrated that FePt@NB can introduce a sensitive fluorescence signal in the brain. FePt@NB shows great MRI imaging and GBM therapy.

Figure 2