Development of a Coflowing Device for the Size-Controlled Preparation of Magnetic-Polymeric Microspheres as Embolization Agents in Magnetic Resonance Navigation Technology

Nosrati, Zeynab; Li, Ning; Michaud, François; Ranamukhaarachchi, Sahan A.; Karagiozov, Stoyan; Soulez, Gilles; Saatchi, Katayoun; Häfeli, Urs O.

doi:10.1021/acsbiomaterials.7b00839

Cited by 28 publications

(21 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The MMPs used in this experiment are composed of Fe 3 O 4 nanoparticles embedded in a poly(lactic‐co‐glycolic acid) (PLGA) matrix in which a chemotherapeutic agent of choice can be infused. Their size was 200 ± 20 μm and their magnetization saturation value was 30 emu/g …”

Section: Methodsmentioning

confidence: 99%

Selective embolization with magnetized microbeads using magnetic resonance navigation in a controlled‐flow liver model

Michaud

Plantefève

et al. 2018

Medical Physics

Self Cite

View full text Add to dashboard Cite

Purpose The purpose of this study was to demonstrate the feasibility of using a custom gradient sequence on an unmodified 3T magnetic resonance imaging (MRI) scanner to perform magnetic resonance navigation (MRN) by investigating the blood flow control method in vivo, reproducing the obtained rheology in a phantom mimicking porcine hepatic arterial anatomy, injecting magnetized microbead aggregates through an implantable catheter, and steering the aggregates across arterial bifurcations for selective tumor embolization. Materials and Methods In the first phase, arterial hepatic velocity was measured using cine phase‐contrast imaging in seven pigs under free‐flow conditions and controlled‐flow conditions, whereby a balloon catheter is used to occlude arterial flow and saline is injected at different rates. Three of the seven pigs previously underwent selective lobe embolization to simulate a chemoembolization procedure. In the second phase, the measured in vivo controlled‐flow velocities were approximately reproduced in a Y‐shaped vascular bifurcation phantom by injecting saline at an average rate of 0.6 mL/s with a pulsatile component. Aggregates of 200‐μm magnetized particles were steered toward the right or left hepatic branch using a 20‐mT/m MRN gradient. The phantom was oriented at 0°, 45°, and 90° with respect to the B0 magnetic field. The steering differences between left–right gradient and baseline were calculated using Fisher's exact test. A theoretical model of the trajectory of the aggregate within the main phantom branch taking into account gravity, magnetic force, and hydrodynamic drag was also designed, solved, and validated against the experimental results to characterize the physical limitations of the method. Results At an injection rate of 0.5 mL/s, the average flow velocity decreased from 20 ± 15 to 8.4 ± 5.0 cm/s after occlusion in nonembolized pigs and from 13.6 ± 2.0 to 5.4 ± 3.0 cm/s in previously embolized pigs. The pulsatility index measured to be 1.7 ± 1.8 and 1.1 ± 0.1 for nonembolized and embolized pigs, respectively, decreased to 0.6 ± 0.4 and 0.7 ± 0.3 after occlusion. For MRN performed at each orientation, the left–right distribution of aggregates was 55%, 25%, and 75% on baseline and 100%, 100%, and 100% (P < 0.001, P = 0.003, P = 0.003) after the application of MRN, respectively. According to the theoretical model, the aggregate reaches a stable transverse position located toward the direction of the gradient at a distance equal to 5.8% of the radius away from the centerline within 0.11 s, at which point the aggregate will have transited through a longitudinal distance of 1.0 mm from its release position. Conclusion In this study, we showed that the use of a balloon catheter reduces arterial hepatic flow magnitude and variation with the aim to reduce steering failures caused by fast blood flow rates and low magnetic steering forces. A mathematical model confirmed that the reduced flow rate is low enough to maximize steering ratio. After reproducing the flow rate in a vascular bifur...

show abstract

Section: Methodsmentioning

confidence: 99%

Selective embolization with magnetized microbeads using magnetic resonance navigation in a controlled‐flow liver model

Michaud

Plantefève

et al. 2018

Medical Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…In order to overcome this problem, Nosrati et al (2018) embedded magnetic iron oxide nanoparticles in a poly(lactic- co -glycolic acid) (PLGA) microsphere matrix using droplet microfluidics technology (as shown in Figure 4A), to fabricate homogeneous magnetic microbeads in a size range of 130–700 μm (as shown in Figure 4B). This gave potential to precisely monitor and control the accumulation of microbeads at disease vessel sites.…”

Section: Composite Microbeads Made Of Magnetic Nanoparticles and Polymentioning

confidence: 99%

“…(B) Scanning electron microscopy observation of magnetic microparticles embedding (b-1) 50 wt% magnetic iron oxide nanoparticles and (b-2) 60 wt% magnetic iron oxide nanoparticles. [Reproduced with permission from Nosrati et al (2018), Copyright 2018 American Chemical Society]. (C) Fabrication of magnetic PLGA-MMs (PLGA-magnetic microspheres) by emulsion of PLGA polymer and iron oxide magnetic nanoparticles, which was utilized as liver arterial embolization agent in VX2 liver tumor of rabbit.…”

Section: Composite Microbeads Made Of Magnetic Nanoparticles and Polymentioning

confidence: 99%

Recent Advances on Polymeric Beads or Hydrogels as Embolization Agents for Improved Transcatheter Arterial Chemoembolization (TACE)

et al. 2019

View full text Add to dashboard Cite

Transcatheter arterial chemoembolization (TACE), aiming to block the hepatic artery for inhibiting tumor blood supply, became a popular therapy for hepatocellular carcinoma (HCC) patients. Traditional TACE formulation of anticancer drug emulsion in ethiodized oil (i.e., Lipiodol ® ) and gelatin sponge (i.e., Gelfoam ® ) had drawbacks on patient tolerance and resulted in undesired systemic toxicity, which were both significantly improved by polymeric beads, microparticles, or hydrogels by taking advantage of the elegant design of biocompatible or biodegradable polymers, especially amphiphilic polymers or polymers with both hydrophilic and hydrophobic chains, which could self-assemble into proposed microspheres or hydrogels. In this review, we aimed to summarize recent advances on polymeric embolization beads or hydrogels as TACE agents, with emphasis on their material basis of polymer architectures, which are important but have not yet been comprehensively summarized.

show abstract

“…In short, 200 mg of PLGA were dissolved in dichlormethane as an organic solvent. MCNP were coated with C12-bisphosphonate to ensure a stable suspension in organic solvents [13] and added to the PLGA solution at a ratio of 1:5 (MCNP:PLGA). CPT was dissolved in dimethylsulfoxid at a ratio of 1:100 (CPT:PLGA) and added to the PLGA/MCNP suspension to form the organic phase.…”

Section: Preparation Of Microspheresmentioning

confidence: 99%

Biodegradable magnetic microspheres for drug targeting, temperature controlled drug release, and hyperthermia

Zahn

Weidner

Saatchi

et al. 2019

Current Directions in Biomedical Engineering

Self Cite

View full text Add to dashboard Cite

Magnetic microspheres (MMS) used for magnetic drug targeting consist of magnetic nanoparticles (MNP) and a pharmaceutical agent embedded in a polymeric matrix material. The application of MNP for drug targeting enables guiding the MMS to a target area, imaging the position of the MMS with magnetic particle imaging, and finally inducing drug release. As latter takes place by degradation of the MMS or diffusion through the matrix, an increase in temperature, e.g. through magnetic hyperthermia, leads to an accelerated drug release. Here, MMS consisting of poly(lactic-coglycolic) acid (PLGA) with different monomer ratios were prepared by an oil-in-water emulsion evaporation method. The model drug Camptothecin (CPT) and magnetic multicore nanoparticles (MCNP) with a high specific heating rate were embedded into the microspheres. We obtained MMS in the preferred size range of 1 to 2 μm with a concentration of MCNP of 16wt%, a drug load of about 0.5wt% and an excellent heating performance of 161 W/gMMS. Investigations of the drug release behaviour showed an accelerated drug release when increasing the temperature from 20 °C to 37 °C or 43 °C by using a water bath. In addition, an increase in drug release of about 50% through magnetic heating of the MMS up to 44 °C compared to 37 °C was observed. By this, a magnetic hyperthermia induced CPT release from PLGA MMS is demonstrated for the very first time.

show abstract

Development of a Coflowing Device for the Size-Controlled Preparation of Magnetic-Polymeric Microspheres as Embolization Agents in Magnetic Resonance Navigation Technology

Cited by 28 publications

References 46 publications

Selective embolization with magnetized microbeads using magnetic resonance navigation in a controlled‐flow liver model

Selective embolization with magnetized microbeads using magnetic resonance navigation in a controlled‐flow liver model

Recent Advances on Polymeric Beads or Hydrogels as Embolization Agents for Improved Transcatheter Arterial Chemoembolization (TACE)

Biodegradable magnetic microspheres for drug targeting, temperature controlled drug release, and hyperthermia

Contact Info

Product

Resources

About