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Improving intranasal delivery of neurological nanomedicine to the olfactory region using magnetophoretic guidance of microsphere carriers.

Xi J, Zhang Z, Si XA - Int J Nanomedicine (2015)

Bottom Line: It is crucial to developing new methods that can deliver drug particles more effectively to the olfactory region.The optimal particle size was found to be approximately 15 μm for effective magnetophoretic guidance while avoiding loss of particles to the walls in the anterior nose.A 64-fold-higher delivery of dosage was predicted in the magnetized nose compared to the control case, which did not have a magnetic field.

View Article: PubMed Central - PubMed

Affiliation: School of Engineering and Technology, Central Michigan University, Mount Pleasant, MI, USA.

ABSTRACT

Background: Although direct nose-to-brain drug delivery has multiple advantages, its application is limited by the extremely low delivery efficiency (<1%) to the olfactory region where drugs can enter the brain. It is crucial to developing new methods that can deliver drug particles more effectively to the olfactory region.

Materials and methods: We introduced a delivery method that used magnetophoresis to improve olfactory delivery efficiency. The performance of the proposed method was assessed numerically in an image-based human nose model. Influences of the magnet layout, magnet strength, drug-release position, and particle diameter on the olfactory dosage were examined.

Results and discussion: Results showed that particle diameter was a critical factor in controlling the motion of nasally inhaled ferromagnetic drug particles. The optimal particle size was found to be approximately 15 μm for effective magnetophoretic guidance while avoiding loss of particles to the walls in the anterior nose. Olfactory delivery efficiency was shown to be sensitive to the position and strength of magnets and the release position of drug particles. The results of this study showed that clinically significant olfactory doses (up to 45%) were feasible using the optimal combination of magnet layout, selective drug release, and microsphere-carrier diameter. A 64-fold-higher delivery of dosage was predicted in the magnetized nose compared to the control case, which did not have a magnetic field. However, the sensitivity of olfactory dosage to operating conditions and the unstable nature of magnetophoresis make controlled guidance of nasally inhaled aerosols still highly challenging.

No MeSH data available.


Comparison of surface depositions among various magnet layouts.Notes: (A) Layout A; (B) layout B; (C) layout C. The only difference between layouts B and C is that the latter has a smaller release area. The time evolution of olfactory deposition for the three magnet layouts is shown in (D). Red arrow indicate the nasal valve.Abbreviation: M, magnetization.
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f7-ijn-10-1211: Comparison of surface depositions among various magnet layouts.Notes: (A) Layout A; (B) layout B; (C) layout C. The only difference between layouts B and C is that the latter has a smaller release area. The time evolution of olfactory deposition for the three magnet layouts is shown in (D). Red arrow indicate the nasal valve.Abbreviation: M, magnetization.

Mentions: To identify the appropriate magnet strength for effective olfactory delivery, a variety of volume magnetizations were tested by progressively increasing magnetization from 1×106 A/m by an increment of 1×105 A/m. It was observed that after an increase in maximum magnetization to 7.1×107 A/m (detailed magnet strength listed in Figure 6B), about 33% of the administered particles reached and deposited in the olfactory region (Figures 6B and 7B). About 48% of the released particles deposited around the nasal valve, which should be avoided ideally.


Improving intranasal delivery of neurological nanomedicine to the olfactory region using magnetophoretic guidance of microsphere carriers.

Xi J, Zhang Z, Si XA - Int J Nanomedicine (2015)

Comparison of surface depositions among various magnet layouts.Notes: (A) Layout A; (B) layout B; (C) layout C. The only difference between layouts B and C is that the latter has a smaller release area. The time evolution of olfactory deposition for the three magnet layouts is shown in (D). Red arrow indicate the nasal valve.Abbreviation: M, magnetization.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4334328&req=5

f7-ijn-10-1211: Comparison of surface depositions among various magnet layouts.Notes: (A) Layout A; (B) layout B; (C) layout C. The only difference between layouts B and C is that the latter has a smaller release area. The time evolution of olfactory deposition for the three magnet layouts is shown in (D). Red arrow indicate the nasal valve.Abbreviation: M, magnetization.
Mentions: To identify the appropriate magnet strength for effective olfactory delivery, a variety of volume magnetizations were tested by progressively increasing magnetization from 1×106 A/m by an increment of 1×105 A/m. It was observed that after an increase in maximum magnetization to 7.1×107 A/m (detailed magnet strength listed in Figure 6B), about 33% of the administered particles reached and deposited in the olfactory region (Figures 6B and 7B). About 48% of the released particles deposited around the nasal valve, which should be avoided ideally.

Bottom Line: It is crucial to developing new methods that can deliver drug particles more effectively to the olfactory region.The optimal particle size was found to be approximately 15 μm for effective magnetophoretic guidance while avoiding loss of particles to the walls in the anterior nose.A 64-fold-higher delivery of dosage was predicted in the magnetized nose compared to the control case, which did not have a magnetic field.

View Article: PubMed Central - PubMed

Affiliation: School of Engineering and Technology, Central Michigan University, Mount Pleasant, MI, USA.

ABSTRACT

Background: Although direct nose-to-brain drug delivery has multiple advantages, its application is limited by the extremely low delivery efficiency (<1%) to the olfactory region where drugs can enter the brain. It is crucial to developing new methods that can deliver drug particles more effectively to the olfactory region.

Materials and methods: We introduced a delivery method that used magnetophoresis to improve olfactory delivery efficiency. The performance of the proposed method was assessed numerically in an image-based human nose model. Influences of the magnet layout, magnet strength, drug-release position, and particle diameter on the olfactory dosage were examined.

Results and discussion: Results showed that particle diameter was a critical factor in controlling the motion of nasally inhaled ferromagnetic drug particles. The optimal particle size was found to be approximately 15 μm for effective magnetophoretic guidance while avoiding loss of particles to the walls in the anterior nose. Olfactory delivery efficiency was shown to be sensitive to the position and strength of magnets and the release position of drug particles. The results of this study showed that clinically significant olfactory doses (up to 45%) were feasible using the optimal combination of magnet layout, selective drug release, and microsphere-carrier diameter. A 64-fold-higher delivery of dosage was predicted in the magnetized nose compared to the control case, which did not have a magnetic field. However, the sensitivity of olfactory dosage to operating conditions and the unstable nature of magnetophoresis make controlled guidance of nasally inhaled aerosols still highly challenging.

No MeSH data available.