Numerical Study On Transport Characteristics Of Multiple Magnetic Drug Particles Targeting In The Human Airways

Drug delivery technology is an important area of biomedicine.Compared with traditional inhalation therapy,magnetic drug targeting(MDT)therapy has brought new directions to respiratory diseases.MDT technology uses an external magnetic field to guide the movement of magnetic drug particles to the target area to maximize the drug concentration in the target area and reduce side effects on other parts.We reconstructed a real human respiratory tract model and uses LES and DPM to track and simulate magnetic drug particles with a particle size of 0.5μm-3μm.In addition,the effects of the five variables of magnetic source number,magnetic source position,respiration intensity,magnetic number and particle size on the deposition efficiency of the target area(left bronchus)were studied.The results of non-magnetic field inhalation therapy show that: due to the contraction structure of the throat,the maximum velocity of air flow always appears in the narrowest part of the larynx,and the jet and backflow during inhalation and exhalation appear in the upper trachea and mouth,respectively.For single magnetic source,choose Mn = 1T,the magnetic source at position 3 and the breathing intensity of 30 L / min are conducive to improving the deposition efficiency of 2μm particles in the target area.The conclusion of the multi-magnetic source is highly consistent with the former.When the magnetic source is located at position 2 and position 3,and the Mn is 0.75 T and the respiration intensity is 30 L / min,the deposition efficiency of the2μm particles in the target area is the highest five times the result without a magnetic field.In addition,when the sum of the Mn of the single magnetic source and the multiple magnetic source is the same,the total deposition of all particles in the left bronchus under the condition of the multiple magnetic source is basically higher than that of the single magnetic source.The larger the sum of Mn,the more the multimagnetic source is conducive to the deposition of large-diameter particles in the target area,and the effect on the upper respiratory tract is also smaller.In general,MDT technology has great application prospects in enhancing targeted deposition of drugs.