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Updated: Jul 26, 2026
09:05
Generation and Quantitative Analysis of Pulsed Low Frequency Ultrasound to Determine the Sonic Sensitivity of Untreated and Treated Neoplastic Cells
Published on: July 22, 2015
Frequency dependence of sonophoresis
A Tezel1, A Sens, J Tuchscherer
1Department of Chemical Engineering, University of California Santa Barbara, California 93106, USA.
Pharmaceutical Research
|January 12, 2002
Summary
Low-frequency ultrasound enhances skin permeability for macromolecule delivery. Study findings reveal ultrasound frequency and intensity influence skin permeabilization, offering insights into low-frequency sonophoresis.
Area of Science:
- Biomedical Engineering
- Dermatology
- Acoustics
Background:
- Low-frequency ultrasound, or low-frequency sonophoresis, is a technique used to increase skin permeability.
- This facilitates the transdermal delivery of macromolecules.
Purpose of the Study:
- To investigate the relationship between low-frequency sonophoresis and ultrasound parameters.
- To determine the dependence of skin permeabilization on ultrasound frequency, intensity, and energy density.
Main Methods:
- Experiments were conducted using pig skin exposed to varying low-frequency ultrasound conditions.
- Skin permeabilization was quantified by measuring changes in electrical conductivity.
- Transport pathways induced by ultrasound were visualized through imaging.
Main Results:
- A threshold ultrasound intensity was identified for each frequency, below which no significant conductivity enhancement occurred.
- Higher frequencies required higher threshold intensities.
- While desired permeability could be achieved across frequencies, higher frequencies necessitated greater energy density.
- Low frequencies (around 20 kHz) resulted in localized transport, whereas higher frequencies (around 58.9 kHz) produced more dispersed effects.
Conclusions:
- This research provides a quantitative understanding of how low-frequency ultrasound affects skin permeability.
- The findings offer valuable data for optimizing low-frequency sonophoresis protocols for enhanced drug delivery.
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