الفهرس 
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Abstract
The trapping and manipulating of target cells and suspended particles from a medium is of great importance to cell biology, drug delivery, and related fields in biomedicine. Furthermore, the ability to trap and separate cells, which have tremendous medical applications, is of profound interest to the biomedical community.
In the present work, design and construct of a home-made trapping device to manipulate and separate cells were conducted using ultrasonic standing waves. The effect of various experimental conditions on trapping efficiency was conducted. The performance two ultrasonic trapping chamber (cylindrical and cuboidal ) at 0.8 MHz, different intensities ranged from 0.5-3 W/cm2 continuous wave ultrasound were investigated. Three different cell types (R.B.Cs, yeast and, E.coli) were used to investigate the cell size effect on trapping behavior. The effect of media concentration on trapping time and velocity of the cell was investigated.
Monitoring of the cells behavior during ultrasonic manipulation by using three simple techniques (light microscopy, dielectric measurement and optical absorption technique) was studied.
Light microscopy inspection reflects an instantaneous movement of the cells during trapping.
Dielectric measurement gives information about electrical properties of the cells.
Optical absorption measured the transmitted light passes through the trapping chamber.
The experimental results showed that:
Ultrasonic standing wave cell trapping and separation technique provides accurate, low power consumption with minimal damage to cells in addition to high throughput.
The device design is simple, and it is easy to design.
The trapping efficiency of cells increases with increasing ultrasound intensity.
Increasing the ultrasound intensity decreases the time consumed to trap cells.
The trapping force increases with increasing cell diameter.
There is no effect on cell membrane integrity exposed to ultrasonic standing wave.
Increasing of cell media concentration tends to increase the trapping time and decrease the cell velocity.
from the data of this work, it can be concluded that:
Acoustic standing waves provide an accurate, non-invasive, contactless, low power method of trapping that causes minimal damage to cells.
The acoustical trapping can potentially be applied to handle many cell types of different sizes.
Importance of the selection of ultrasound intensity at which the cell be trapped.
Importance of the selection of type, concentration and viscosity of the host media.
The success of our trapping technique would allow for more rapid advances in many other fields to take place such as:
a) Drug delivery
b) Cell encapsulation
c) Gene therapy
d) Biotechnology