title: Direct and sustained intracellular delivery of exogenous molecules using acoustic-transfection with high frequency ultrasound.
abstract: Controlling cell functions for research and therapeutic purposes may open new strategies for the treatment of many diseases. An efficient and safe introduction of membrane impermeable molecules into target cells will provide versatile means to modulate cell fate. We introduce a new transfection technique that utilizes high frequency ultrasound without any contrast agents such as microbubbles, bringing a single-cell level targeting and size-dependent intracellular delivery of macromolecules. The transfection apparatus consists of an ultrasonic transducer with the center frequency of over 150 MHz and an epi-fluorescence microscope, entitled acoustic-transfection system. Acoustic pulses, emitted from an ultrasonic transducer, perturb the lipid bilayer of the cell membrane of a targeted single-cell to induce intracellular delivery of exogenous molecules. Simultaneous live cell imaging using HeLa cells to investigate the intracellular concentration of Ca(2+) and propidium iodide (PI) and the delivery of 3 kDa dextran labeled with Alexa 488 were demonstrated. Cytosolic delivery of 3 kDa dextran induced via acoustic-transfection was manifested by diffused fluorescence throughout whole cells. Short-term (6 hr) cell viability test and long-term (40 hr) cell tracking confirmed that the proposed approach has low cell cytotoxicity.
authors: Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA.
authors: Sangpil
authors: S
authors: Yoon
authors: Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA.
authors: Min Gon
authors: MG
authors: Kim
authors: Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA.
authors: Chi Tat
authors: CT
authors: Chiu
authors: Department of Information and Communication Engineering, Daegu Gyeongbuk Institue of Science &Technology, Daegu, Korea.
authors: Jae Youn
authors: JY
authors: Hwang
authors: Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA.|Analogic Corporation, 8 Centennial Drive, Peabody, MA 01960, USA.
authors: Hyung Ham
authors: HH
authors: Kim
authors: Department of Bioengineering &Institute of Engineering in Medicine, University of California, San Diego, La Jolla, California 92093, USA.
authors: Yingxiao
authors: Y
authors: Wang
authors: Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA.
authors: K Kirk
authors: KK
authors: Shung
mesh_terms: D002118:Calcium / Q000378:metabolism; D002470:Cell Survival; D058948:Cell Tracking; D003911:Dextrans / Q000378:metabolism; D006367:HeLa Cells / Q000166:cytology*; D006801:Humans; D011419:Propidium / Q000378:metabolism; D014162:Transfection / Q000295:instrumentation / Q000379:methods*; D014463:Ultrasonography / Q000295:instrumentation* / Q000379:methods
chemical_list: D003911:Dextrans; D011419:Propidium; D002118:Calcium