Towards clinical use of a laser-induced microjet system aimed at reliable and safe drug delivery.
An Er:YAG laser with 2940-nm wavelength and 250-μs pulse duration is used to generate a microjet that is ejected at ∼50 m/s in air. The strength of the microjet depends on the bubble dynamics from the beam-water interaction within the driving chamber as well as the discharging of the drug solution underneath the elastic membrane that separates the drug from the driving liquid. The jet characteristics, such as velocity, volume, and level of atomization, are obtained by high-speed camera images taken at 42,000 fps. The enhancements in jet volume (dosage) and repeated jet generation, which are aimed at making the injector suitable for general clinical applications, are achieved. The generation of repeated microjets is achieved with the help of a stepping motor that provides a uniform pressure within the drug reservoir before an ejection occurs through a micro nozzle. Also, two types of human growth hormones are used for monitoring any potential thermal damage to the drug solution due to a repeated laser ablation when driving the microjet. We provide strong evidence to support that the drugs, as they are injected to porcine skins, are free of the damage associated with the present delivery method.
Seoul National University, Department of Mechanical and Aerospace Engineering, Seoul 151-742, Republic of Korea.
Hun-jae
HJ
Jang
Seoul National University, Department of Mechanical and Aerospace Engineering, Seoul 151-742, Republic of Korea.
Hyeonju
H
Yu
B & B Systems, 481-10 Gasan-Dong, Geumcheon-Gu, Seoul 153-803, Republic of Korea.
Seonggeun
S
Lee
LG Household & Health Care R & D Center, 84 Jang-dong, Yuseong-gu, Daejeon 305-343, Republic of Korea.
Eugene
E
Hur
LG Household & Health Care R & D Center, 84 Jang-dong, Yuseong-gu, Daejeon 305-343, Republic of Korea.
Yoonkwan
Y
Kim
LG Household & Health Care R & D Center, 84 Jang-dong, Yuseong-gu, Daejeon 305-343, Republic of Korea.
Seol-Hoon
SH
Lee
LG Household & Health Care R & D Center, 84 Jang-dong, Yuseong-gu, Daejeon 305-343, Republic of Korea.
Naegyu
N
Kang
Seoul National University, Department of Mechanical and Aerospace Engineering, Seoul 151-742, Republic of Korea.
Jack J
JJ
Yoh
D016503:Drug Delivery Systems / Q000295:instrumentation* / Q000379:methods*; D004815:Epidermal Growth Factor; D019382:Human Growth Hormone; D006801:Humans; D053844:Lasers, Solid-State; D055616:Microtechnology / Q000295:instrumentation*
D019382:Human Growth Hormone; D004815:Epidermal Growth Factor