About Bio-Process Engineering Laboratory

The Bio-processing Engineering Laboratory organized by Prof. Hosokawa promotes developmental research on high-precision and fast manipulation methodologies for biological materials, such as cells and proteins, in which state-of-the-art laser technology is combined with microscopic manipulation and detection technologies. Especially we have the world’s top facilities and activities on cell manipulation and processing by femtosecond laser amplifier and have attracted attention as a pioneer of laser applications for biotechnology.

New insight technology applying femtosecond laser impulse

When an intense femtosecond laser is focused under microscope, the light energy concentrated both in space and in time. The highly condensed light induces micro-explosion at the laser focal point. By controlling pulse energy, pulse duration, and wavelength of the laser and optical condition in microscope, we can control the area of the explosion from minimum limitation of 1 ?m. When the explosion is induced in the vicinity of the micro-sized biological sample, shock and stress waves initiated by the explosion are acted to the sample as an impulsive force. In 2001, we have succeeded in detaching a single animal cell from the cultured substrate, which is impossible by optical tweezers because of the weak photon pressure. After that, we have promoted development of several kinds of methodologies to manipulate and to process several kinds of animal and plant cells with collaboration of biologist and medicine.

Elucidation of mechanics in biology

In the development, growth, and lesion of living-organisms, dynamics of structural change of cell and tissue is essential issue. The interaction between the dynamics and expression of the biological function has been attracted much attention in terms of “bio-mechanics” and “mechano-biology”. We have elucidated the interaction utilizing the femtosecond laser-induced impulsive force, which is the best controllable external force in time and space. We are also interested in large difference of the interaction between animal, plant and microorganism.

Adaptation of atomic force microscope and micro-fluidic chip

We have applied atomic force microscope (AFM) to quantification of the impulsive force. When the femtosecond laser-induced impulsive force is loaded on a probe (cantilever) mounted on the AFM, it induces a transient vibration of the cantilever. We developed new technology to quantify the impulsive force from the vibration. Furthermore, we are evaluating the stress tensor inside the micro-biological sample to analyze vibration of the sample induced by the impulsive force. On the other hand, the biggest problem of the sensing and processing under microscope is low efficiency of the throughput, although high-precision and flexible methods are realized combining the microscope with laser. One solution to overcome this problem is application of micro-fluidic chip. The femtosecond laser-induced impulsive force can be used as a “hand” in micro-channels in the chip. We have developed high-speed cell manipulation technique under microscope utilizing micro-fluidic chip.