Lasers create biomimetic scaffolds for growing cells
July 14, 2011
Research scientists at the Fraunhofer Institute for Laser Technology ILT have succeeded in producing hybrid biomimetic matrices that can serve as a basis for scaffold and implant structures on which cells can grow effectively.
The researchers developed a process for producing biomimetic scaffolds that closely emulate endogenous (within the body) tissue. This process allows the fabrication of specialized model systems for the study of 3-D cell growth.
The scientists used dissolved proteins and polymers that were irradiated with laser light and cross-linked by photolytic processes. They deployed specially developed laser systems that — by means of ultra-short laser
pulses — triggered multiphoton processes that led to polymerization.
The key factors in the process were the extremely short pulse durations and the high laser-beam intensities. The short pulse duration led to almost no damage by heat to the material. Ultra-fast pulses in the megawatt range drove a massive amount of protons into the laser focus in an extremely short time, triggering a non-linear effect.
The molecules in the liquid absorbed several photons simultaneously, causing free radicals to form that triggered a chemical reaction between the surrounding molecules.
As a result of this process of multiphoton polymerization, solids formed from the liquid. Using CAD data, a computer controlled the position of the laser beam through a microscope with a precision of a few hundred nanometers, in such a way that micrometer-fine, stable volume elements of cross-linked material gradually formed.
The researchers were able to produce cell scaffolds with a resolution of approximately one micrometer from dissolved proteins and polymers.
The long-term aim is to also use the process to produce complete artificial tailor-made organs, the researchers said.