CHARACTERISTICS AND EFFICACY OF ULTRAFAST LASER PULSES FOR BIOMEDICAL APPLICATIONS

For the fabrication of three dimensional cell scaffolds, femtosecond laser irradiation at 800nm was used for biomedical applications. The femtosecond laser system was also used to fabricate a bricks and mortar structure in keratin films to investigate skin structures for different cream absorption. The laser characterised here is Spectra Physics, Hurricane X.  This is a complex laser system consisting of a seed laser and a regenerative amplifier.  It is important to have knowledge of these characteristics to be able to predict the transport of the beam through various optical elements and also to analyse the subsequent interaction with materials. The whole optical intensity profile in two dimensional space of a laser beam i.e. across the beam radius and its detailed shape has been measured and i t has been demonstrated that Ti: sapphire laser system has the ability to fabricate three dimensional structures for biomedical applications. Tissue scaffolds have been prepared with different pore sizes suitable for application in different living tissues. Polymerisation based on a direct write system to build up solid polymeric material for the fabrication of three dimensional cell scaffolds can be achieved. By tailoring the optical system and making use of a relatively weak absorption cross-section we have been able to manufacture deep structures in a single pass of the laser light.