Sep 20 2012
Researchers from the Faculty of Science and Technology at the University of the Basque Country (UPV/EHU), in collaboration with scientists from the Consejo Superior de Investigaciones Científicas (CSIC) and the Universidad Complutense de Madrid have developed a new laser material which improves the use of light in biophotonics, making it more efficient and longer lasting by incorporating dye molecules.
Image of the recreation of the FRET process
The development, published in Nature Photonics magazine, has applications in fields as diverse as medicine, agriculture and environmental sciences.
Scientists have obtained efficient long lasting emissions of red laser light for the first time thanks to the incorporation of two dye molecules which are confined in latex nanoparticles dispersed in water. The wavelength of red light is key in photodynamic therapy, with uses in ophthalmology and dermatology, for example.
Until now, the use of commercial colorants for these applications were limited by the little excitation light they absorbed, an inconvenience which reduced its efficiency. On the other hand, the colorants are normally damaged with ease when excited, reducing its technological use and increases the cost.
To solve these problems the scientists decided to resort to an energy transfer process known as Förster Resonance Energy Transfer (FRET) based on incorporating two dyes: one donor, capable of efficiently absorbing the excitation and which is hardly damaged, and another acceptor which emits light after having received the energy from the first.
Researchers emphasize that this new material laser eliminates the need to use large volumes of organic solvents, the majority of which are toxic and carcinogenic, avoiding the generation of waste which is harmful to health and the environment.