@phdthesis{Feng2020, author = {Jun Feng}, title = {Printed soft optical waveguides for delivering light into deep tissue}, address = {Saarbr{\"u}cken}, doi = {10.22028/D291-31455}, url = {https://nbn-resolving.org/urn:nbn:de:bsz:291:415-2044}, pages = {VII, 149 S.}, year = {2020}, abstract = {To implement light-based diagnosis and therapies in the clinic, implantable patient-friendly devices that can deliver light inside the body while being compatible with soft tissues are needed. This Thesis presents the development of optical waveguides for guiding light into tissue, obtained by printing technologies from three different polymer combinations. Firstly, D,L-dithiothreitol (DTT) bridged PEG diacrylate were synthesized and printed into waveguides, which exhibited tunable mechanical properties and degradability, and low optical losses (as low as 0.1 dB cm-1 in visible range). Secondly, degradable waveguides from amorphous poly(D,L-lactide) and derived copolymers were developed by printing, which showed elasticity at body temperature and could guide VIS to NIR light in tissue for tens of centimeters. At last, soft and stretchable optical waveguides consisting of polydimethylsiloxane (PDMS) core and acrylated Pluronic F127 cladding were fabricated by coaxial extrusion printing, which could be stretched to 4 times of their length and showed optical loss values in tissue as low as 0.13 -0.34 dB cm-1 in the range of 405-520 nm. For proof-of-concept, above printed optical waveguides were used to deliver light across 5-8 cm tissue to remotely activate photochemical processes in in vitro cell cultures. The presented work exemplifies how rational study of medically approved biomaterials can lead to useful and cost-effective optical components for light applications.}, language = {en} }