title: Miniature probe for the delivery and monitoring of a photopolymerizable material.
abstract: Photopolymerization is a common method to cure materials initially in a liquid state, such as dental implants or bone or tissue fillers. Recent advances in the development of biocompatible gel- and cement-systems open up an avenue for in situ photopolymerization. For minimally invasive surgery, such procedures require miniaturized surgical endoscopic probes to activate and control photopolymerization in situ. We present a miniaturized light probe in which a photoactive material can be (1) mixed, pressurized, and injected, (2) photopolymerized/photoactivated, and (3) monitored during the chemical reaction. The device is used to implant and cure poly(ethylene glycol) dimethacrylate-hydrogel-precursor in situ with ultraviolet A (UVA) light (365 nm) while the polymerization reaction is monitored in real time by collecting the fluorescence and Raman signals generated by the 532-nm excitation light source. Hydrogels could be delivered, photopolymerized, and monitored by the probe up to a curing depth of 4 cm. The size of the photopolymerized samples could be correlated to the fluorescent signal collected by the probe, and the reproducibility of the procedure could be demonstrated. The position of the probe tip inside a bovine caudal intervertebral disc could be estimated in vitro based on the collected fluorescence and Raman signal.
authors.affiliation: Swiss Federal Institute of Technology Lausanne, Microengineering Institute, Laboratory of Applied Photonics Devices, Station 17, Lausanne 1015, SwitzerlandbSwiss Federal Institute of Technology Lausanne, Institute of Bioengineering, Laboratory of Biomecha.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schmocker
authors.affiliation: Swiss Federal Institute of Technology Lausanne, Institute of Bioengineering, Laboratory of Biomechanical Orthopedics, Station 19, Lausanne 1015, SwitzerlandcSwiss Federal Institute of Technology Lausanne, Institute of Materials, Laboratory of Polymer and.
authors.forename: Azadeh
authors.initials: A
authors.lastname: Khoushabi
authors.affiliation: Clinic Cecil, Neuro-orthopedic Spine Unit, Avenue Louis-Ruchonnet 53, Lausanne 1003, Switzerland.
authors.forename: Constantin
authors.initials: C
authors.lastname: Schizas
authors.affiliation: Swiss Federal Institute of Technology Lausanne, Institute of Materials, Laboratory of Polymer and Composite Technology, Station 12, Lausanne 1015, Switzerland.
authors.forename: Pierre-Etienne
authors.initials: PE
authors.lastname: Bourban
authors.affiliation: Swiss Federal Institute of Technology Lausanne, Institute of Bioengineering, Laboratory of Biomechanical Orthopedics, Station 19, Lausanne 1015, Switzerland.
authors.forename: Dominique P
authors.initials: DP
authors.lastname: Pioletti
authors.affiliation: Swiss Federal Institute of Technology Lausanne, Microengineering Institute, Laboratory of Applied Photonics Devices, Station 17, Lausanne 1015, Switzerland.
authors.forename: Christophe
authors.initials: C
authors.lastname: Moser
mesh_terms: D000818:Animals; D016880:Anisotropy; D001672:Biocompatible Materials / Q000737:chemistry*; D018786:Bone Substitutes; D002417:Cattle; D003432:Cross-Linking Reagents / Q000737:chemistry; D015921:Dental Implants; D016503:Drug Delivery Systems; D020100:Hydrogels / Q000737:chemistry; D007403:Intervertebral Disc; D008027:Light; D008689:Methacrylates / Q000737:chemistry; D008856:Microscopy, Fluorescence; D055668:Photochemical Processes; D010777:Photochemistry / Q000379:methods; D011092:Polyethylene Glycols / Q000737:chemistry; D058105:Polymerization; D011108:Polymers / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D014466:Ultraviolet Rays
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D003432:Cross-Linking Reagents; D015921:Dental Implants; D020100:Hydrogels; D008689:Methacrylates; D011108:Polymers; C421283:poly(ethylene glycol)-dimethacrylate; D011092:Polyethylene Glycols