title: Implantable semiconductor biosensor for continuous in vivo sensing of far-red fluorescent molecules.
abstract: We have fabricated miniature implantable fluorescence sensors for continuous fluorescence sensing applications in living subjects. These monolithically integrated GaAs-based sensors incorporate a 675 nm vertical-cavity surface-emitting laser (VCSEL), a GaAs PIN photodiode, and a fluorescence emission filter. We demonstrate high detection sensitivity for Cy5.5 far-red dye (50 nanoMolar) in living tissue, limited by the intrinsic background autofluorescence. These low cost, sensitive and scalable sensors are promising for long-term continuous monitoring of molecular dynamics for biomedical studies in freely moving animals.
authors.affiliation: Department of Electrical Engineering, Stanford University, 420 via Palou, Stanford, CA 94305-4075, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: O'Sullivan
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Munro
authors.forename: Natesh
authors.initials: N
authors.lastname: Parashurama
authors.forename: Christopher
authors.initials: C
authors.lastname: Conca
authors.forename: Sanjiv S
authors.initials: SS
authors.lastname: Gambhir
authors.forename: James S
authors.initials: JS
authors.lastname: Harris
authors.forename: Ofer
authors.initials: O
authors.lastname: Levi
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D002232:Carbocyanines / Q000378:metabolism; D005453:Fluorescence; D007834:Lasers; D051379:Mice; D008819:Mice, Nude; D019736:Prostheses and Implants; D012666:Semiconductors / Q000295:instrumentation*; D013050:Spectrometry, Fluorescence; D013499:Surface Properties
chemical_list: C098793:CY5.5 cyanine dye; D002232:Carbocyanines