title: Detection of a few metallo-protein molecules using color centers in nanodiamonds.
abstract: Nanometer-sized diamonds containing nitrogen-vacancy defect centers (NV) are promising nanosensors in biological environments due to their biocompatibility, bright fluorescence, and high magnetic sensitivity at ambient conditions. Here we report on the detection of ferritin molecules using magnetic noise induced by the inner paramagnetic iron as a contrast mechanism. We observe a significant reduction of both coherence and relaxation time due to the presence of ferritin on the surface of nanodiamonds. Our theoretical model is in excellent agreement with the experimental data and establishes this method as a novel sensing technology for proteins.
authors.affiliation: Institut für Quantenoptik and IQST, ‡Institut für Organische Chemie III and IQST, §Institut für Theoretische Physik and IQST, and ∥Materialwissenschaftliche Elektronenmikroskopie and IQST, Albert-Einstein Allee 11, Universität Ulm , 89069 Ulm, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Ermakova
authors.forename: G
authors.initials: G
authors.lastname: Pramanik
authors.forename: J-M
authors.initials: JM
authors.lastname: Cai
authors.forename: G
authors.initials: G
authors.lastname: Algara-Siller
authors.forename: U
authors.initials: U
authors.lastname: Kaiser
authors.forename: T
authors.initials: T
authors.lastname: Weil
authors.forename: Y-K
authors.initials: YK
authors.lastname: Tzeng
authors.forename: H C
authors.initials: HC
authors.lastname: Chang
authors.forename: L P
authors.initials: LP
authors.lastname: McGuinness
authors.forename: M B
authors.initials: MB
authors.lastname: Plenio
authors.forename: B
authors.initials: B
authors.lastname: Naydenov
authors.forename: F
authors.initials: F
authors.lastname: Jelezko
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003124:Colorimetry / Q000295:instrumentation*; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008667:Metalloproteins / Q000032:analysis* / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D040081:Protein Array Analysis / Q000295:instrumentation*
chemical_list: D008667:Metalloproteins