title: Super-sensitivity in label-free protein sensing using a nanoslot nanolaser.
abstract: Microphotonic sensors have been actively studied with increasing demands for label-free biosensing in medical diagnoses and life sciences. For high-throughput and low-cost sensing, a high sensitivity is crucial for eliminating the pre-concentration process, while a simple setup of sensors is also desirable. This paper demonstrates a super-sensitivity for protein, which satisfies these requirements. The key device is a photonic crystal nanolaser, in particular with a nanoslot. Even using a simple setup, the nanolaser achieves an extraordinary-low detection limit for BSA protein, i.e. 255 fM on an average, which cannot be explained by its bulk index sensitivity. The specific adsorption of the protein is observed only around the nanoslot with strong laser intensity. This suggests that the super-sensitivity arises from the effective trapping of protein in the nanoslot.
authors.affiliation: Department of Electrical and Computer Engineering, Yokohama National University, Hodogayaku, Yokohama, Japan. 5d09sd103@ynu.ac.jp
authors.forename: Shota
authors.initials: S
authors.lastname: Kita
authors.forename: Shoji
authors.initials: S
authors.lastname: Hachuda
authors.forename: Shota
authors.initials: S
authors.lastname: Otsuka
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Endo
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Imai
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nishijima
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Misawa
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Baba
mesh_terms: D000327:Adsorption; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000706:statistics & numerical data; D002417:Cattle; D004867:Equipment Design; D053844:Lasers, Solid-State; D055620:Optical Phenomena; D011506:Proteins / Q000032:analysis*; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000032:analysis; D020349:Surface Plasmon Resonance; D014159:Transducers
chemical_list: D011506:Proteins; D012710:Serum Albumin, Bovine