title: Optical super-resolution imaging by high-index microspheres embedded in elastomers.
abstract: We demonstrated feasibility of super-resolution imaging through high-index microspheres embedded in transparent elastomers. We performed imaging, with resolution improvement by a factor of two, by using implanted barium titanate glass microspheres (diameters ∼30-150  μm and refractive index ∼1.9-2.1) in a thin film of polydimethylsiloxane elastomer placed over the specimen. Microsphere-assisted imaging technique is a promising candidate for applications in cancer research. As a proof-of-principle, we used microsphere-assisted imaging technique for the observation of radiation-induced γ-H2AX foci formation in U87 human glioblastoma cells irradiated by clinical proton beams.
authors.forename: Arash
authors.initials: A
authors.lastname: Darafsheh
authors.forename: Consuelo
authors.initials: C
authors.lastname: Guardiola
authors.forename: Averie
authors.initials: A
authors.lastname: Palovcak
authors.forename: Jarod C
authors.initials: JC
authors.lastname: Finlay
authors.forename: Alejandro
authors.initials: A
authors.lastname: Cárabe
mesh_terms: D017609:Barium Compounds / Q000737:chemistry; D045744:Cell Line, Tumor; D020724:Elastomers / Q000737:chemistry*; D005240:Feasibility Studies; D006801:Humans; D008863:Microspheres; D061848:Optical Imaging / Q000379:methods*; D055620:Optical Phenomena; D014025:Titanium / Q000737:chemistry
chemical_list: D017609:Barium Compounds; D020724:Elastomers; C024547:barium titanate(IV); D014025:Titanium