title: Non-contact microdrilling of mouse zona pellucida with an objective-delivered 1.48-microns diode laser.
abstract: OBJECTIVE
  A non-touch laser-induced microdrilling procedure is studied on mouse zona pellucida (ZP).
  
  
  METHODS
  A 1.48-microns diode laser beam is focused in a 8-microns spot through a 45x objective of an inverted microscope. Mouse zygotes, suspended in a culture medium, are microdrilled by exposing their ZP to a short laser irradiation and allowed to develop in vitro.
  
  
  RESULTS
  Various sharp-edged holes can be generated in the ZP with a single laser irradiation. Sizes can be varied by changing irradiation time (3-100 ms) or laser power (22-55 mW). Drilled zygotes present no signs of thermal damage under light and scanning electron microscopy and develop as expected in vitro, except for a distinct eight-shaped hatching behavior.
  
  
  CONCLUSIONS
  The microdrilling procedure can generate standardized holes in mouse ZP, without any visible side effects. The hole formation can be explained by a local photothermolysis of the protein matrix.
authors.affiliation: Laboratoire d'Optique Appliquée, Ecole Polytechnique Fédérale de Lausanne, Switzerland.
authors.forename: K
authors.initials: K
authors.lastname: Rink
authors.forename: G
authors.initials: G
authors.lastname: Delacrétaz
authors.forename: R P
authors.initials: RP
authors.lastname: Salathé
authors.forename: A
authors.initials: A
authors.lastname: Senn
authors.forename: D
authors.initials: D
authors.lastname: Nocera
authors.forename: M
authors.initials: M
authors.lastname: Germond
authors.forename: P
authors.initials: P
authors.lastname: De Grandi
authors.forename: S
authors.initials: S
authors.lastname: Fakan
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000648:ultrastructure; D003470:Culture Media; D046508:Culture Techniques; D016326:Extracellular Matrix Proteins / Q000648:ultrastructure; D006358:Hot Temperature; D053685:Laser Therapy / Q000295:instrumentation*; D007834:Lasers; D007909:Lenses; D051379:Mice; D008815:Mice, Inbred Strains; D008853:Microscopy / Q000295:instrumentation; D008855:Microscopy, Electron, Scanning; D008866:Microsurgery / Q000295:instrumentation*; D015044:Zona Pellucida / Q000648:ultrastructure*; D015053:Zygote / Q000648:ultrastructure
chemical_list: D003470:Culture Media; D016326:Extracellular Matrix Proteins