title: Photoacoustic effect measurement in aqueous suspensions of gold nanorods caused by low-frequency and low-power near-infrared pulsing laser irradiation.
abstract: When aqueous suspensions of gold nanorods are irradiated with a pulsing laser (808 nm), pressure waves appear even at low frequencies (pulse repetition rate of 25 kHz). We found that the pressure wave amplitude depends on the dynamics of the phenomenon. For fixed concentration and average laser current intensity, the amplitude of the pressure waves shows a trend of increasing with the pulse slope and the pulse maximum amplitude. We postulate that the detected ultrasonic pressure waves are a sort of shock waves that would be generated at the beginning of each pulse, because the pressure wave amplitude would be the result of the positive interference of all the individual shock waves.
authors.affiliation: Centre for Biomedical Technology (CTB), Universidad Politécnica de Madrid (UPM), Campus de Montegancedo, 28223, Pozuelo de Alarcón, Madrid, Spain. cristina.sanchez@ctb.upm.es
authors.forename: Cristina Sánchez
authors.initials: CS
authors.lastname: López de Pablo
authors.forename: Julio Alberto
authors.initials: JA
authors.lastname: Ramos Ávila
authors.forename: Tamara
authors.initials: T
authors.lastname: Fernández Cabada
authors.forename: Francisco
authors.initials: F
authors.lastname: del Pozo Guerrero
authors.forename: José Javier
authors.initials: JJ
authors.lastname: Serrano Olmedo
mesh_terms: D000162:Acoustics; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000528:radiation effects; D004867:Equipment Design; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007834:Lasers; D008027:Light; D028022:Low-Level Light Therapy; D053768:Metal Nanoparticles / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry*; D011312:Pressure; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D014465:Ultrasonics
chemical_list: D006046:Gold