Investigation of the size-effect in cobalt-ferrite nanoparticles using photoacoustic spectroscopy

Time-modulation of surface functionalization in biocompatible magnetic fluids

“…teristics [11] as well as information related to molecular species adsorbed on the nanoparticle shell [9]. As reported in the literature [10] while the photoacoustic features related to the hydroxyl group adsorbed onto the surface of transition metal-oxide nanoparticles appears at shorter wavelengths (band-S) other adsorbed functional groups (such as carboxyl, carbonyl, and amino) reveal photoacoustic features at longer wavelengths (band-L).…”

“…1. Band-C has been related to the absorption of the incident light by the core nanoparticle [11]. We emphasize that the PA signal scales with the optical absorption coefficient and, under low optical excitation intensities, the PA signal scales linearly with the optical absorption coefficient.…”

Use of the photoacoustic spectroscopy in the investigation of the dilution process in surface-coated nanoparticles

“…The light is chopped at a frequency of a few hertz, to improve the acoustic signal-to-noise ratio. Although photoacoustic spectroscopy (PAS) has been used as a material characterization technique for over three decades [22], PAS has been only recently used in the investigation of magnetic nanoparticles peptized as MFs [13][14][15][16]. Despite the simplicity of the PAS the experimental data taken from the MF samples had revealed important details concerning the core nanoparticle properties, the surface nanoparticle structure, and the nanoparticle coating layer characteristics [13][14][15][16].…”

“…Even more recently, photoacoustic spectroscopy has been introduced as a very promising characterization technique to investigate MF samples [13]. Despite the simplicity of the photoacoustic spectroscopy the experimental data taken from thin MF films deposited onto flat inert surfaces revealed important details regarding the core nanoparticle properties [14], the surface nanoparticle structure [15], and the nanoparticle coating layer characteristics [16]. In this study we used photoacoustic spectroscopy to investigate the effect of water dilution upon the surface molecular coating of maghemite nanoparticles peptized as biocompatible magnetic fluids.…”

Photoacoustic spectroscopy as a key technique in the investigation of nanosized magnetic particles for drug delivery systems

“…This paper is focused on the description of the basic characterization of nanosized magnetic particles used to produce a whole family of MDDS. Besides photoacoustic spectroscopy [1][2][3][4][5][6] other techniques used to characterize the MDDS include those related to the morphological/crystalline aspects [7][8][9][10][11][12], the magnetic and magneto-optical * Tel. : +55 61 3272 3151; fax: +55 61 3273 6655.…”