Hollow spherical nanoparticulate aggregates as potential ultrasound contrast agent: shell thickness characterization.
OBJECTIVE
The objective of this work is to manufacture hollow spherical nanoparticulate aggregates for use as an ultrasound contrast agent by means of spray drying of nanoparticulate suspension at a fast drying rate.


METHODS
Biocompatible PMMA-MeOPEGMA and silica nanoparticles are used as the model nanoparticles. The impacts of changing the nanoparticle concentration, pH, and spray drying operating condition on the size and shell thickness-to-particle radius (S/R) ratio, which governs the shell mechanical stability, are investigated.


CONCLUSIONS
The results indicate that the hollow microspheres size varies between 2 and 10 mum having S/R ratio between 2% and 4%, where the smaller size particles exhibit a higher S/R ratio. The resultant S/R ratio is found to be more influenced by process parameters acting at the nanoparticle scale (e.g., suspension pH) than by the spray drying operating condition.
Hadinoto
Kunn
K
School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore. kunnong@ntu.edu.sg
Cheow
Wean Sin
WS
D002626:Chemistry, Pharmaceutical / Q000379:methods; D003287:Contrast Media / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008689:Methacrylates / Q000737:chemistry; D053758:Nanoparticles; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D014463:Ultrasonography / Q000379:methods*
D003287:Contrast Media; D008689:Methacrylates; C456562:methoxy polyethylene glycol methacrylate; D011092:Polyethylene Glycols; D012822:Silicon Dioxide; D019904:Polymethyl Methacrylate