Title
Sculpting the internal architecture of fluorescent silica particles via a template-free approach
Document Type
Article
Publication Date
4-1-2016
Abstract
Particles with an open, porous structure can be used to deliver payloads. It is often of interest to detect such particles in tissue or materials, which is facilitated by addition of dye. A straightforward approach leading to fluorescent, porous silica particles is described. The particles are etched with 3mM aqueous sodium hydroxide, taking advantage of the etching rate difference between normal silica and an interior band of silica that contains covalently attached dye. No additional steps, such as dye labeling or thermal annealing, are required. Etching modeled the internal structure of the fluorescent silica particles by creating meso/macropores and voids, as reflected by nitrogen absorption measurements. In order to investigate whether a polymer shell influences etching, certain composite particles are top-coated with poly(l-lysine) representing neutral or positive charged surfaces under typical pH conditions in living systems. The polypeptide-coated fluorescent silica cores exhibit the same porous morphology as uncoated homologs. The polypeptide topcoat does little to alter the permeation by the etching agent. Preservation of size during etching, confirmed by dynamic light scattering, transmission electron microscopy and small-angle X-ray scattering, simplifies the use of these template-free porous fluorescent particles as platforms for drug encapsulation, drug carriers and in vivo imaging.
Publication Source (Journal or Book title)
Journal of colloid and interface science
First Page
321
Last Page
334
Recommended Citation
Rosu, C., Gorman, A. J., Cueto, R., Dooley, K. M., & Russo, P. S. (2016). Sculpting the internal architecture of fluorescent silica particles via a template-free approach. Journal of colloid and interface science, 467, 321-334. https://doi.org/10.1016/j.jcis.2016.01.007