Maldiney T.,Unite de Pharmacologie Chimique et Genetique et dImagerie |
Sraiki G.,Chimie Paristech |
Viana B.,Chimie Paristech |
Gourier D.,Chimie Paristech |
And 6 more authors.
Optical Materials Express | Year: 2012
Ca2Si5N8:Eu2+, Tm3+ presents outstanding long lasting luminescence at about 610 nm. However, to be useful for in vivo optical imaging, persistent luminescence materials should possess high optical performance combined with sizes in the nanoscale. With this aim, we investigated two different techniques for the preparation of nanoparticles from Ca2Si5N8:Eu2+, Tm3+ bulk powder. First, nanoparticles were successfully prepared with the pulsed laser ablation method in liquid (abbreviated as PLAL). Secondly, nanoparticles obtained by selective sedimentation from the bulk compound resulted in satisfactory yield and allowed to perform the first real-time in vivo imaging with Ca2Si5N8:Eu2+, Tm3+ host. Finally the influence of surface functionalization on the biodistribution of the probe after systemic injection is discussed. ©2012 Optical Society of America.
Silva A.K.A.,Unite de Pharmacologie Chimique et Genetique et dImagerie |
Richard C.,Unite de Pharmacologie Chimique et Genetique et dImagerie |
Ducouret G.,University Pierre and Marie Curie |
Bessodes M.,Unite de Pharmacologie Chimique et Genetique et dImagerie |
And 2 more authors.
Biomacromolecules | Year: 2013
By taking advantage of a natural and abundant polymer as well as a straightforward film formation technique, this paper focuses on the conception and use of a new alternative tool for thermocontrolled cell detachment. Thermoresponsive xyloglucan was produced after partial galactose removal by a 24 h reaction with β-galactosidase. The obtained polymer (T24) was then activated by reaction with 4-nitrophenyl chloroformate (NPC) in order to graft a cyclic peptide presenting an arginine-glycine-aspartic acid (RGD) motif. The effect of RGD grafting on the sol-gel transition temperature of T24 is evaluated by rheological measurements. Solvent-casted films of T24-RGD successfully promoted cell adhesion, proliferation, and thermocontrolled detachment. The presented approach is a new alternative for cells sensitive to the proteolytic treatment routinely used for cell detachment. Because the RGD sequence used herein is widely recognized by different cell types, this protocol may be extended to other cells. Besides, the presented chemical route can be applied to different peptide sequences. © 2012 American Chemical Society.