Dextran coating is quite easy to perform. Please see the procedure in one of our publications (Bioconjugate Chemistry 2010, 21, 2128) for detailed procedures. The resulting dextran coated particles are colloidal stable without much precipitation over long period of time in saline. The dextran particles can then be functionalized with functional groups such as amine to attach targeting agents or drugs. Many groups include our own have used these particles for successful in vivo applications.

For other methods to functionalize the magnetic nanoparticles, you can refer to 

“Methods for Magnetic Nanoparticle Synthesis and Functionalization” in Chemistry of Bioconjugates: Synthesis, Characterization, and Biomedical Applications, Editor: Ravin Narain, John Wiley & Sons, 2014, pp281-314.

Please, contact Pr Etienne Duguet ICMCB [email protected]

Dextran coating is quite easy to perform. Please see the procedure in one of our publications (Bioconjugate Chemistry 2010, 21, 2128) for detailed procedures. The resulting dextran coated particles are colloidal stable without much precipitation over long period of time in saline. The dextran particles can then be functionalized with functional groups such as amine to attach targeting agents or drugs. Many groups include our own have used these particles for successful in vivo applications.

For other methods to functionalize the magnetic nanoparticles, you can refer to 

“Methods for Magnetic Nanoparticle Synthesis and Functionalization” in Chemistry of Bioconjugates: Synthesis, Characterization, and Biomedical Applications, Editor: Ravin Narain, John Wiley & Sons, 2014, pp281-314.

There is an easy way to coat iron oxide nano-particles with citric acid (not sure if you have considered it besides dextran) and I have read that citric acid coated nano-particles have been used in biological studies. Here is one of the references that discusses citric acid coating for iron oxide nano-particles (L. Li, K.Y. Mak, C.W. Leung, K.Y. Chan, W.K. Chan, W. Zhong, P.W.T. Pong, Effect of synthesis conditions on the properties of citric-acid coated iron oxide nanoparticles, Microelectronic Engineering, Volume 110, October 2013, Pages 329-334).

The preparation should be possible with nearly any modification (anion). But use the special properties of the material (that means magnetic sedimentation) in combination with dialysis. You may find a simple procedure within the attached publications.

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Thank Dear all for your answers.  Now I want to dissolve 24 mg of my particles in 0.15 ml of NaCl. If i took the desired mass and put it in the requested salt volume with adding the same mass of Dextran and sonicate the suspension for 30 min, do you think it will work ? 

Dear Samha, you can monitor the modification by performing step-by-step HATR-IR measurements similar to the measurements I have performed using ZnO.

Article Synthesis and testing of ZnO nanoparticles for photo-initiat...