Ali JAFFAL                                Version française               

Doctorant INSA

Bâtiment Blaise Pascal
7 avenue Jean Capelle
Tel : (33).

E-mail :

Localisation : 2

Research activities

Department :

Group : Spectroscopies et Nanomatériaux

Activities :

Publications (last 5 years)

Articles Conférences invitées Communications

Articles (3)

Determination of the spin orbit coupling and crystal field splitting in wurtzite InP by polarization resolved photoluminescence
N. Chauvin, A. Mavel, A. Jaffal, G. Patriarche, M. Gendry
Applied Physics Letters 112 071903 2018       
Shape-selective purification of gold nanorods with low aspect ratio using a simple centrifugation method
M. Boksebeld, N. Blanchard, A. Jaffal, Y. Chevolot, V. Monnier
Gold Bulletin 50 69-76 2017 AbstractThis work presents a new and simple procedure for the shape selective purification of gold nanorods from a mixture of rods and spheres. Previously reported methods were time-consuming and revealed several drawbacks such as low yields and difficulty to recover the purified nanoparticles. Additionally, they were mostly applied to high aspect ratio (AR) nanorods. Our process is based on only simple and short centrifugation steps in order to precipitate specifically gold nanospheres. Samples containing low AR nanorods (AR < 6) were selected to perform the purification process. The supernatant content was followed by UV-Visible absorption spectroscopy after each centrifugation step. Then, transmission electron microscopy (TEM) allowed extract the purification efficiency thanks to shape analyses performed on more than 1000 nanoparticles. These results showed that our centrifugation process was applied successfully to three sizes of nanorods (2.4, 3.7, and 5.3). High purification yields of 72 and 78% were attained for AR = 3.7 and AR = 5.3 nanorods, respectively.       
Folate-modified silicon carbide nanoparticles as multiphoton imaging nanoprobes for cancer-cell-specific labeling
M. Boksebeld, V. Kilin, A. Geloen, G. Ceccone, A. Jaffal, C. Schmidt, S. Alekseev, V. Lysenko, J. Wolf, L. Bonacina, E. Souteyrand, Y. Chevolot, V. Monnier
RCS Advances 7 27361-27369 2017 AbstractInterest in multiphoton microscopy for cell imaging has considerably increased over the last decade. Silicon carbide (SiC) nanoparticles exhibit strong second-harmonic generation (SHG) signal, and can thus be used as nonlinear optical probes for cell imaging. In this study, the surface of SiC nanoparticles was chemically modified to enable cancer-cell-specific labeling. In a first step, an aminosilane was grafted onto the surfaceof SiC nanoparticles. The resulting nanoparticles were further modified with folic acid, using an isothiocyanate-based coupling method. Nanoparticles from different functionalization steps were investigated by zeta potential measurement, colorimetric titration, infrared and ultraviolet-visible (UV-Vis) absorption spectroscopy, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Characterization results confirmed successful covalent grafting of silane and folic acid to nanoparticle surface. Finally, the efficacy of these folate-modified SiC nanoparticles for cancer-cell-specific labeling was evaluated by multiphoton microscopy, by measuring SHG-emitting cell area on multiphoton images. The average cancer-cell labeling percentage was about 48%, significantly higher than for negative controls (healthy cells, competition assay and poly(ethylene glycol) modified-SiC nanoparticles), where it ranged between 10% and 15%. These results demonstrated good efficiency and specificity for these folate-modified SiC nanoparticles in cancer-cell-specific labeling.       

Conférences invitées (0)

Communications (0)