Sylvain Clede

• Ecole Normale Supérieure de Paris

IntroductionInterphasic DNA has a constant three-dimensional conformation, which is particularly striking for spermatic DNA, with distinct chromosomal territories and a constant chromosomal conformation. We hypothesized that this organization is fragile, and that an excess or a lack of chromosomal segments could hinder the genomic structure as a wh...

Presented here is the exploitation of synchrotron infrared spectromicroscopy to evaluate the feasibility of monitoring the cellular uptake of rhenium-tris-carbonyl-tagged (Re(CO) 3 ) lipophilic chains in living cells. To this aim, an in-house thermostated microfluidic device was used to limit water absorption while keeping cells alive. Indeed, cell...

This study evaluates the penetration of bicosome systems incorporating two different antioxidants into normal skin and skin exposed to ultraviolet-visible radiation (UV-VIS) by Fourier-transform infrared microspectroscopy (FT-IR) using synchrotron radiation. Bicosomes are phospholipid assemblies based on mixtures of discoidal lipid structures prote...

An organometallic derivative of praziquantel was studied directly in worms, using ICP-MS for quantification and synchrotron based imaging. X-Ray fluorescence and IR absorption microspectroscopy, were used for the first time in combination to directly locate this organometallic drug candidate in schistosomes. The detection of both CO (IR) and Cr (XR...

From metal carbonyls to single core multimodal probes for imaging Metal carbonyls are ideal candidates for bimodal bio-imaging due to their appropriate vibrational and luminescence properties. The main focus of this work has been the development, the study and the use of a rhenium tris-carbonyl unit [LRe(CO)3X] (L = pyridyl-1,2,3-triazole, X = Cl-)...

A rhenium tris-carbonyl derivative (fac-[Re(CO)3Cl(2-(1-dodecyl-1H-1,2,3,triazol-4-yl)-pyridine)]) was incorporated into phospholipid assemblies, called bicosomes, and the penetration of this molecule into skin was monitored using Fourier-transform infrared microspectroscopy (FTIR). To evaluate the capacity of bicosomes to promote the penetration o...

A correlative approach combining synchrotron radiation based IR microscopy and fluorescence microscopy enabled the successful detection and quantification of a nona-arginine peptide labelled with a Single Core Multimodal Probe for Imaging (SCoMPI) in skin biopsies. The topical penetration of the conjugate appeared to be time dependent and occurred...

While chromosomal translocations are usually associated with a normal phenotype, they can still cause male infertility as well as recurrent miscarriages and fetal malformations related to their transmission in an unbalanced state. The distinction between balanced and unbalanced spermatozoa on morphological criteria is still unfeasible. However, we...

Metal–carbonyl complexes are attractive structures for bio-imaging. In addition to unique vibrational properties due to the CO moieties enabling IR and Raman cell imaging, the appropriate choice of ancillary ligands opens up the opportunity for luminescence detection. Through a classification by techniques, past and recent developments in the appli...

Rhenium triscarbonyl complexes fac-[Re(CO)3 (N^N)] with appropriate ancillary N^N ligands are relevant for fluorescent bio-imaging. Recently, we have shown that [Re(CO)3 ] cores can also be efficiently mapped inside cells using their IR signature and that they can thus be used in a bimodal approach. To describe them we have coined the term SCoMPIs...

Re(I) tricarbonyl complexes are of considerable interest as bioimaging probes. Single-core multimodal probes for imaging (SCoMPIs) display unique photophysical properties enabling their unequivocal detection in cells. New SCoMPIs were prepared from an ancillary 1-(2-pyridyl)-1,2,3-triazole ligand, denoted Tapy, a regioisomer of the widely used Pyta...

3-Methoxy-17α-ethynylestradiol or mestranol is a prodrug for ethynylestradiol and the estrogen component of some oral contraceptive formulations. We demonstrate here that a single core multimodal probe for imaging - SCoMPI - can be efficiently grafted onto mestranol allowing its tracking in two breast cancer cell lines, MDA-MB-231 and MCF-7 fixed c...

Advancements in widefield infrared spectromicroscopy have recently been demonstrated following the commissioning of IRENI (InfraRed ENvironmental Imaging), a Fourier Transform infrared (FTIR) chemical imaging beamline at the Synchrotron Radiation Center. The present study demonstrates the effects of magnification, spatial oversampling, spectral pre...

Biomolecules display specific vibrational signatures in the infrared (IR) range, and organelles that concentrate these biomolecules can be identified by these IR signatures. Subcellular identification and location of cell organelles using IR signatures is attractive as it does not require the use of any specific trackers and is thus non-invasive an...

A rhenium tris-carbonyl derivative has been designed to couple infrared and luminescent detection in cells. Both spectroscopies are consistent with one another; they point out the reliability of the present SCoMPI (for Single Core Multimodal Probe for Imaging) for bimodal imaging and unambiguously indicate a localization at the Golgi apparatus in M...

1,1-Di(4-hydroxyphenyl)-2-cyrhetrenylbut-1-ene 1 is an organometallic conjugate where a [(Cp)Re(CO)(3)] unit is linked to a hydroxytamoxifen-like structure. Its subcellular nuclear distribution was previously observed in a single cell using the near-field technique AFMIR. We show here that synchrotron radiation FTIR spectromicroscopy (SR-FTIR-SM) e...

Some like it hot! The photothermally induced resonance technique, in which an AFM microscope is coupled to a tunable pulsed IR laser, allows IR mapping and gives access to local IR spectra at the subcellular level. A metal-carbonyl compound was internalized in cells and detected in the cell nucleus thanks to its IR signature. The local IR spectrum...