Cyrille Richard | Université Paris Descartes (original) (raw)

Papers by Cyrille Richard

Advanced Optical Materials

Nanoscale

A one-year fellow up of ZGO nanoparticles in vivo: protocol and characterizations.

The Journal of Physical Chemistry C, 2020

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

The Analyst, 2021

The interactions between NPs and a binary system of proteins were studied through a systematic se... more The interactions between NPs and a binary system of proteins were studied through a systematic set of capillary electrophoresis models. The results revealed precise details of the soft and hard protein corona formation and dynamics.

Advances in Optics and Photonics, 2016

The tremendous progress in the synthesis of different inorganic nanoparticles with pretailored si... more The tremendous progress in the synthesis of different inorganic nanoparticles with pretailored size, shape, structural, compositional, and surface properties has significantly raised their potential applications in biomedicine. Optically active inorganic nanoparticles are those that, based on inorganic materials, can produce fluorescence or scattered light under suitable optical excitation. These outgoing radiations can be conveniently used for bioimaging purposes. In this work, the different types of optically active inorganic nanoparticles that are being used for optical bioimaging are reviewed in detail. Special attention is paid to fluorescent and inorganic persistent luminescence nanoparticles and how their different excitation mechanisms (no-photon, one-photon, or multiphoton excited fluorescence) and working spectral ranges can be conveniently applied for in vitro and in vivo high-contrast optical bioimaging.

International journal of pharmaceutics, Jan 10, 2017

The ZnGa1.995Cr0.005O4 persistent luminescence nanoparticles offer the promise of revolutionary t... more The ZnGa1.995Cr0.005O4 persistent luminescence nanoparticles offer the promise of revolutionary tools for biological imaging with applications such as cell tracking or tumor detection. They can be re-excited through living tissues by visible photons, allowing observations without any time constraints and avoiding the undesirable auto-fluorescence signals observed when fluorescent probes are used. Despite all these advantages, their uses demand extensive toxicological evaluation and control. With this purpose, mice were injected with a single intravenous administration of hydroxylated or PEGylated persistent luminescence nanoparticles at different concentrations and then a set of standard tests were carried out 1day, 1 month and 6 months after the administration. High concentrations of hydroxylated nanoparticles generate structural alterations at histology level, endoplasmic reticulum damage and oxidative stress in liver, as well as rising in white blood cells counts. A mechanism inv...

Optical Materials, 2017

The analysis of the optical spectroscopy of the Cr 3þ doped spinel was initiated by Prof. Georges... more The analysis of the optical spectroscopy of the Cr 3þ doped spinel was initiated by Prof. Georges Boulon more than twenty years ago. More recently persistent luminescence nanoparticles of Cr doped zinc gallate have found interest for in vivo imaging of small animals. Here we evaluated near infra-red (NIR) excitation (or NIR photostimulation) via photo-transfer mechanism as an additional tool for in vivo optical imaging. Investigation of the persistent luminescence induced by NIR photostimulation is studied after either a primary UV (band-to-band excitation) or visible irradiation (direct Cr 3d-3d excitation). UV or visible pre-excited ZnGa 2 O 4 :Cr (ZGO:Cr) nanoparticles are kept active during several days thanks to deep traps (with depths 1 eVe1.2 eV) observed in these samples which can be probed through thermally stimulated luminescence (TSL) technique showing glow curve maximums at 470 K and 530 K upon visible light excitation. These deep traps are stable at room temperature but can be emptied by NIR light photostimulation. Experiments were carried out to study the photostimulation induced trappingdetrapping in the ZGO:Cr phosphor. Photostimulation was also tested in vivo for small animal optical imaging to offer new perspectives and modalities.

Journal of Luminescence, 2016

Biocompatible nanoparticles possessing persistent luminescence properties offer attractive possib... more Biocompatible nanoparticles possessing persistent luminescence properties offer attractive possibilities for in vivo imaging applications as it allows an excitation of the sensors outside the animal before injection and a long-lasting emission of light. Here we report the development of highly biocompatible calcium phosphate nanoparticles doped with europium, Mn2+ and Ln3+ (Ln3+=Dy3+, Pr3+) ions synthesized by hydrothermal route and tailored to present red-near infrared persistent luminescence after UV excitation. Nanosize biphasic HAp/β-TCP compounds with sphere and rod-shaped were obtained. Two emission bands in the red-near infrared range were observed and attributed to 4T1→6A1 transitions of Mn2+ ions in HAp/β-TCP. An annealing treatment in reductive atmosphere post-synthesis was essential to reveal persistent luminescence properties. Indeed, such thermal treatment allows reducing Eu3+ ions in Eu2+ ions and generating required defaults as oxygen vacancies in the crystal necessary for red emission in accordance with persistent luminescence mechanism. These nanoparticles have been tested for the first time for in vivo imaging on small animal as proof of concept of prospective highly biocompatible nanoprobes.

Materials

The property of persistent luminescence shows great potential for anti-counterfeiting technology ... more The property of persistent luminescence shows great potential for anti-counterfeiting technology and imaging by taking advantage of a background-free signal. Current anti-counterfeiting technologies face the challenge of low security and the inconvenience of being limited to visible light emission, as emitters in the NIR optical windows are required for such applications. Here, we report the preparation of a series of Zn1+xGa2−2xSnxO4 nanoparticles (ZGSO NPs) with persistent luminescence in the first and second near-infrared window to overcome these challenges. ZGSO NPs, doped with transition-metal (Cr3+ and/or Ni2+) and in some cases co-doped with rare-earth (Er3+) ions, were successfully prepared using an improved solid-state method with a subsequent milling process to reach sub-200 nm size particles. X-ray diffraction and absorption spectroscopy were used for the analysis of the structure and local crystal field around the dopant ions at different Sn4+/Ga3+ ratios. The size of th...

International Journal of Pharmaceutics: X

Frontiers in Chemistry

Driven by the increasing concern about the risk of diclofenac (DCF) residues as water pollutants ... more Driven by the increasing concern about the risk of diclofenac (DCF) residues as water pollutants in the aqueous environment and the growing need for its trace determination, a simple but sensitive electrochemical aptasensor for the trace detection of DCF was developed. To construct the aptasensor, the amine-terminated DCF aptamer was covalently immobilized on the surface of the carboxylic acid–functionalized multi-walled carbon nanotube (f-MWCNT)–modified glassy carbon electrode (GCE) through EDC/NHS chemistry. The f-MWCNTs provide a reliable matrix for aptamer immobilization with high grafting density, while the aptamer serves as a biorecognition probe for DCF. The obtained aptasensor was incubated with DCF solutions at different concentrations and was then investigated by electrochemical impedance spectroscopy (EIS). It displays two linear ranges of concentration for DCF detection, from 250 fM to 1pM and from 1 pM to 500 nM with an extremely low detection limit of 162 fM. Also, th...

Light: Science & Applications

Trivalent lanthanides in wide bandgap fluoride or phosphate hosts can present persistent luminesc... more Trivalent lanthanides in wide bandgap fluoride or phosphate hosts can present persistent luminescence between 200 nm and 1.7 µm after charging by X-rays. Mechanisms are reviewed and applications envisioned.

Frontiers in Chemistry, 2020

Persistent luminescence nanoparticles (PLNPs) are innovative nanomaterials highly useful for bioi... more Persistent luminescence nanoparticles (PLNPs) are innovative nanomaterials highly useful for bioimaging applications. Indeed, due to their particular optical properties, i.e., the ability to store the excitation energy before slowly releasing it for a prolonged period of time, they allow in vivo imaging without auto-fluorescence and with a high target to background ratio. However, as for most nanoparticles (NPs), without any special surface coating, they are rapidly opsonized and captured by the liver after systemic injection into small animals. To overcome this issue and prolong nanoparticle circulation in the bloodstream, a new stealth strategy was developed by covering their surface with poly(N-2-hydroxypropyl)methacrylamide (pHPMA), a highly hydrophilic polymer widely used in nanomedicine. Preliminary in vivo imaging results demonstrated the possibility of pHPMA as an alternative strategy to cover ZnGa 2 O 4 :Cr NPs to delay their capture by the liver, thereby providing a new perspective for the formulation of stealth NPs.

Nanoscale, 2021

Optical in vivo imaging has become a widely used technique and is still under development for cli... more Optical in vivo imaging has become a widely used technique and is still under development for clinical diagnostics and treatment applications.

Near Infrared-Emitting Nanoparticles for Biomedical Applications, 2020

The development of nanoparticles for NIR imaging and diagnostics is an area of considerable inter... more The development of nanoparticles for NIR imaging and diagnostics is an area of considerable interest. Among the different imaging modalities, optics emerged has an interesting technique since it is a non-invasive, cheap imaging technique allowing real time imaging. In-vitro, this technique is very useful, however in-vivo fluorescence imaging suffers from suboptimal signal-to-noise ratio, which is caused by the strong tissue autofluorescence under constant external excitation. To address this limitation, novel types of optical nanoprobes are actually being developed in the deep red/near infrared (NIR) range and among them, persistent luminescence nanoparticles (PLNPs), with long lasting near-infrared luminescence capability. These NPs allow optical imaging to be performed in an excitation-free and consequently autofluorescence-free manner. This chapter will first introduce the physical phenomenon associated to the long luminescence delay of such nanoprobes, from minutes to hours after ceasing the excitation, and will then highlight the tools used in physico-chemistry laboratories to characterize these nanoparticles with a focus on the ZnGa2O4 nanoparticles which are widely studied over the world. Then their biocompatibility will be mentioned and finally the evaluation in term of new advances for in-vivo bioimaging theranostics nanoprobes will be presented. We will conclude this chapter by envisioning perspectives for such nanomaterials.

The Journal of Physical Chemistry C, 2021

Persistent luminescence and photochromism are two fascinating optical properties that involve cha... more Persistent luminescence and photochromism are two fascinating optical properties that involve charge trapping via defects and their release due to an external stimulation. In both processes, it is possible to define a "1" (or "on") and a "0" (or "off") optical state. Consequently, materials with one of these phenomena find major interest in view of designing smart, anticounterfeiting and optical information storage devices. Combining both processes within a single material can lead to a new generation of information storage phosphors, in which it may be possible to obtain three different optical states by playing on the external stimulations applied on the material. For that purpose, the elaboration of nickel-doped ZnGa 2 O 4 spinel transparent nano glass-ceramics is presented in this work. The shortwave infrared (SWIR) emission, a broad band located at ca. 1275 nm, arises from Ni 2+ cations located in gallium octahedral sites. SWIR persistent luminescence, arising from the same doping ion transition, can also be monitored after UV charging. Interestingly, UV irradiation

Nanoscale, 2019

Cr3+ doped nanoparticles (ZGO) with persistent luminescence properties have been dispersed in dif... more Cr3+ doped nanoparticles (ZGO) with persistent luminescence properties have been dispersed in different media. We have observed that among them, Artificial Lysosomal Fluid (AFL) that mimics the intracellular environment can degrade ZGO.