Objectives

Biophotonics is currently a very active and promising field of research aimed at making progress in life sciences through novel photonic technologies. One important subarea of biophotonics is bio-imaging where imaging technologies, such as fluorescence microscopy, are used to get a better understanding of the interaction of biomolecules or nanomatter with biological materials and living organisms. This driver encompasses three research lines:

1. Nanoparticle characterization in biological fluids

Developing functional nanoparticles is of great interest for drug delivery and biomedical imaging. To obtain a successful and safe product, accurate characterization of nanomaterials is a prerequisite, not only in simple solvents but also in biological media. The effective size and nanoparticle concentration are amongst the most important parameters that directly influences the nanoparticle in vivo processing and biodistribution. Our aim is to address the current need for methods that allow to measure the nanoparticle size distribution and concentration in undiluted biological fluids, such as blood. Suitable algorithms based on single particle tracking microscopy will be worked out and an optofluidic lab-on-chip device will be developed for miniaturized and automated nanoparticle size, concentration and stability measurements.

2. Labeling of living cells with quantum dots and nano-cytotoxicity

Fluorescence visualization of live cells and specific intracellular structures is an essential research tool in cell biology and drug delivery. Quantum dots (QDs) provide an attractive alternative class of labels over classic organic fluorophores since they are much brighter and have a superior photostability. However, labeling of intracellular structures by QDs in living cells has had very limited success so far due to the inefficient translocation of QDs into the cytosol. In this project we will investigate chemical and physical methods to deliver QDs into living cells for subcellular labeling. The uptake by the cells, intracellular trafficking, endosomal release, subcellular labelling and cytotoxicity will be carefully analyzed for different delivery methods using advanced microscopy techniques. Special attention will be given to the toxicity of different types of quantum dots since this is of major concern for live cell labeling.

3. High-content screening and in fluxo analysis of living cells

Light microscopy plays a crucial role in evaluating the response of living cells to a changing environment. Until now, microscopic analyses of cellular behaviour have typically been performed manually. However, manual selection is biased by operator subjectivity and is limited by the number of cells that can be analysed per experiment. To address these issues we will enable cell-based assays in a high-content (= much information per image and object), high-throughput (= many images acquired at high speed) setting. In parallel, microfluidics systems will be evaluated for performing such assays under controlled flow (=in fluxo) so as to accurately control the delivery of external compounds to the cells. This technology will then be applied to a number of projects, including nano-cytotoxicity, cell adhesion and intracellular trafficking of nanoparticles for drug delivery, receptor activation by bio-active peptides and biomarker detection for pathologies.

Groups involved and main tasks

• LGBPP: Development of optofluidic chip and composite nanoparticles for bio-imaging
• PRG: Optical simulations and microfluidics
• LCP: Waveguide design and development
• PCN: Development of IR quantum dots
• CSI: Genetic engineering, Cell imaging, biomonitoring and toxicity screening.
• PBM: Functionalization of nanoparticles for bio-imaging
• Associated partner Laboratory of Gene Therapy: In vivo studies of nanomedicines for gene therapy

Coordinator

Kevin Braeckmans (LGBPP)

Research Team

Subline 1: Nanoparticle characterization in biological fluids

• Kevin Braeckmans, professor (LGBPP)
• Kristiaan Neyts, professor (LCP)
• Peter Dubruel (PBM)
• Niek Sanders, professor (associated partner)

• Katrien Remaut, post-doc (LGBPP): advanced fluorescence microscopy techniques for studying intracellular stability of nanomedicine formulations
• Sandra Van Vlierberghe, post-doc (PBM): functionalization of nanoparticles for drug delivery

• Hendrik Deschout, joint PhD student (LGBPP, LCP): Optofluidics chip for sizing and counting of nanoparticles in biofluids
• Elisa Zagato , joint PhD student (LGBPP, LCP): Optofluidics chip for sizing and counting of nanoparticles and intracellular imaging with light-sheet microscopy
• Thomas Martens, PhD student (LGBPP): Transport investigation of nanomedicines by advanced microscopy techniques in vitreous, retina and in living cells of nanomedicines for gene therapy
• Katrien Forier, PhD student (LGBPP): Transport investigation of nanomedicines by advanced microscopy techniques in biofilms and mucus for drug delivery of antimicrobial agents
• Koen Rombouts, PhD student (LGBPP): advanced fluorescence microscopy techniques for studying intracellular stability of nanomedicine formulations
• Katrien Remaut, post-doc (LGBPP): advanced fluorescence microscopy techniques for studying intracellular stability of nanomedicine formulations
  
  

Subline 2: Labeling of living cells with quantum dots and nano-cytotoxicity

• Kevin Braeckmans, professor (LGBPP)
• Zeger Hens, professor (PCN)
• Stefaan Soenen, postdoc (LGBPP): Intracellular delivery of nanoparticles and nanoparticle-induced cytotoxicity
• Tangi Aubert, postdoc (PCN): functionalized quantum dots with reduced nanocytotoxicity
• Sangram Keshari Kama, postdoc (PBM): functionalized quantum dots with reduced nanocytotoxicity
• Sofie Abé, PhD student (PCN): Functionalized quantum dots for bio-labeling
• Ranhua Xiong, joint PhD student (LGBPP, CSI): SPR active gold nanoparticles for drug delivery applications

Subline 3: High-content screening and in fluxo analysis of living cells

• Els Van Damme, professor (CSI)
• Patrick Van Oostveldt, em. professor (CSI)
• Kevin Braeckmans, professor (LGBPP)
• Winnok De Vos, postdoc (CSI): Advanced fluorescence microscopy and high-content/high-throughput cell screening
• Stefaan Soenen, post-doc (LGBPP): high-content/high-throughput screening of nanocytotoxicity assays
• Tom Sieprath, PhD student (CSI): Advanced fluorescence microscopy and high-content/high-throughput cell screening
• Tobias Corne, PhD student (CSI): Advanced fluorescence microscopy and high-content/high-throughput cell screening