Nanodiamonds for bioimaging and drug delivery
Lead Research Organisation:
University of Liverpool
Department Name: Chemistry
Abstract
Nanodiamonds have sparked great interest in various industries due to their high chemical inertness, low toxicity and small particle size; such properties render them particularly suitable for biomedical applications. In collaboration with Element 6 Ltd, this project aims to explore the use of nanodiamonds as contrast agents for photoacoustic imaging and as stabilisers in nano-dispersion techniques to improve the solubility of poorly water-soluble drugs. Organic dyes with absorption in the near-infrared region will be attached to nanodiamonds to improve the resolution and penetration depth in photoacoustic imaging, a technique being investigated as an improvement to conventional imaging techniques. The efficiency of these imaging probes to improve image contrast will be investigated in vivo in the Department of Physiology. Additionally, the nanodiamonds will be investigated as potential stabilisers in emulsion freeze-drying techniques, developed by Dr Haifei Zhang's group, to improve drug solubility; a problem which hinders the efficacy of many potential drug candidates.
People |
ORCID iD |
| Haifei Zhang (Primary Supervisor) | |
| Claudia Fryer (Student) |
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/N509693/1 | 01/10/2016 | 30/09/2021 | |||
| 1938095 | Studentship | EP/N509693/1 | 11/09/2017 | 11/09/2021 | Claudia Fryer |
| Description | Nanodiamonds have been investigated as probes for in vivo stem cell tracking using bioimaging techniques, including photoacoustic and fluorescence imaging. Nitrogen vacancy defect (NVD) nanodiamonds show high fluorescent signal and good uptake into mesenchymal stromal cells (MSC), suggesting their potential for ex vivo cell tracking studies. Non-NVD nanodiamonds have limited signal but show good uptake into MSCs with limited effect on cell viability. Attaching a near-infrared absorbing perylene diimide (PDI) dye to the surface of non-NVD nanodiamonds did not improve the photoacoustic or fluorescence signal, likely due to poor loading and particle aggregation. Therefore these probes are not suitable for cell tracking with photoacoustic imaging. PDI nanoparticles were also prepared via nanoprecipitation with a polymer stabiliser. These nanoparticles showed superior photoacoustic signal and can hence be used as cell tracking probes. The PDI nanoparticles are now being incorporated into collagen gels for cell encapsulation, so that gel integrity can be monitored in vivo. |
| Exploitation Route | The perylene diimide (PDI) nanoparticles prepared by nanoprecipitation can be used as cell tracking probes for photoacoustic imaging in rodent models, thus allowing information to be gathered on the fate and biodistribution of transplanted stem cells. This will aid the design of regenerative medicine therapies. Nanodiamonds had poor signal and were not suitable for photoacoustic imaging, however the project highlighted their good uptake into cells with limited cytotoxicity. This suggests that it is worth investigating whether nanodiamonds can be used for other biomedical applications. |
| Sectors | Pharmaceuticals and Medical Biotechnology |