Tag Archives: Wenjie Jason Chen

Gold nanoparticles for bioimaging

22 March 2017:

A new publication from CNBP researchers (lead author Sandhya Clement pictured) reports on a more effective and less harmful gold-based nano-agent for bioimaging and photodynamic therapy treatment for deep tissue tumors.

The work has just been reported in the journal ‘Microchimica Acta ’ and is accessible online.

Journal: Microchimica Acta.

Title: Verteprofin conjugated to gold nanoparticles for fluorescent cellular bioimaging and X-ray mediated photodynamic therapy.

Authors: Sandhya Clement, Wenjie Chen, Ayad G. Anwer & Ewa M. Goldys.

Abstract: Photodynamic therapy (PDT) uses photosensitizers, light and molecular oxygen to generate cytotoxic reactive oxygen species. Its effectiveness is limited to <1 cm due to the limited penetration depth of light. The present study compares the PDT effectivity of the photosensitizer verteporfin (VP) conjugated to gold nanoparticles (AuNPs) (a) by using deeply penetrating X-rays administered in standard radiotherapy doses, and (b) by using red light (690 nm). VP was conjugated to AuNPs of around 12 nm size to enhance the interaction of ionizing radiation with PS. For comparison, VP also was directly exposed to X-rays. It is found that VP alone is stimulated by X-rays to generate singlet oxygen. The conjugate to AuNPs also generated a significant amount of singlet oxygen on irradiation with X-rays in comparison to illumination with 690-nm light. It is also found that the rate of singlet oxygen generation is amplified in case of AuNP-conjugated VP compared to VP alone. The performance of the AuNP-VP conjugate and of the VP alone was tested in Panc 1 cells. Their viability was impaired much more in these two scenarios than with the X-ray radiation only. This suggests excellent perspectives for PDT based on VP and with X-ray stimulation, both as a stand-alone photosensitizer and in Au-NP conjugates. Moreover, both VP and AuNP-VP conjugates show bright fluorescence in physiological media for excitation/emission wavelengths in the range of 405/690 nm; hence they can also be used for simultaneous bioimaging.

Welcome to Kashif and Jason at MQ Node

17 April 2015:Kashif and Jason at MQ

Last week Macquarie node welcomed two new PhD students who joined Ewa Goldys’ group.

Kashif Islam (left) hails from Pakistan. His project is concerned with expanding the range of fluorophores that can be non-invasively quantified in cells and tissues. This work will have components of hardware development, photochemistry and photobiology.  Kashif  will be part of the hyperspectral team working with Martin Gosnell, Ayad Anwer, Biju Cletus, Saabah Mahbub and Aziz Rehman and external partners. We hope he will be able to observe tryptophan, kyneurenine and collagen, which will open up exciting options for CNBP.

Wenjie Jason Chen (right) came from China. He is developing specialised nanoparticles which will be targeted to receptors of interest and deliver their cargo following a trigger. He will be working with Wei Deng and external partners working towards translational medical objectives.

We are excited to have Jason and Kashif here and looking forward to seeing their results soon.