Research Projects

Microarray

Microarray printing procedure:

1. Check the washing bath solution and the water in sonication bottle. If getting low, fill them.

2. If temperature and humidity control required, turn on the water-cooling system and check the desiccant (regeneration may be needed).

3. Place spotting and blotting slide.

4. Place source plate.

5. Setup/humidity control: if required, set the desired humidity and chamber temperature. Wait the spotter condition reach the setting, this may take 30min~1h

6. Arraying/Define Arraying --> Create new arraying run, or Open an existing run.

    If select Create new arraying run, the following procedure is required:

    1. Substrates:

        Select slides as substrates and program the number of slides needed and the slide arrangement

    2. Grid layout:

         a. 96 as source plate.

         b. Select the pin type used and set the number of pin, arrangement and distance.

         c. Click Advanced and set:

             Print margin

             Distance between spots

             Number of spots per grid

             Number of replicate spots per grid

             Number of reprints of the same spot

             Grid printing direction

         d. If more than one grid needs to be printed:

             To produce replicate grid, set the number of replicate grid and the distance between grids.

             To print different grid, set the number of different grid, the distance between grids and printing direction.

         e. Set sample picking direction in source plate.

         f. Click accept grid layout.

         g. Click Apply.

         f. Click OK.

7. Before running the experiment, click Homing.

8. To start the experiment, click Run Robot Program.

Microarray reader procedure:

1. Turn on the instrument.

2. Open the program, ScanArray Express.

3. Wait until PC and reader connected. (Sometimes reopen program is required)

4. Turn on the laser required and wait 15min to stabilize.

5. Click Scan:

    a. For normal scan, select Run Easy Scan. Or a scan protocol can be programed as well.

    b. Set the resolution, fluorophore type PMT gain.

    c. Set the scan area.

    d. Click start.

Functional Medical Imaging

The main aim of this project is the generation of highly targeted multimodal and biocompatible mesoporous silica nanoparticles (MSNs) that can act as:

• ·Highly luminescent fluorescent labels of cells
• ·Targetable very high MRI contrast agents
• ·Efficient and targeted cell killers

(above) TEM micrographs of MSNs showing particle diameter ranging from 60 to 80 nm and pore size of 3 nm.

Spectral confocal analysis of cancerous Hela cell showing an overlap of the stained green endosomes and the red fluorescent MSN particles (fMSNs), generating yellow and indicating co-localisation of fMSNs in endosomes after 5h.

Model for surface functionalisation and biomodification of nanoparticles with variable/highly tuneable cores

In collaborating work with a team in the Department of Engineering Science we are developing functionalised mesoporous nanoparticles in order to achieve selective delivery of hydrophobic antibacterials to bacterial cells with particles which are, otherwise, unvectored.

A variety of multimodal nanoparticle architextures encapsulating paramagnetic or NMR resonant atoms and organic fluorophores for fluorescence and targetted T1 / T2 MRI imaging are being developed (functional fluorine and Gd triggered imaging).   A specific focus is the generation of high relaxivity, kinetically sytable nanoparticle payloads that can be vectored to specific cell types.

(Above, lower right) - high T1 image contrast from stem cells loaded with Gd doped luminescent silicate nanoparticles

Much of this work is in collaboration with teams in Physiology (Oxford - Stem Cell Tracking) and Leeds (Mesenchymal Stem Cell imaging). 

The uptake mechanisms, passive/triggered toxicity and subcellular localisation of  these particles are also a particular focus.

Engineering the Bioelectronic Interface

This program, is associated with controlled modulation of the electrochemical & mechanical coupling between metalloproteins, enzymes and man-made electrode interfaces. This modulation makes use of both genetic manipulation of the protein interfacial characteristics and surface chemistry. Through control of surface-bound orientation of these molecules the tunnelling distances, and so the rates of electron transfer, can be controlled. Such controlled bioelectrochemical coupling is both routinely studied at the molecular level and utilised in the generation of enzyme-derived sensory systems. Many of the principles associated with this work are aided by routine molecular-scale analysis.

Surface Assembled Switchable & Interlocked Receptors

In collaborative work with Professor Paul Beer, interlocked catenanes and rotaxanes are assembled on optically transparent and metallic surfaces (including nanospherical).

These assemblies are subsequently characterised by a range of spectroscopic and imaging methods and utilised both in developing uniquely specific host reporters and in progressing towards switchable molecular-scale devices.