Optical Microscopy

The BMM is based around a Nikon TE2000 inverted fluorescence microscope. It is used to manipulate and probe the micro-mechanics of membranes. The system can be used successfully to investigat both model lipid membrane giant vesicles and living cells.

The microscope has both epi-fluorescence illumination with a variety of visible and UV filter sets and bright filed Hoffman modulation contrast optics giving extreamly clear imaging of aspirated unilamellar vesicles.

A custom produced sample holder gives precise temperature control via water circulation. The sample holder is fitted to a precission motorised stage.

The test membrane is probed by applying a negative pressure via a fine micropipette, by measuring the applied pressure and the distance that the membrane is aspirated (sucked up the pipette) various micro-mechanical parameters can be extracted such as area expansivity modulus and bending rigidity.

The micropipette is positioned using a three axis precission micromanipultor with a specified resolution of 25nm while the pressure is applied using an in-house developed motorised manometer system with an ultra-high resolution pressure transducer to measure the applied pressure.

Images are recorded at high speed (up to 160 frames per second) with a digital firewire CCD camera.

The system is integrated and controlled using in-house developed software. This allows control and triggering of pressure, image capture and microscope components which can allow multi-channel imaging of complete aspiration progressions.

The Olympus IX81 is an inverted fluorescence microscope. It has a microfluidics set up allowing direct imaging in either bright field or fluorescence of microfluidic devices and materials flowing inside them.

Our Leica DM IRBE microscope is an inverted fluorescence system with filters covering the full visible spectrum. It has a CCD camera for image capture and is routinely used for imaging a large variaty of fluorescent samples but is often used for imaging lipid films and patterns formed using microcontact printing and has recently been equiped with an in-house developed system for imaging lipid films in-situ during microcontact priniting.

Our Nikon E600Pol polarising microscope is a commercial polarising microscope system. It is routinely used for phase and composition determination in hydrated lipid samples.

The microscope has a Linkam heating/cooling stage to allow temperature control accurate to 0.01°C.

Images are captured using a Nikon full colour CCD camera with a maximum resolution of 12 megapixels.

We have got a number of other microcopes including a one specially adapted to look at materials flowing under gravity, a Nikon TE200 fluorescence microscope, a laser scanning cytometer system and several smaller microscopes.

We also have access to the Imperial College London, Facility for Imaging by Light Microscopy, which runs a series of high performance wide filed fluorescence microscopes and several confocal systems including two with multi-photon capability.