Special thermal processing techniques used to make phosphate glass fibres for the regeneration of highly oriented human tissues at University College London
The Eastman Dental Institute at University College, London, is using special thermal processing techniques to make phosphate glass fibres for applications such as the regeneration of highly oriented human tissues.
Researchers believe the fibres could act as a temporary scaffold for genetically modified cells which could then be grown to form tissue.
Samples for evaluation are produced by melting pieces of glass in a furnace specially built by Lenton Thermal Designs.
The equipment provides a maximum operating temperature of 1500C and includes a number of special features to ensure close temperature control, minimise contamination, and provide convenient sample handling.
The glass is melted in a crucible, 100mm high x 68mm diameter, with a bushing in the base incorporating a 1mm diameter hole through which the molten material flows when a plug is withdrawn.
The molten glass is then picked up by a servo-controlled drum and pulled so that it reduces down to the appropriate diameter - between 5µm and 200µm.
The crucible is loaded through a door on top of the furnace, which gives convenient access for topping it up with raw material without reducing temperature.
Sample contamination has been minimised by using a platinum crucible, a stainless steel case, and silicon carbide tiles to line the furnace lid.
Very precise temperature control has been achieved by positioning a thermocouple close to the crucible bushing where the glass exits and also incorporating a 'cascade' control system which produces accurate heat output from the elements.
Over-temperature protection is also included.
