A sample preparation for automated cervical cancer screening

A procedure for cluster disruption, cell dispersal and the production of a monolayer of cells from fluid suspensions for automated cell-scanning machines in an interactive system has been developed. The combination of 0.1 per cent dithiothreitol and 40 per cent alcohol in a balanced salt solution provides a self-limiting form of mucolysis which is completed by a controlled syringing regime to produce an optimally dispersed cell sample without the production of cell debris from the more effete cells. The induction of a positive charge on a microscope slide to attract the negatively charged cells has been achieved by coating the slides with the cationic polymer, polylysine. The cells appear to be sufficiently well attached to permit wet fixation and subsequent stain processing without loss. Quantitative data is given to demonstrate the superior cell presentation that is achieved by this new technique for automated scanning.