Sub-microlitre Volumes of normal koala, mouse, dog, rat and cat tears were
fractionated using size exclusion-high performance liquid chromatography (S
E-HPLC), giving reproducible profiles which were different for each species
. Microlitre volumes of tears were also fractionated using sodium dodecylsu
rphate-polyacrylamide gel electrophoresis (SDS-PAGE), resulting in good sep
aration of individual tear proteins with a species specific distribution. T
ears from koalas with conjunctivitis and mice with keratitis were similarly
examined and showed mostly quantitative changes. These simple, rapid techn
iques gave reproducible results and, in contrast to conventional separation
techniques, used easily obtainable Volumes (as little as 0.75 mu l) of tea
rs. Their expansion could allow isolation, identification and quantitation
of individual tear components, enabling effective investigation of changes
occurring in disease. (C) 2000 Harcourt Publishers Ltd.