A New Method of Testing Blood Cells in Native Smears in Reflected Light

摘要

A new method of colour visualisation of red blood cells without using any chemical staining has been developed. The method is based on a physical phenomenon, the white light interference on thin transparent films. It is shown that in the case of thin human blood smears, colour interference contrast occurs on solid polished substrates. The best contrast was determined on substrates with maximal refractive index (Mo, W, Si). These materials have been selected as the substrate, in place of ordinary microscopic slides used in reflected light microscopy. It has been shown that reflection of incident white light from the blood cell surface and cell-substrate interface, generates two coherent lights. The object signal after passing through the red blood cell gathers additional phase and after interference interaction with reference signal (light reflected from outer cell surface) enables cell imaging in colour. A number of blood smears of healthy persons (control) and patients who were diagnosed with cancer have been analysed. It is concluded that the proposed method may be used as an effective diagnostic tool for detection of early stage blood cell lesions, by examining their interference colour in white light. This method can be used in research laboratories, hospitals, diagnostic centres and for emergency medicine as a diagnostic tool complementary to existing conventional optical and electron microscopy techniques.