SOP – Malaria Microscopy - NVBDCP

Quality Assurance of Malaria Diagnostic tests8.3.4.2 JSB II• measure 500 ml of distilled water into a flask and add 1.0 gm of eosin and stirthe whole solution.• leave this solution for 48 hours at room temperature for maturation beforeuse.8.3.4.3 Buffer water (pH 6.2 - 6.8)8.3.5 Staining• the ideal pH of water desirable for staining in JSB solution should rangebetween 6.2 to 6.8.• to prepare buffer wash water, in 1000 ml of distilled water in a flask, add disodiumhydrogen phosphate (0.22 gm) and potassium acid phosphate (0.74gm).• thoroughly stir the solution in order to dissolve the ingredients.8.3.5.1 Preparation for staining• before staining, filter both the JSB I & II. Keep used filter papers daily till thesupervisory visit by a senior officer or supervisory technician. All these filterpapers must contain dates.• change buffer water daily.8.3.5.2 Method of staining• dip the thin smear in methyl alcohol for a second or two for fixation.• thick smear contains more blood, therefore, if not stained immediately smearsare over dried and has to be dehaemoglobinised before staining.• dry thoroughly in the air.• immerse the thick & thin smears in solution II for a second or two.• wash twice or thrice in a jar containing buffer water (pH 6.2-6.8).• then immerse in solution I for 45 seconds.• wash 3 or 4 times in buffered water.• dry in air.8.3.5.2.1 Dehaemoglobinisation of thick smear• dip dried thick blood smears once into a beaker containing normal water andtake out immediately.• care should be taken during the process as sometimes the thick smear iswashed off.• do not touch or wipe the wet smear.• however, in freshly prepared slides, dehaemoglobinisation is not required.• alternatively, keep the dried smears flat and add 2/3 drops of normal water onthe dry smears.• after 30 seconds, the slide is ready for staining.• care should be taken not to wet the thin smears during the process ofdehaemoglobinisation.SOP – Malaria Microscopy© Copyright to Dte. NVBDCP Only. Any modification are prohibited