Traditional clinical parasitology is based upon the diagnostic combination of two procedures: the concentration and the permanent smear. Historically these two procedures have required the use of two separate fixatives: a heavy metal PVA for the permanent smear and formalin for the concentration.
Although utilized for concentration procedures, formalin distorts protozoan trophozoites and juvenile nematodes. LV-PVA contains mercury chloride which is extremely toxic and environmentally hazardous. The viscosity of any PVA-based fixative prevents concentration and direct LCA and EIA procedures. PVAs containing other heavy metals (zinc & copper) have similar problems and do not provide staining results comparable to LV-PVA or Proto-fix™ CLR.
Until now, products attempting to overcome these limitations have been partially effective at best. Alpha-Tec Systems has set the new standard in parasitology with Proto-fix™ CLR.