Preservatives

Crystals of EDTA-2K from a urinary sediment. EDTA-2K was added to the urine for preservative. Unstained, X400.

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Crystals of urea resin from a urinary sediment. The urea resin is made from urea in the urine and formalin, which was added to the urine for preservative, during preservation of the urine. These crystals are insoluble in 10% HCl, 10% NaOH, acetone, and chloroform. Unstained, X400.

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Droplets of toluene from a urinary sediment. The toluene was added in the urine for preservation. Sternheimer-Malbin stain, X400.

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