Ammonium molybdate tetrahydrate is used in cryo-negative staining and helps visualize particles while preserving the sample. Cryo-negative staining with Ammonium molybdate has been used to visualize Escherichia coli chaperone GroEL, 20S proteasome from moss, tobacco mosaic virus, bacateriophage T2, tomato bushy stunt virus (TBSV), bovine liver catalase crystals, turnip yellow mosaic virus and keyhole limpet hemocyanin (KLH) TYPES 1 and 2. Ammonium molybdate tetrahydrate has been used to catalytically desulfurize thiophene and its derivatives