Iohexol is a non-ionic, water-soluble radiographic contrast medium. When sourcing, you must specify the concentration, typically ranging from 140 mgI/mL to 350 mgI/mL, depending on the clinical application (e.g., CT, angiography, or urography). The product must strictly adhere to international pharmacopoeia standards such as USP (United States Pharmacopeia), BP (British Pharmacopeia), or EP (European Pharmacopoeia). Key parameters to verify include osmolality, pH levels (6.8 to 7.7), and purity levels to minimize adverse patient reactions.