Which solvent is recommended to wipe the ointment slab before starting work?

Which solvent is recommended to wipe the ointment slab before starting work?

• A. 70% isopropanol
• B. 95% ethanol
• C. Water
• D. 70% methanol

Answer: (A)

Using a disinfectant with the right amount of water is key for effective cleaning of the ointment slab. A 70% solution of isopropanol is ideal because the water content facilitates protein denaturation and allows the alcohol to penetrate microbial cells more effectively, giving broad-spectrum antimicrobial action while remaining practical to use. Higher concentrations like 95% ethanol dry out and coagulate surface proteins too quickly, reducing penetration and kill. Water alone doesn’t disinfect, and methanol is toxic and not appropriate for this use. So, wiping with 70% isopropanol provides reliable surface disinfection for starting work.

Using a disinfectant with the right amount of water is key for effective cleaning of the ointment slab. A 70% solution of isopropanol is ideal because the water content facilitates protein denaturation and allows the alcohol to penetrate microbial cells more effectively, giving broad-spectrum antimicrobial action while remaining practical to use. Higher concentrations like 95% ethanol dry out and coagulate surface proteins too quickly, reducing penetration and kill. Water alone doesn’t disinfect, and methanol is toxic and not appropriate for this use. So, wiping with 70% isopropanol provides reliable surface disinfection for starting work.