Used in physiological research and laboratory settings to maintain tissue viability during experiments. Provides an isotonic environment with balanced electrolytes, including sodium, potassium, calcium, and chloride, making it suitable for rinsing tissues, diluting medications, and supporting isolated organs such as hearts, smooth muscles, or intestines. Commonly used in ophthalmology for eye irrigation. Also utilized in laboratory procedures involving cell cultures, tissue preparations, drug testing, muscle contraction studies, neuronal electrophysiology, or vascular responses where a simple electrolyte solution is needed.

Unlike buffered versions, this un-buffered solution does not maintain pH stability on its own; in experiments requiring pH control, additional buffers (e.g., sodium bicarbonate) or gas mixtures (e.g., CO₂/O₂) may be added. It is not intended for direct intravenous injection or clinical use in humans due to lack of effective pH buffering.