microliter

The microliter, abbreviated μL, is a unit of volume in the metric system equal to one millionth of a liter. It represents 10^-6 liters, which is 0.001 milliliters and, equivalently, one cubic millimeter (1 mm^3).

Microliters are widely used in science and medicine to measure small volumes of liquids. They are common in chemistry, biology, clinical laboratories, and molecular techniques where precise, small-volume transfers are required. Measurement is typically performed with micropipettes or automated liquid handling systems that are designed to dispense volumes within the microliter range.

Notation and spelling vary by region. The unit can be written as microliter (American English) or microlitre (British English). The standard symbol is μL, using the Greek letter mu. In contexts where the mu character is not available, uL is often used as a substitute.

Conversions and relation to other units are straightforward: 1 μL = 0.001 mL = 0.000001 L, and 1000 μL = 1 mL. Since 1 L equals 1000 mL, a liter is 1,000,000 microliters. The liter is a non-SI unit accepted for use with SI units, while the microliter is a derived unit in the metric system.

In practical terms, a microliter is a small, precise volume commonly encountered in analytical procedures, sample preparation, and diagnostic assays.