To calculate the internal volume (V), you need to know the length of tubing (L) and the inner diameter (ID). You then use the formula for volume of a cylinder.

Convert L and ID into cm first. (1 inch = 2.54 cm). This gives V in cm3. 1 cm3 = 1 mL. You can then convert into µL if desired by 1000µL = 1mL.

V = π (ID/2)2 L

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