What is the impact of pipette tip geometry on injection efficiency ?

• Inner Diameter: A 5 µm ID closely fits the sperm head, reducing cytoplasmic leakage and drag.

• Bevel Length: Short bevels focus force; long bevels (>15 µm) can slide through the zona without clean cuts.

• Wall Thickness: Thicker walls resist bending but may reduce visibility; aim for ~1 µm wall thickness at the tip.