Figure 1. Fire-polished Pasteur pipette and 18 mm cover glasses with attached paraffin dots.

Fire-polish the tip of the Pasteur pipette with a Bunsen burner. The tip should melt to form a glass bead with a diameter of approximately 2 mm (while heating the tip of the pipette, rotate it around the longitudinal axis to form a symmetrical bead), and the pipette should be bent by an angle of 50°–80° approximately 3 cm from the end of pipette.