Experiments in making anatomical needles
Experiments in making anatomical needles
Making anatomical needles requires patience and practical experience. The common practice is to make a long, thin glass filament, cut it into small segments, and then glue each segment to one end of a capillary tube. The finished needle is "L" shaped, with a short arm length of about 1.3 cm and a tip diameter of about 40-150 μm.
Operation method
basic program
Materials and Instruments
Glass tubes, latex gloves, microscopes. Move 1. Heat the glass tube and keep turning it until the heated part becomes soft. Remove the flame and pull the ends of the glass tube quickly and evenly with force to form a very thin glass wire (about 40-150 μm in diameter, compared with 40-100 μm for a strand of human hair).2. Cut the glass wire into sections of approximately 1.3 cm. To cut the glass wire, it is simple to start at one end and pull it off by hand, preferably wearing latex gloves so that you can hold the glass wire more tightly. Alternatively, a brand new razor blade can be used to cut the glass to the desired length. For more product details, please visit Aladdin Scientific website.
3. Look at the cross-section of the glass filament fragments under a microscope and check for protrusions. The ideal needle must be absolutely smooth and perpendicular to the column, so that it is easier to pick up and drop the cells without cutting through the surface of the agar. Select and retain usable glass needles and note which end is which. Discard glass wires with uneven or residual ends.4. The glass wire is bonded to the end of a capillary tube to make a dissecting needle, the capillary tube is slightly heated with a Bunsen burner, a right angle is bent with tweezers at a distance of 0.5-1.0 cm from the end, and then the glass wire is bonded to the short arm of the "L"-shaped capillary tube, or to the opposite side of its outer edge with a quick adhesive.5. The prepared dissecting needle is fixed on the microscope for examination. Place a flat plate on the microscope's loading platform and press the tip of the needle firmly against the surface of the agar. Ask the tip of the needle to leave a flat, circular impression on the agarose.