Drummond capillaries

The specific gravity d of an oil is the weight of a given volume of the oil at a specified temperature compared with the weight of an equal volume of water at the same temperature, all weights being taken in air. Generally a pycnometer or Drummond capillaries are used for determination. 

Remove excess medium with a fine-drawn 25-pL Drummond microdispenser capillary tube with a mouth attachment. Leave on a tiny amount of medium so that the explants do not dry out. 

Injection needles are prepared from S -in. hard glass capillaries (Drummond 3-000-203-G/X) using a Narashige PN-3 horizontal micropipette puller (Narishige International). 

A series of standard solutions of cholesterol were prepared by serial dilution. Equal volumes (2 pi) of a solution of known concentration of the sample and of each of the standard solutions were spotted on to the adsorbent alternatively. For high accuracy a micrometer syringe should be used, but also, a capillary pipette (Drummond Microcap), could be used. 

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