English to Spanish Science Biology (-tech,-chem,micro-) biochemistry

Greeting.
The part °fine coil° don't know if just need to be literally translated or is about another thing.
Thanks for your working.

An overview of the chemistry, manufacture, environmental fate and detection of carbofuran
The analyte (or sample mixture) is injected in solution and rapidly vaporised at the injection
port. The latter is the fi rst point of contact between the sample and the column, usually a fine coil of
silica capillary tubing, often several metres (e.g., 15 to 30) long, which is held within its own tightly
controlled heating compartment. The sample is heated in the injection port and swept through the
column held within the oven compartment by a carrier gas (the mobile phase), which is usually
helium (Grob and Barry 1995). The column is maintained at either a fi xed temperature, or, a series
of increasing temperatures can be applied. Depending on the analyte(s) of interest, and the thermal
stability of the GC column, the column temperature can be as high as 350ºC.