(Linen Thread, Sterile, in Distributor for Veterinary Use, Ph. Eur. monograph 0608)
DEFINITION
Sterile linen thread in distributor for veterinary use consists of the pericyclic fibres of the stem of Linum usitatissimum L. The elementary fibres, 2.5-5 cm long, are assembled in bundles 30-80 cm long and spun into continuous lengths of suitable diameter. The thread may be creamy-white or may be coloured with colouring matter authorised by the competen authority. The thread is then sterilised.
IDENTIFICATION
A. Dissect the end of a thread, using a needle or fine tweezers, to isolate a few individual fibres. Examined under a microscope, the fibres are seen to be 12-31 μm wide and, along the greater part of their length, have thick walls, sometimes marked with fine longitudinal striations, and a narrow lumen. The fibres gradually narrow to a long, fine point. Sometimes there are unilateral swellings with transverse lines.
B. Infrared absorption spectrophotometry (2.2.24). Examine by attenuated total reflection (ATR).
Absorption maxima and intensities: 3326 ± 10 cm-1 (medium); 2911 ± 12 cm-1 (medium); 1645 ± 10 cm-1 (weak); 1426 ± 5 cm-1 (medium); 1315 ± 3 cm-1 (medium); 1154 ± 7 cm-1 (medium); 1104 ± 5 cm-1 (medium); 1050 ± 5 cm-1
(strong); 1026 ± 7 cm-1 (strong).
TESTS
It complies with the tests prescribed in the monograph Strands, sterile non-absorbable, in distributor for veterinary use (0605).
If stored in a dry state, expose to an atmosphere with a relative humidity of 65 ± 5 per cent at 20 ± 2 °C for 4 h immediate before measuring the diameter and for the determination of minimum breaking load immerse in water R at room temperature for 30 min immediately before carrying out the test.
STORAGE
See the monograph Strands, sterile non-absorbable, in distributor for veterinary use (0605).
LABELLING
See the monograph Strands, sterile non-absorbable, in distributor for veterinary use (0605).
