Absorbent Cotton
S G Gayal, Central Institute for Research on Cotton Technology, Mumbai
A process has been developed to make absorbent cotton from short staple cotton
using commercial pectinase preparation. The enzymatically prepared absorbent
cotton from Bengal Desi cotton variety fulfils the standard norms and qualities and
could find its application in biomedicine as surgical cotton.
Cotton consists of fibres or hairs which come out from cottonseeds. These fibres are
unicellular, flattened tubular structures. The cotton fibres vary in length from 20 mm to 40
mm and in width from 15 μm to 25 μm. The cotton fibres are separated and cleaned from the
seeds by a mechanical process called ‘ginning’.
Cotton fibres are basically cellulosic polymers. Raw unpurified cotton as such is hydrophobic
in nature, i.e. it does not absorb water, on the contrary it repels water. This hydrophobic
property of the cotton is due to the presence of non-cellulosic substances such as waxes,
pectins, proteins, etc. on the fibre. A typical chemical composition of cotton fibres is (%) :
cellulose, 94; waxes, 0.6; pectins, 0.9; protein, 1.3; mineral matters, 1.2; organic compounds
0.8; total sugars, 0.3.
Cotton is mainly used in textile for manufacturing fabric. However, cotton varieties such as
Bengal Desi or RG 8 are having fibre length less than 20 mm and generally are not suitable
for fabric making. Such short staple cotton could find alternative applications in the field of
biomedicines such as dressings, gauzes, bandages etc.
The basic raw material used for surgical cotton and dressings is the short staple raw cotton
fibres or the waste cotton fibres. The surgical cotton in biomedicine is used in three different
forms:
(a) Non-absorbent, bleached cotton
(b) Absorbent not bleached cotton
(c) Absorbent bleached cotton
For preparing absorbent cotton from native cotton, it is necessary to remove the noncellulosic
materials from the cotton. Conventionally, the absorbent cotton is made by treating
the cotton with alkali such as sodium hydroxide at boil and pressure. The process is called as
scouring process. In laboratory, the scouring is being done by treating cotton with 1.0%
NaOH 1:20 volume at 121° for 4 hr in an autoclave at a pressure of 15 Ib/in². The scoured
cotton is washed with water, 1% acetic acid and finally with water and dried.
Enzymes are biocatalysts and they bring about reactions under moderate conditions. In
textiles, many enzymes, such as amylase, cellulase, protease, pectinase, lipase find
applications. Enzymes such as lipase, cellulase, pectinase and protease could be used for
scouring of cotton and fabric.
A process has been developed at CIRCOT to make absorbent cotton from short staple cotton
using commercial pectinase preparation. The process consists of treating the Bengal Desi
with pectinase under optimum condition for 30 min, in the presence of wetting agent.
S G Gayal, Central Institute for Research on Cotton Technology, Mumbai
A process has been developed to make absorbent cotton from short staple cotton
using commercial pectinase preparation. The enzymatically prepared absorbent
cotton from Bengal Desi cotton variety fulfils the standard norms and qualities and
could find its application in biomedicine as surgical cotton.
Cotton consists of fibres or hairs which come out from cottonseeds. These fibres are
unicellular, flattened tubular structures. The cotton fibres vary in length from 20 mm to 40
mm and in width from 15 μm to 25 μm. The cotton fibres are separated and cleaned from the
seeds by a mechanical process called ‘ginning’.
Cotton fibres are basically cellulosic polymers. Raw unpurified cotton as such is hydrophobic
in nature, i.e. it does not absorb water, on the contrary it repels water. This hydrophobic
property of the cotton is due to the presence of non-cellulosic substances such as waxes,
pectins, proteins, etc. on the fibre. A typical chemical composition of cotton fibres is (%) :
cellulose, 94; waxes, 0.6; pectins, 0.9; protein, 1.3; mineral matters, 1.2; organic compounds
0.8; total sugars, 0.3.
Cotton is mainly used in textile for manufacturing fabric. However, cotton varieties such as
Bengal Desi or RG 8 are having fibre length less than 20 mm and generally are not suitable
for fabric making. Such short staple cotton could find alternative applications in the field of
biomedicines such as dressings, gauzes, bandages etc.
The basic raw material used for surgical cotton and dressings is the short staple raw cotton
fibres or the waste cotton fibres. The surgical cotton in biomedicine is used in three different
forms:
(a) Non-absorbent, bleached cotton
(b) Absorbent not bleached cotton
(c) Absorbent bleached cotton
For preparing absorbent cotton from native cotton, it is necessary to remove the noncellulosic
materials from the cotton. Conventionally, the absorbent cotton is made by treating
the cotton with alkali such as sodium hydroxide at boil and pressure. The process is called as
scouring process. In laboratory, the scouring is being done by treating cotton with 1.0%
NaOH 1:20 volume at 121° for 4 hr in an autoclave at a pressure of 15 Ib/in². The scoured
cotton is washed with water, 1% acetic acid and finally with water and dried.
Enzymes are biocatalysts and they bring about reactions under moderate conditions. In
textiles, many enzymes, such as amylase, cellulase, protease, pectinase, lipase find
applications. Enzymes such as lipase, cellulase, pectinase and protease could be used for
scouring of cotton and fabric.
A process has been developed at CIRCOT to make absorbent cotton from short staple cotton
using commercial pectinase preparation. The process consists of treating the Bengal Desi
with pectinase under optimum condition for 30 min, in the presence of wetting agent.
