FABRICS

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					Faculty of Pharmacy,PUA
Forensic Rharmacognocy PHR 446


                                 FABRICS
                                 Origin of Fabrics

Vegetable:

Hairs: ex. Cotton                   Fibers: ex.Flax and Jute

Animal:

Hairs: ex.Wool                     Fibers: ex.Silk

Regenerated:

Ex.Viscose

Synthetic:

Ex.Nylon

Differences between hair and Fibers:

                            HAIR‫أ‬                              FIBER
Covering       From the outside                      From the inside


Comes          Epidermis                             Supportive Tissue
from
Faculty of Pharmacy,PUA
Forensic Rharmacognocy PHR 446




                        1-Fabrics of Vegetable Origin

                                     a)Cotton

   Point of               RAW COTTON                       ABSORBANT COTTON
 Comparison
    Origin      It consists of the hairs covering the seeds of Gossypium barbadense
                and other species of Gossypium f.Malvaceae
 Description    Loose mass of delicate filaments, Same, BUT white in color due
                with a slightly brownish tint.         to chemical treatment 'removal
                                                       of cuticle'
Microscopical   Drawing:                               Drawing:
Examination
 (mount in
   water)




                                                      Description:
                Description:                          Same, BUT less twisting due to
                The hairs are unicellular, flat, with method of preparation.
                thin cellulosic walls, with blunt or N.B it's prepared from cotton
                rounded apex and they are             waste i.e hairs which were
                twisted over each other.              rejected by certain machinery
                                                      during spinning process.
Chemical Test   a)test for carbohydrates:
                1-molish's test: Violet Ring
                2-test for cellulose: Bluish Violet color

                3-cuoxam test (ammonical solution of CuCO3):

                 For RAW COTTON:
                The hairs are rapidly swollen showing balloon like structure with
                constricted rings of cuticle bands, and then the walls gradually
                dissolve.

                Explanation: not the whole hair is covered with cuticle equally so
                there are naked areas; these areas are more permeable so they
                swell. While at the other parts the non-elastic cuticle doesn't swell
                appearing to form constricted bands.
Faculty of Pharmacy,PUA
Forensic Rharmacognocy PHR 446


                For ABSORBANT COTTON:
                 The Hairs are evenly swollen and finally dissolve 'due to absence of
                cuticle'.


                b)test for proteins:
                1-millon'sreagent: -ve
                2-picric acid reagent: -ve
                3-I2 reagent: -ve

                c)flame test: odor of burnt paper due to evolution of CO2
                'fumes with solid residue, acidic to litmus paper'


Constituents    91% cellulose                        Almost pure cellulose
                Wax, oil, cellular content,          6-7% moisture
                cytoplasm, protoplasm
                7-8% moisture
    Uses        1-In filtration
                2-Surgical dressing
                3-Insulating material
                4-fabrics and textile.
Faculty of Pharmacy,PUA
Forensic Rharmacognocy PHR 446




                                 b)Flax and Jute
   Point of Comparison                FLAX                          JUTE
          Origin            It consists of strands of    It consists of liginified
                            non-lignified pericyclic     phloem fibers of the stem
                            fibers from the stem of      of Corchorus olitorus and
                            Linum usitatissimum          other species of Corchorus
                            f.Linaceae                   f.Tiliaceae.
       Description          Strands of fibers, silvery   Strands are pale buff or
                            yellow in color, rough       silvery grey, coarse
                            texture and they have        texture.
                            more tensile texture than
                            cotton.
      Microscopical         Drawing:                     Drawing:
      Examination




                                                         Description:
                            Description:
                            Each strand consists of a
                            bundle (5-20 fibers)
                            interlocked.
                            FIBERS ARE:
                            1-long with faint
                            longitudinally striated      1-un-equal lignified
                            thick walls.                 thickening.
                            2-narrow lumen.              2-non-uniform lumen.
                            3-pointed ends showing       3-rounded apex.
                            transverse lines crossing
                            over one another due to
                            beating of the fibers
Faculty of Pharmacy,PUA
Forensic Rharmacognocy PHR 446

                            during preparation.
      Chemical Test         a)test for carbohydrates:
                            1-molish's test: violet
                            color
                            2-test for cellulose: blue
                            (cellulose)                     Brownish yellow
                            3-cuoxam test:
                            Uniform swelling and the
                            lumen acquires vermiform        Dissolves after some time.
                            appearance which
                            dissolves after time.

                            b)test for protein:
                            1-millon's reagent: -ve
                            2-picric acid reagent: -ve
                                                            Same
                            3-iodine: -ve

                            c)flame test: odor of
                            burnt paper with the            Same
                            evolution of CO2 'acidic to
                            litmus paper'.

                            CONFIRMATORY
                            TEST
                            (test for lignin):
                            phloroglucinol+ HCL
                             No red color 'not lignified'   Red color 'lignified'


      Constituents          Pectocellulose(         53% cellulose
                            pectose + cellulose )   22% hemicelluloses
                            Galactose, uronic acid. 11% lignin
                                                    1% waxes
          Uses              1-manufacturing of      1-straining media (to
                            lint                    soak up fluids)
                            2-linen-cloth           2-making sacs and
                            3-filtering media       coarse bags.
                                                    3-manufacturing of
                                                    medical toes.
                                                    4- Surgical pads and
                                                    splints.
Faculty of Pharmacy,PUA
Forensic Rharmacognocy PHR 446

				
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