CYCLODEXTRIN AND WOOL

The effects of cyclodextrin on wool can be a difficult problem for your client and for
you. Wool is a complex structure, Its outermost layer is called the F-layer, it is a lipid
layer, which is on top of the epicuticle. The F-layer and the epicuticle provide
protection by way of water repellency, stain resistance and a durable wear surface.
Inside the wool fiber itself is the cell membrane complex, which is also a lipid based
membrane that provides adhesion between the fiber cells. It is the only continuous
phase in the wool fiber. These lipid-based materials help to make wool a high performance
and long lasting textile fiber.

A cyclodextrin molecule is a round, funnel shaped structure made up of glucose
(sugar) molecules. They are used in food, agriculture, pharmaceutical and chemical
industries. What is interesting about this funnel shaped cyclodextrin molecule is that
the outside of the molecule surface is hydrophilic and the inside cavity surface is
hydrophobic. This gives the molecule a split personality, it both loves water (on the
outside) and hates water (on the inside). Conversely, it loves lipids (on the inside) and
hates lipids (on the outside).

When cyclodextrin comes into contact with other molecules, it can often physically
encapsulate them within its cavity. This entrapment process can, and does work well
on odors, preventing the odor molecules from being released into the air, and
reaching our noses, affectively, reducing or eliminating the odors. It makes sense that
cyclodextrin is in over-the-counter deodorizers like Febreze. You should be aware of
the widespread use of cyclodextrin. Febreze sales are over $1 billion annually. Due to
this unique molecular structure, cyclodextrin can interact with various substances,
including lipids.

When cyclodextrin is applied to wool, their interactions with the lipid based
components of the wool can be damaged. It is capable of extracting lipids from the
cell membranes. This leads to the breakdown of the F-layer and more important, the
cell membrane complex, causing severe damage overtime. This can result in a loss of
strength, resiliency, and overall quality of the wool fibers. You can see and feel this
damage, plus you can often smell the deodorizer too. You can and should repair this
damage.

Here are some recommendations:

1. Avoid frequent use. If you have wool rugs or clothing, avoid using cyclodextrinbased
chemicals repeatedly.
2. Spot cleaning. We recommend using LST or a wool specific cleaner that will not
further harm the wool and does not cause resoiling.
3, Immersion wash away cyclodextrin residues. Use LST solution to thoroughly wash
and rinse away residues.
4. Repair. Apply Wool Rug Revitalizer to restore the missing lipids and to revitalize the
damaged wool fibers (see Wool Rug Revitalizer below).

Sources:

Wool its chemistry and physics by Peter Alexander and Robert Hudson.

Cochlear spiral ganglion neuron degeneration following cyclodextrin induced hearing
loss by Dalian Ding, Haiyan Jing and Richard Salvi.

Hearing loss and hair cell death in mice given the cholesterol-chelating agent,
hydroxy propyl-B-cyclodextrin by Mark a. Crumling, Liqian Liu, Paul V. Thomas,
Jennifer Benson, Ariane Kanicki, Lisa Kabara, Karin Halsey, David Dolan and R. Keith
Duncan.