A seam sealant, such as Fray Check from Prym Dritz, is glue-like liquid used to secure the edges of the fabric and stop fraying.
This product can be used on any embroidery fabric, dries clear, and is both machine washable and dry cleanable. However, it because Fray check is a nylon plastic in an alcohol base, it can be removed using rubbing alcohol.
To use, apply a thin ling of sealant along the edge of the fabric and allow to dry completely.
On dark or silky fabrics, the seam sealant may be noticable after it dries, so be sure to check in an inconspicuous area before using.