Controlled release of borneol from nano-fibrous poly(L-lactic acid)/ cellulose acetate butyrate membrane

Borneol, one of the commonly used Chinese medicines, can be used to treat many diseases. The main ingredient of natural borneol is d-borneol extracted from the volatile oil of dipterocarp trees. Numerous studies have proved the effectiveness of borneol. It has been widely used in relieving symptoms of anxiety, fatigue and insomnia; inducing anaesthesia and analgesia to alleviate abdominal pain, wounds and burns; relieving rheumatic pain, hemorrhoids, skin diseases and ulcerations of the mouth, ears, eyes or nose; treating sore throats and skin infections; and is mainly used to treat cardiovascular and cerebrovascular diseases. Although borneol has a significant therapeutic effect, its easy sublimation and low water absorbability make it difficult to control the efficiency of delivery and decrease its function in connecting to various applications in the needs of modern society. Electrospun nanofiber has been commonly used as a delivery vehicle for various medicines for biomedical applications. Poly(L-lactic acid) and cellulose acetate butyrate (CAB) nano-fibrous nonwoven membranes were electrospun and used as drug carriers for borneol. To load borneol into a PLLA/CAB composite membrane, borneol/acetone solution was sprayed on PLLA/CAB fibers. While part of the CAB was dissolved by acetone, borneol was combined with CAB by hydrogen bonds between hydroxyl and carbanyl groups. PLLA still kept a porous morphology of the whole drug-loaded membrane since it does dissolve in acetone. This structure provided a high quality and stable drug delivery system. With adjustable drug release properties, PLLA/CAB nano-fibrous composite nonwoven membranes can be alternative candidates for developing novel external medical textiles.