(Trans) dermal insulin delivery based on polymeric systems

摘要

Diabetes is one of the leading lethal diseases, which is often treated by hypodermic injection of insulin or by oral delivery. Oral drug delivery systems show limitations due to poor absorption and degradation that occurs in the GI tract and in the liver. Due to the patient discomfort that leads to poor patient compliance, alternative methods to administer insulin are of great interest. In recent years, much attention has been paid to transdermal delivery devices because of drug delivery reliability to a target site with patient-friendly technologies. The major part of integumentary systems is skin, but skin drug delivery is challenging due to barrier properties exhibited by the outermost layer of skin stratum corneum. Transdermal drug delivery systems (TDDS) control the rate of release of the drug into the patient so that blood concentration maintains a steady state, and gastrointestinal absorption is avoidable. Controlled drug release causes minimum side effects and improves bioavailability of drugs, which showed poorly bioavailable drugs over other routes of delivery. The limiting factor in TDDS is stratum corneum, which is the outer layer of the skin and which acts as an effective barrier to the transport of biomolecules into the skin. For this reason, an effective method for drug delivery is hypodermic injection, which is a painful delivery. Besides, it needs a high level of expertise to administer the injection and the occasional risk of infections acquired through needle sticks. In recent year(')s microneedle (MN)-mediated drug delivery systems have been developed which can meet all the above goals. Microneedles are microscopic needles, which can deliver the drug to the target site by the degradation or dissolution of the polymer in the skin after insertion. This results in delivery of the encapsulated molecules, and no needles are left afterward. Microneedles are large and strong enough to insert into the skin and to deliver drugs into the skin, but they are short enough so that they do not reach the deeper layers of the skin to cause nerves stimulation. Microneedles offer an efficient and attractive method for delivering several classes of biomolecules and drugs to the skin in a self-administered manner. The overall goal of this research is TDDS and polymer micromodels system for insulin drug delivery, which can deliver an active biopharmaceutical in vivo for producing the desired physiological response.