Synthesis of Cholic Acid-Peptide Conjugates With A Negatively Charged Ester Linkage for Oral Delivery

Advances in biotechnology have provided a wide range of therapeutically active and commercially available biologic large molecules as protein and peptide drugs. However, oral administration of these drugs has been highly limited due to the stability and the difficulties to cross the gastrointestinal membrane. Significant research attempts have been made in recent years to utilize carrier-mediated transport systems for enhancement in the oral bioavailability. Among various intestinal transporters, the intestinal bile acid transporter has a good potential because of its higher capacity and low structural selectivity. The transport system facilitates the daily absorption of 10-20 g bile salts at a more than 95% efficiency rate. 

The system also tolerates significant chemical modifications at the C3 and C24 positions of the sterol nucleus. Thus, the intestinal bile acid transporter has been specifically investigated for its ability to increase the oral absorption of cholic acid conjugates of proteins and small peptides through the carrier-mediated transport mechanism. The fact that the bile acid transporter tolerates the chemical modifications of cholic acid provides a solid rationale for the development of a cholic acid-peptide conjugate for enhanced oral absorption.

Formulation of Catechin Hydrate Nanocapsule and Study of its Bioavailability

Drug delivery refers to approaches, formulations, technologies, and systems for transporting a pharmaceutical compound in the body as needed to safely achieve its desired therapeutic effect. It may involve scientific site targeting within the body, and also facilitating systemic pharmacokinetics; in any case, it is typically concerned with both quantity and duration of drug’s persistence in the system. Drug delivery is often executedvia a drug’s chemical formulation alone, but it may also involve in drug-devicecombination products. Drug delivery is a concept where much emphasis should be given to dosage form and route of administration.

The choice of the delivery systems is to allow the safe application of the drug with minimum losses. This suggests that the drug in theformulation must be chemically, physically and microbiologically stable. Side-effects of the drug and drug interactions should be avoided or minimized by the use of suitable drug delivery systems.