Nanocarriers Protecting Toward an Intestinal pre-uptake Metabolism

Abstract

Pre-uptake metabolism within the GI tract is responsible for the poor oral bioavailability of numerous drugs. As nanocarriers function as a 'shield', protecting incorporated drugs from enzymatic attack, there is an increasing interest in utilizing them as a tool for overcoming drug degradation. Degradation of carriers resulting in the release of incorporated drugs, mucus permeation, enzyme inhibitory properties and their toxicity are crucial factors that must be taken into account when designing proper nanocarriers. The use of polymer- and lipid-based nanocarriers as protective vehicles are discussed within this review. Lipid-based carriers and novel mucopenetrating particles seem to have a great potential in avoiding metabolizing enzymes. Accordingly, nanocarriers are promising tools for improving the bioavailability of drugs, being sensitive to a pre-uptake metabolism.

Solid lipid nanoparticles delivering anti-inflammatory drugs to treat inflammatory bowel disease: Effects in anin vivomodel

“…Since drugs encounter a harmful environment after oral administration, high doses and/or frequent administration are usual to counter the degradation by stomach acidic pH or small intestine digestive enzymes; on the other hand, the occurrence of side effects are more likely[11,47]. In particular, SLN have been one of most studied carriers worldwide for drug delivery, since this nanosystem is mainly composed of solid lipid core and lecithin, has very low toxicity profile, good affinity for biological membrane, ability to facilitate up-taking/overcoming, and capacity to improve drug pharmacokinetics[48,49]. …”

Self-emulsifying drug delivery system: Mucus permeation and innovative quantification technologies

“…This unique formation mechanism makes these systems highly suitable for oral delivery. A further convincing reason for suitability of SEDDS for oral nano-delivery is that the preparation of these systems do not require sluggish size reduction techniques associated with other nanosystems [91]. For oral administration of SEDDS, the combination of oils and surfactants are generally administered via a gastroresistant capsular system so that the acidic barrier of the stomach can be avoided.…”

Sistemas de entrega de fármacos autoemulsificables: una plataforma de desarrollo alternativa para la industria farmacéutica colombiana

“…Un aspecto importante a considerar al desarrollar sistemas de entregas de fármacos es el medio al cual estará expuesto y las barreras fisiológicas (fluidos intestinales, mucosas, el epitelio intestinal etc.) que deben superar luego de la ingestión [41,42]. Algunos excipientes utilizados en los sistemas lipídicos son susceptibles a los procesos de degradación enzimática que tienen lugar en el tracto gastrointestinal, por lo cual recientemente ha existido un interés por una mejor comprensión de los complejos procesos involucrados en la digestión de lípidos, ya que esta puede afectar la solubilidad, dispersión y biodisponibilidad de los fármacos pocos solubles en agua [35].…”