Open Access Peer-reviewed Review

Developments in encapsulation of insulin: Is oral delivery now possible?

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Submitted   Jul 8, 2019
Published   Aug 13, 2019
Issue    Vol 1 No 2 (2019)
DOI   10.25082/JPBR.2019.02.005

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Anubhav Pratap Singh corresponding author
Food Nutrition and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, Canada
Yigong Guo
Food Nutrition and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, Canada
Anika Singh
Food Nutrition and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, Canada
Wen Xie
Food Nutrition and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, Canada
Patrick Jiang
Food Nutrition and Health Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, Canada

Abstract

This review presents the possibilities of oral delivery of insulin. Insulin, being readily destroyed/ transformed by the proteolytic enzymes and first-pass effects in the digestive system, has mainly been administered through injection, such as intravenous injection and transdermal injection. With developments in the material sciences, appropriate encapsulation methodologies have been developed that could be employed to protect insulin from the digestive effects of the human GI system, and thereby have opened a gateway of research exploring the oral route of insulin delivery. One approach is to incorporate insulin into an emulsion with an appropriate oil-phase, which protects the insulin from degradation. Coating with natural or synthetic polymeric materials, or with lipids, followed by size-reduction to 100-1000 nm is applied as another common approaches of insulin encapsulation. Other approaches like liposomes, nanogels, etc. are also being explored. This review gives a summary of methods of preparation as well as in vitro and in vivo bioavailability of insulin through these methods. It is observed that the oral bioavailability of insulin intake has increased from about 0.1% to about 20% for encapsulated insulin.

Keywords
insulin, oral delivery, encapsulation, materials

Article Details

How to Cite
Singh, A. P., Guo, Y., Singh, A., Xie, W., & Jiang, P. (2019). Developments in encapsulation of insulin: Is oral delivery now possible?. Journal of Pharmaceutical and Biopharmaceutical Research, 1(2), 74-92. https://doi.org/10.25082/JPBR.2019.02.005
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This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

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