Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1997-3-6
pubmed:abstractText
We characterized a glucose-sensitive, controlled-release insulin delivery system. Insulin release rates increased when glucose was perfused in the release media surrounding the matrix. The system was composed of solid, particulate insulin, incorporated into an ethylene-vinyl acetate copolymer (EVAc) matrix. Feedback control was mediated by the glucose oxidase enzyme immobilized to Sepharose beads, which were incorporated along with insulin into the EVAc matrix. When glucose in solution entered the insulin delivery system, gluconic acid was produced, causing a drop in the microenvironmental pH of the matrix. This fall in pH resulted in a rise in insulin solubility and consequently a rise in the insulin release rate from the matrix. Insulin concentrations increased in vitro and in vivo in response to glucose infusion. The increased insulin release was shown to consist of a finite pulse of insulin that required an optimal recovery period of 1 h to achieve a maximal repeated response to a glucose stimulus. Repeated pulses were demonstrated over a 4 h period. An optimum enzyme ratio was also determined.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-3549
pubmed:author
pubmed:issnType
Print
pubmed:volume
85
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1341-5
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Characterization of glucose-mediated insulin release from implantable polymers.
pubmed:affiliation
Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge 02139, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't