Conversion of a DNA chip to a nanocapsule array was performed by grafting on a liposome an oligonucleotide complementary to an oligonucleotide bound to the array. Each liposome may be loaded by a soluble molecule or may present a hydrophobic or amphiphilic molecule inserted in its wall. To detect liposomes on the chip, we used fluorescent dyes encapsulated in the liposome internal volume or fluorescent lipids.
View Article and Find Full Text PDFBiosens Bioelectron
October 2004
Enzymes are considered as providential molecules for biosensor design because of their sensitivity and the high specificity of the reactions they catalyse. However, their active sites often display low selectivity, a lot of molecules may enter and interfere with catalysis. These molecules may be either competitive inhibitors, activators or molecules which change the physico-chemical environment of the enzyme (pH, ionic strength).
View Article and Find Full Text PDFArtif Cells Blood Substit Immobil Biotechnol
February 2004
Enzyme encapsulation into liposomes is a promising technique to stabilize and prevent them from denaturation and proteolysis. We demonstrate this using acetylcholinesterase which is the main target for pesticides. In order to achieve a reasonable encapsulation yield, we analyzed the parameters involved in each step of various encapsulation procedures.
View Article and Find Full Text PDFBackground: We investigated the encapsulation mechanism of enzymes into liposomes. The existing protocols to achieve high encapsulation efficiencies are basically optimized for chemically stable molecules. Enzymes, however, are fragile and encapsulation requires in addition the preservation of their functionality.
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