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PubMed · 11102674

Two methods for quantifying DNA extracted from poly(lactide-co-glycolide) microspheres.

S P Barman·L Lunsford·P Chambers·M L Hedley
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Abstract

DNA can be formulated with synthetic polymers such as poly(lactide-co-glycolide) (PLG) to generate microparticles. Researchers have used either UV spectroscopy or fluorometry with PicoGreen((R)) dye to quantify PLG-encapsulated DNA. While the sensitivity of DNA detection and quantification by PicoGreen is higher ( approximately 12 pg/ml) compared to UV ( approximately 0.5 microg/ml), each method as an analytical tool has limitations. The premise of this work addresses the usefulness and limitations of each method to determine encapsulation efficiencies in PLG microspheres post-process, and to quantify release of DNA from microspheres during in vitro release experiments. In addition, assay conditions for accurate and reproducible extraction of DNA from PLG microspheres using a biphasic (aqueous/organic) solvent system are described. It was also determined that residual poly(vinyl alcohol) and DNA isoforms (linear, nicked, supercoiled) affected PicoGreen/DNA fluorescence values.

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DNALactic AcidMicrospheresPlasmidsPolyglycolic AcidPolylactic Acid-Polyglycolic Acid CopolymerPolymersPolyvinyl AlcoholJournal Article

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S P Barman, L Lunsford, P Chambers, M L Hedley. 2000-12-03. Two methods for quantifying DNA extracted from poly(lactide-co-glycolide) microspheres.. https://doi.org/10.1016/s0168-3659(00)00308-4

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