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The Chromatogram Series: PLGA

22 August 2013 No Comment

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This chromatogram shows poly(lactic-co-glycolic acid) or PLGA. It is a promising copolymer for controlled drug release in polymer-drug conjugates.

Solvent Acetone
Flow Rate [mL/min] 1.00
Column Set 3 x I-OLIGO-3078
Column Temp (°C) 30.0
Injection volume μL 150.0
Concentration [mg/mL] 31.09
Mw Weight Average [Da] 3,669
Sample dn/dc [mL/g] 0.095
Sample IV [dL/g] 0.119
Chromatogram of poly-lactic-co-glycolic acid

Chromatogram of poly(lactic-co-glycolic acid) PLGA. Refractive index RI, Viscometer, Right angle light scattering RALS shown versus elution volume.


PLGA is a common bio-polymer used for various pharmaceutical applications including drug delivery and conjugates. PLGA can be dissolved in tetrahydrofuran (THF), acetone or ethyl acetate. Because this sample shown here is a low molecular weight PLGA, the Solvent Enhanced Light Scattering (SELS) method was used to improve the LS signal which is very poor in THF.
The 90º (RALS) light scattering data are clean with the low dn/dc and low molecular weight. Note the comparatively high injection concentration necessary to achieve good separation of peak from baseline.


If you have any questions, please email me at ulf.nobbmann@malvern.com. Thanks!