Fig. 3.

a In vitro release profile of protein from PLG microspheres carrying native or PEGylated IFN (IFN-mPEG₂₀₀₀ and IFN-mPEG₅₀₀₀) as shown with closed circle, inverted closed triangle, and open circle, respectively [replotted from (15), p. 111, Copyright (2003), with permission from Elsevier]. For the IFN study, 50:50 PLG microspheres had an average size of 1.8, 1.2, and 1.5 μm for those containing IFN, IFN-mPEG₂₀₀₀, and IFN-mPEG₅₀₀₀, respectively (15). b RNase A (filled squares), mono-PEG-RNase A (open triangles), and di-PEG-RNase A (filled circles) release from 85:15 PLG microspheres [replotted from (16), p. 866, Copyright (2005), with permission from John Wiley & Sons, Inc.]. In the RNase A study, 85:15 PLG microspheres, with a broad distribution of diameters ranging from 5 to 50 μm, were used (16)