Z. Huang et al. / International Journal of Pharmaceutics 427 (2012) 64–70
69
Table 2
NLPa containing different percentage of PEG-lipid.
PEG-lipid (mole%)
Sampleb
10
6
3
1.5
A
0.5
A
0.1
A
A
D
A
D
A
D
D
D
D
NLP diameter (nm)
57.7
87.0
3.5E2
67.7
84.8
2.0E5
60.3
91.5
5.6E3
73.9
89.0
6.8E5
74.7
95.8
1.6E5
126.2
91.0
1.2E6
85.2
96.6
4.5E5
146.7
88.0
3.3E7
93.6
96.3
1.5E7
194.1
81.4
1.1E9
93.3
97.1
2.4E8
213.7
89.3
1.3E9
DNA encapsulation ratio (%)c
Relative luciferase activity (RLU/mg protein)
a
NLP composition: x %PEG-DSPE, 50% TCL1, (50 − x) % APC22 or DOPE with 2.5 mole total lipids. Charge ratio 3/1 (+/−).
A: APC22; D: DOPE. All data are based on triplicate measurements.
DNA encapsulation ratio was determined by Picogreen assay.
b
c
Acknowledgments
This work was supported by NIH EB003008. Thanks are also
extended to the UCSF Mass Spectrometry Facility (A.L. Burlingame,
Director) supported by NIH NCRR RR01614.
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