Features of electron-microscopic visualization of soft phospholipid nanoparicles

Yu. E. Poletaeva; A. E. Grigor; I. S. Dovydenko; E. I. Ryabchikova

doi:10.20914/2310-1202-2017-4-191-196

Features of electron-microscopic visualization of soft phospholipid nanoparicles

Yu. E. Poletaeva, A. E. Grigor, I. S. Dovydenko, E. I. Ryabchikova

https://doi.org/10.20914/2310-1202-2017-4-191-196

Full Text:

PDF (Rus)

Generate QR code

Abstract

Transmission electron microscopy (EM) is the way to control structure of lipid nanoparticles. Our work was aimed at study of EM imaging of nanoparticles based on mixtures of dioleoylphosphatidylcholine (DOPE) and phosphatidyl acid (PA), and phosphatidylcholine (PC) and cholesterol (Chol), using contrasting with uranyl acetate (UA), and phospho-tungstic acid (PTA). Suspensions of nanoparticles DOPE/PA (9:2) and PC/Chol (1:1) were adsorbed on formvar film, 1 min, and contrasted with UA, or PTA (pH 0.5), or PTA (pH 7.0), 5-10 sec, then studied in EM Jem-1400 (Jeol, Japan). Spectra of 31P-NMR of samples were recorded on spectrometer AV-300 (Bruker, Germany). Nanoparticles DOPE/PA, UA and PTA (pH 0.5) contrasting: rounded particles, formed by filaments (2-3 nm) of low electron density (ED). Filament morphology corresponds to structures of inverted hexagonal phase (IHP). PTA (pH 7.0) contrasting leads to filament structuring and appearance of membrane-like structures, morphologically corresponding to lamellar phase (LP). However, 31Р-NMR analysis revealed in sample spectrum single signal on 0,189 m.d. (IHP). Nanoparticles PC/Chol, UA and PTA (pH 0.5) contrasting: irregular particles, formed by filaments (2 nm), low ED, corresponding to IHP. The PTA revealed stacks of lipid bilayers in preparation, corresponding to LP. Presence of lipid different phases is confirmed by 31Р-NMR: analysis of preparation spectra, showed LP (signal -0,482 M. D.), IHP and isotropic phase (signals on -0,235, -0,362 M. D.). Thus, EM allows to identify lipid phase state; “traditional” contrasting agents differently identify components in same preparation, suggesting their active interaction with lipid molecules, and indicates necessity of using different contrasting for visualization of lipid nanostructures.

Keywords

electron microscopy, negative staining, soft nanoparticles, phospholipids

УДК: 615.071

About the Authors

Yu. E. Poletaeva

Institution of chemical biology and fundamental medicine
Russian Federation
graduate student, group of microscopy, Lavrent’ev av. 8, Novosibirsk, 630090, Russia

A. E. Grigor

Institution of chemical biology and fundamental medicine
Cand. Sci. (Biol.), group of microscopy, Lavrent’ev av. 8, Novosibirsk, 630090, Russia

I. S. Dovydenko

Institution of chemical biology and fundamental medicine
Cand. Sci. (Chem.), lead engineer, laboratory of biomedical chemistry, Lavrent’ev av. 8, Novosibirsk, 630090, Russia

E. I. Ryabchikova

Institution of chemical biology and fundamental medicine
Dr Sci. (Biol.), professor, head of microscopy group, Lavrent’ev av. 8, Novosibirsk, 630090, Russia

References

1. Balazs D.A., Godbey W. Liposomes for use in gene delivery. J Drug Deliv. 2011. vol. 2011. pp. 326497. doi 10.1155/2011/326497

2. Jouhet J. Importance of the hexagonal lipid phase in biological membrane organization. Front Plant Sci. 2013. vol. 4. pp. 494. doi10.3389/fpls.2013.00494

3. Hope M.J. Enhancing siRNA delivery by employing lipid nanoparticles. Ther Deliv. 2014. vol. 5. no. 6. pp. 663–673. doi 10.4155/tde.14.37

4. Belletti D., Vandelli M.A., Tonelli M., Zapparoli M. et al. Functionalization of liposomes: microscopical methods for preformulative screening. J Liposome Res. 2015. vol. 25. no. 2. pp. 150–156. doi 10.3109/08982104.2014.956221

5. Hua H., Zhang N., Liu D., Song L. et al. Multifunctional gold nanorods and docetaxel-encapsulated liposomes for combined thermo – and chemotherapy. Int J Nanomedicine. 2017. vol. 12. pp. 7869–7884. doi 10.2147/IJN.S143977ijn12–7869 [pii]

6. Grigor’eva A.E., Dyrkheeva N.S., Bryzgunova O.E., Tamkovich S.N. et al. Contamination of exosome preparations, isolated from biological fluids. Biomedical Chemistry. 2017. vol. 63. no. 1. pp. 91–96. doi 10.18097/PBMC20176301091 (in Russian)

7. Lewis R.N., Mcelhaney R.N. Surface charge markedly attenuates the nonlamellar phase-forming propensities of lipid bilayer membranes: calorimetric and (31) P-nuclear magnetic resonance studies of mixtures of cationic, anionic, and zwitterionic lipids. Biophys J. 2000. vol. 79. no. 3. pp. 1455–1464. S0006–3495(00)76397–1 [pii] 10.1016/S0006–3495(00)76397–1

8. Dekker C.J., Geurts Van Kessel W.S., Klomp J.P., Pieters J. et al. Synthesis and polymorphic phase behaviour of polyunsaturated phosphatidylcholines and phosphatidylethanolamines. Chem Phys Lipids. 1983. vol. 33. no. 1. pp. 93–106. 0009–3084(83)90012–9 [pii]

9. Chao F.F., Blanchette-Mackie E.J., Chen Y.J., Dickens B.F. et al. Characterization of two unique cholesterol-rich lipid particles isolated from human atherosclerotic lesions. Am J Pathol. 1990. vol. 136. no. 1. pp. 169–179.

10. Pyshnaya I.A., Razum K.V., Dolodoev A.S., Shashkova V.V. et al. Surprises of electron microscopic imaging of proteins and polymers covering gold nanoparticles layer by layer. Colloids Surf B Biointerfaces. 2017. vol. 150. pp. 23–31 doi S0927–7765(16)30783–4 [pii] 10.1016/j.colsurfb.2016.11.007

Review

For citations:

Poletaeva Yu.E., Grigor A.E., Dovydenko I.S., Ryabchikova E.I. Features of electron-microscopic visualization of soft phospholipid nanoparicles. Proceedings of the Voronezh State University of Engineering Technologies. 2017;79(4):191-196. (In Russ.) https://doi.org/10.20914/2310-1202-2017-4-191-196

This work is licensed under a Creative Commons Attribution 4.0 License.

ISSN 2226-910X (Print)
ISSN 2310-1202 (Online)

Username
Password
	Remember me
Not a user? Register with this site Forgot your password?

User

Proceedings of the Voronezh State University of Engineering Technologies