Abstract
Purpose. The main purpose of the present study was to investigate submicron emulsions as potential oligonucleotide (ON) delivery system.
Methods. Submicron emulsions containing various concentrations of stearylamine (SA) were prepared by microfluidization. After association with model oligothymidylates, these emulsions were characterized in terms of particle size, ζ-potential, association efficiency and release upon dilution. The interactions between ON and SA were investigated by partitioning studies between water and oily phases, with ON of three different lengths (pdT16, pdT30, pdT50). The stability of pdT16 in the presence of nucleases was evaluated by incubation in cell culture medium supplemented with 10% of foetal calf serum.
Results. The ON association efficiency was much higher with emulsions containing SA (ESA) than with control emulsions (E0), whatever the ON length. In addition, ESA was shown to protect ON against degradation for up to 3 hours in culture medium. ON and SA were able to form ion-pairs and the resulting complex was found to be insoluble both in water and in oil. Zeta potential was maintained constant when increasing the ON concentration, until flocculation occurred (up to 250μM in the case of pdT16 for example). This has been explained by the presence of SA in excess, soluble in the oily core of droplets, able to migrate towards the interface and replacing SA neutralized in ion-pairs.
Conclusions. ESA appears to be a valuable system for delivery of ON and might even be improved by selecting an oily phase in which the SA/ON complex would be soluble.
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REFERENCES
Y. Rojanasakul. Antisense oligonucleotide therapeutics: drug delivery and targeting. Adv. Drug Del. Rev. 18:115–131 (1996).
A. Thierry, A. Rahman, and A. Dritschilo. Overcoming multidrug resistance in human tumor cells using free and liposomally encapsulated antisense oligodeoxynucleotides. Biochem. Biophy. Res. Com. 190:952–960 (1993).
C. Chavany, T. Saison-Behmoaras, T. Le Doan F. Puisieux, P. Couvreur, and C. Hélène. Adsorption of oligonucleotides onto polyisohexylcyanoacrylate nanoparticles protects them against nucleases and increases their cellular uptake. Pharm. Res. 11:1370–1378 (1994).
C. Emile, D. Bazile, F. Herman, C. Hélène, and M. Veillard. Encapsulation of oligonucleotides in stealth Me.PEG-PLA50 nanoparticles by complexation with structured oligopeptides. Drug Delivery 3:187–195 (1996).
O. Zelphati and F. C. Szoka Jr. Intracellular distribution and mechanism of delivery of oligonucleotides mediated by cationic lipids. Pharm. Res. 13:1367–1372 (1996).
K. Lappalainen, A. Urtti, E. Söderling, I. Jääskeläinen, K. Syrjänen, and S. Syrjänen. Cationic liposomes improve stability and intracellular delivery of antisense oligonucleotides into CaSki cells. Biochim. Biophys. Acta 1196:201–208 (1994).
D. C. Litzinger, J. M. Brown, I. Wala, S. A. Kaufman, G. Y. Van, C. L. Farrel, and D. Collins. Fate of cationic liposomes and their complex with oligonucleotide in vivo. Biochim. Biophys. Acta 1281:139–149 (1996).
E. Elbaz, A. Zeevi, S. Klang, and S. Benita. Positively charged submicron emulsions—a new type of colloidal drug carrier. Int. J. Pharm. 96:R1–R6 (1993).
S. Klang, J. Frucht-Pery, A. Hoffman, and S. Benita. Physicochemical characterization and acute toxicity evaluation of a positively-charged submicron emulsion vehicle. J. Pharm. Pharmacol. 46:986–993 (1994).
I. Aynié, C. Vauthier, M. Foulquier, C. Malvy, E. Fattal, and P. Couvreur. Development of a quantitative polyacrylamide gel electrophoresis analysis using a multichannel radioactivity counter for the evaluation of oligonucleotide-bound drug carrier. Anal. Biochem. 240:202–209 (1996).
D. Korner, S. Benita, G. Albrecht, and A. Baszkin. Surface properties of mixed phospholipid-stearylamine monolayers and their interaction with a non-ionic surfactant (poloxamer). Colloids Surfaces 3:101–109 (1994).
M. Berton, S. Sixou, R. Kravtzoff, C. Dartigues, L. Imbertie, C. Allal, and G. Favre. Improved oligonucleotide uptake and stability by a new drug carrier, the supramolecular biovector. Biochim. Biophys. Acta 1355:7–19 (1997).
F. M. P. Wong, D. L. Reiner, and M. B. Bally. Cationic lipid binding to DNA: characterization of complex formation. Biochem. 35:5756–5763 (1996).
E. Fattal, C. Vauthier, I. Aynie, Y. Nakada, G. Lambert, C. Malvy, and P. Couvreur. Biodegradable polyalkylcyanoacrylate nanoparticles for the delivery of oligonucleotides. J. Control. Rel. In press.
T. Hara, F. Liu, D. Liu, and L. Huang. Emulsion formulations as a vector for gene delivery in vitro and in vivo. Adv. Drug Del. Rev. 24:265–271 (1997).
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Affiliated with the David R. Bloom Center for Pharmacy at the Hebrew University of Jerusalem.
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Teixeira, H., Dubernet, C., Puisieux, F. et al. Submicron Cationic Emulsions as a New Delivery System for Oligonucleotides. Pharm Res 16, 30–36 (1999). https://doi.org/10.1023/A:1018806425667
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DOI: https://doi.org/10.1023/A:1018806425667