The system with zwitterionic lactose-based surfactant for complexation and delivery of small interfering ribonucleic acid—A structural and spectroscopic study

Abstract

Systems suitable for the effective preparation of complexes with siRNA (small interfering RNA) are at the center of interest in the area of research work on the delivery of the RNA-based drugs (RNA-therapeutics). This article presents results of a study on the structural effects associated with siRNA complexation by a surfactant comprising a lactose group (N-(3-propanesulfone)-N-dodecyl-amino-beta-D-lactose hydrochloride, LA12). The double stranded siRNA oligomer (21 base pairs) used in this study is responsible for silencing a gene that can be important in the therapy of myotonic dystrophy type 1. The obtained siRNA/LA12 lipoplexes were studied using the methods of small angle scattering of synchrotron radiation, circular dichroism spectroscopy, Fourier transform infrared spectroscopy, and electrophoretic mobility tests. Lipoplexes form in solution stable lamellar or cubic phases. The surfactant selected for the study shows much lower cytotoxicity and good complexation abilities of siRNA than dicationic or polycationic surfactants.

Lactose-based surfactants complexable with oligonucleic acids as gene delivery agents

“…This study provides an extension of our previous preliminary investigations on complexation of one lactose-based surfactant with siRNA [8]. The main aim of this study was to determine the effect of increasing concentration of lactose-based zwitterionic surfactant in aqueous solution on the conformation of short single-and double-stranded nucleic acids and to determine the structure of these lipoplexes.…”

“…Two surfactants showing unique properties were chosen for the study: N-(3propanesulfonate)-N-dodecyl-lactoside ammonium hydrochloride (LA12) and N-(3propanesulfonate)-N-tetradecyl-lactoside ammonium hydrochloride (LA14). The LA12 surfactant has been previously examined by us but only in combination with siRNA [8], while this study is devoted to its application in the complexation of dsDNA and ssDNA.…”

“…In our previous work, we showed that for the lowest three concentrations of LA12 (p/n = 1, 2 or 4) in the system with siRNA, a single lamellar phase is formed (d 001 = 3.17 nm), which is also observed for pure surfactant and for the systems of LA12 with dsDNA (Fig 4a). In the systems with higher LA12 concentrations (p/n = 8, 10 or 16), the presence of coexisting lamellar phases of d 001 =3.28 nm and d 001 =3.17 nm is observed, both for pure surfactant and its complexes with DNA at the same concentrations 8…”

“…Changes in the conformation of double-stranded RNA (siRNA) induced by the presence of the LA14 surfactant in the system were found on the basis of analysis of the CD spectra obtained for their complexes (see Fig 6). Our earlier studies on complexation in the siRNA/LA12 system [8] were taken into account in the interpretation of the obtained results. For the complexes of siRNA with the LA14 surfactant (with a longer alkyl chain compared to LA12), the changes observed in the CD spectrum and electrophoretic pattern (Fig 6a) are similar to those observed for siRNA complexes with LA12 [8].…”

“…Our earlier studies on complexation in the siRNA/LA12 system [8] were taken into account in the interpretation of the obtained results. For the complexes of siRNA with the LA14 surfactant (with a longer alkyl chain compared to LA12), the changes observed in the CD spectrum and electrophoretic pattern (Fig 6a) are similar to those observed for siRNA complexes with LA12 [8]. Taking into account the results obtained for LA12 and its complexes with siRNA, it was found that the A-RNA form of the nucleic acid is formed in the complex with LA14 at 40 mM surfactant concentration.…”