Manufacturing of a Secretoneurin Drug Delivery System with Self-Assembled Protamine Nanoparticles by Titration.
Since therapeutic peptides and oligonucleotides are gathering interests as active pharmaceutical ingredients (APIs), nanoparticulate drug delivery systems are becoming of great importance. Thereby, the possibility to design drug delivery systems according to the therapeutic needs of APIs enhances clinical implementation. Over the last years, the focus of our group was laid on protamine-oligonucleotide-nanoparticles (so called proticles), however, the possibility to modify the size, zeta potential or loading efficiencies was limited. Therefore, at the present study we integrated a stepwise addition of protamine (titration) into the formation process of proticles loaded with the angiogenic neuropeptide secretoneurin (SN). A particle size around 130 nm was determined when proticles were assembled by the commonly used protamine addition at once. Through application of the protamine titration process it was possible to modify and adjust the particle size between approx. 120 and 1200 nm (dependent on mass ratio) without influencing the SN loading capacity. Dynamic light scattering pointed out that the difference in particle size was most probably the result of a secondary aggregation. Initially-formed particles of early stages in the titration process aggregated towards bigger assemblies. Atomic-force-microscopy images also revealed differences in morphology along with different particle size. In contrast, the SN loading was only influenced by the applied mass ratio, where a slight saturation effect was observable. Up to 65% of deployed SN could be imbedded into the proticle matrix. An in-vivo biodistribution study (i.m.) showed a retarded distribution of SN from the site of injection after the application of a SN-proticle formulation. Further, it was demonstrated that SN loaded proticles can be successfully freeze-dried and resuspended afterwards. To conclude, the integration of the protamine titration process offers new possibilities for the formulation of proticles in order to address key parameters of drug delivery systems as size, API loading or modified drug release.
Department of Pharmaceutical Technology, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria.
Bernhard
B
Scheicher
Department of Pharmaceutical Technology, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria.
Cornelia
C
Lorenzer
Department of Pharmaceutical Technology, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria.
Katrin
K
Gegenbauer
Department of Pharmaceutical Technology, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria.
Julia
J
Partlic
piCHEM, Kahngasse 20, Graz, Austria.
Fritz
F
Andreae
Department of Internal Medicine, Clinical Division of Nephrology, Medical University of Graz, Auenbruggerplatz 27, Graz, Austria.
Alexander H
AH
Kirsch
Department of Internal Medicine, Clinical Division of Nephrology, Medical University of Graz, Auenbruggerplatz 27, Graz, Austria.
Alexander R
AR
Rosenkranz
Department of Pharmaceutical Technology, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria.
Oliver
O
Werzer
Department of Pharmaceutical Technology, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria.
Andreas
http://orcid.org/0000-0003-3127-287X
A
Zimmer
D000818:Animals; D002232:Carbocyanines / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods; D016503:Drug Delivery Systems / Q000379:methods*; D008810:Mice, Inbred C57BL; D018625:Microscopy, Atomic Force; D053758:Nanoparticles / Q000737:chemistry*; D009479:Neuropeptides / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D009841:Oligonucleotides / Q000737:chemistry*; D010316:Particle Size; D011479:Protamines / Q000737:chemistry*; D053381:Secretogranin II / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D014018:Tissue Distribution
C569686:Alexa Fluor 647; D002232:Carbocyanines; D009479:Neuropeptides; D009841:Oligonucleotides; D011479:Protamines; D053381:Secretogranin II; C081159:secretoneurin