Freeze-drying of HI-6-loaded recombinant human serum albumin nanoparticles for improved storage stability

• Published in: European journal of pharmaceutics and biopharmaceutics Vol. 88; no. 2; pp. 510 - 517
• Main Authors: Dadparvar, Miriam, Wagner, Sylvia, Wien, Sascha, Worek, Franz, von Briesen, Hagen, Kreuter, Jörg
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.10.2014
• Subjects: Blood-Brain Barrier; Blood–brain barrier (BBB); Drug delivery; Drug Stability; Feasibility Studies; Freeze Drying; HI-6; Humans; In Vitro Techniques; Microscopy, Electron, Scanning; Nanoparticles; Organophosphate intoxication; Oximes; Recombinant human serum albumin; Recombinant Proteins - chemistry; Serum Albumin - chemistry; Storage stability; Nanoparticles; Oximes; Storage stability; Organophosphate intoxication; Blood–brain barrier (BBB); Drug delivery; HI-6; Freeze-drying; Recombinant human serum albumin
• ISSN: 0939-6411; 1873-3441; 1873-3441
• DOI: 10.1016/j.ejpb.2014.06.008

•HI-6 can be stabilised by binding to nanoparticles and lyophilisation.•Trehalose- and sucrose-containing formulations were superior to mannitol.•Nanoparticles enabled HI-6 transport over a porcine endothelial cell model. Severe intoxications with organophosphates require the immediate administration of atropine in combination with acetyl cholinesterase (AChE) reactivators such as HI-6. Although this therapy regimen enables the treatment of peripheral symptoms, the blood–brain barrier (BBB) restricts the access of the hydrophilic antidotes to the central nervous system which could lead to a fatal respiratory arrest. Therefore, HI-6-loaded albumin nanoparticles were previously developed to enhance the transport across this barrier and were able to reactivate organophosphate-(OP)-inhibited AChE in an in vitro BBB model. Since HI-6 is known to be moisture-sensitive, the feasibility of freeze-drying of the HI-6-loaded nanoparticles was investigated in the present study using different cryo- and lyoprotectants at different concentrations. Trehalose and sucrose (3%, w/v)-containing formulations were superior to mannitol concerning the physicochemical parameters of the nanoparticles whereas trehalose-containing samples were subject of a prolonged storage stability study at temperatures between −20°C and +40°C for predetermined time intervals. Shelf-life computations of the freeze-dried HI-6 nanoparticle formulations revealed a shelf-life time of 18months when stored at −20°C. The formulations’ efficacy was proven in vitro by reactivation of OP-inhibited AChE after transport over a porcine brain capillary endothelial cell layer model.