title: Microfluidics based manufacture of liposomes simultaneously entrapping hydrophilic and lipophilic drugs.
abstract: Despite the substantial body of research investigating the use of liposomes, niosomes and other bilayer vesicles for drug delivery, the translation of these systems into licensed products remains limited. Indeed, recent shortages in the supply of liposomal products demonstrate the need for new scalable production methods for liposomes. Therefore, the aim of our research has been to consider the application of microfluidics in the manufacture of liposomes containing either or both a water soluble and a lipid soluble drug to promote co-delivery of drugs. For the first time, we demonstrate the entrapment of a hydrophilic and a lipophilic drug (metformin and glipizide respectively) both individually, and in combination, using a scalable microfluidics manufacturing system. In terms of the operating parameters, the choice of solvents, lipid concentration and aqueous:solvent ratio all impact on liposome size with vesicle diameter ranging from ∼90 to 300nm. In terms of drug loading, microfluidics production promoted high loading within ∼100nm vesicles for both the water soluble drug (20-25% of initial amount added) and the bilayer embedded drug (40-42% of initial amount added) with co-loading of the drugs making no impact on entrapment efficacy. However, co-loading of glipizide and metformin within the same liposome formulation did impact on the drug release profiles; in both instances the presence of both drugs in the one formulation promoted faster (up to 2 fold) release compared to liposomes containing a single drug alone. Overall, these results demonstrate the application of microfluidics to prepare liposomal systems incorporating either or both an aqueous soluble drug and a bilayer loaded drug.
authors.affiliation: Aston Pharmacy School, Life and Health Sciences, Aston University, Birmingham B4 7ET, UK.
authors.forename: Sameer
authors.initials: S
authors.lastname: Joshi
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK.
authors.forename: Maryam T
authors.initials: MT
authors.lastname: Hussain
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK.
authors.forename: Carla B
authors.initials: CB
authors.lastname: Roces
authors.affiliation: Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via F. Marzolo 5, 35131 Padova, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Anderluzzi
authors.affiliation: Aston Pharmacy School, Life and Health Sciences, Aston University, Birmingham B4 7ET, UK.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Kastner
authors.affiliation: Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via F. Marzolo 5, 35131 Padova, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Salmaso
authors.affiliation: Aston Pharmacy School, Life and Health Sciences, Aston University, Birmingham B4 7ET, UK.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Kirby
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK. Electronic address: yvonne.perrie@strath.ac.uk.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Perrie
mesh_terms: D002626:Chemistry, Pharmaceutical / Q000379:methods; D016503:Drug Delivery Systems / Q000379:methods; D057927:Hydrophobic and Hydrophilic Interactions; D008081:Liposomes / Q000737:chemistry*; D044085:Microfluidics / Q000379:methods; D010316:Particle Size; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D012995:Solubility; D012997:Solvents / Q000737:chemistry
chemical_list: D008081:Liposomes; D004364:Pharmaceutical Preparations; D012997:Solvents
keywords: Bilayer loading; Liposomes; Manufacturing; Microfluidics; Poorly soluble drugs; Water soluble drugs