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Lipase-based in vitro release assays for pharmaceutical lipid formulations

Saffer, Leonard LU (2015) KLG920 20151
Food Technology and Nutrition (M.Sc.)
Abstract
The purpose of this project was to develop and test lipase-based in vitro release (IVR) assays for model and active pharmaceutical ingredients (API) entrapped in lipid formulations based on mixtures of phosphatidylcholine (PC) and glycerol dioleate (GDO).
Two dyes, Fluorescein disodium salt and Patent Blue V sodium salt, functioning as model drug compounds, were investigated separately in the PC/GDO formulation. As the lipid formulation containing one of the two dyes was injected in vitro into a buffered saline solution, the lipids self-assembled into liquid crystal (LC) phases which trap the dye inside a nearly spherical LC depot. The dye was then released slowly over time. In the presence of lipases, the dye release was accelerated by... (More)
The purpose of this project was to develop and test lipase-based in vitro release (IVR) assays for model and active pharmaceutical ingredients (API) entrapped in lipid formulations based on mixtures of phosphatidylcholine (PC) and glycerol dioleate (GDO).
Two dyes, Fluorescein disodium salt and Patent Blue V sodium salt, functioning as model drug compounds, were investigated separately in the PC/GDO formulation. As the lipid formulation containing one of the two dyes was injected in vitro into a buffered saline solution, the lipids self-assembled into liquid crystal (LC) phases which trap the dye inside a nearly spherical LC depot. The dye was then released slowly over time. In the presence of lipases, the dye release was accelerated by biodegradation of the lipids. The IVR rate was followed by spectrophotometric measurements of the dye concentration in the aqueous release medium.
This thesis describes the investigation of many parameters such as the suitability of the two dyes as model APIs, the effect of two different triacyl glycerol lipases (TGL) and a phospholipase, different concentrations of lipases as well as mixtures of different lipases, different lipid formulation types, the difference between a single vial experimental setup and a 96 well plate setup, as well as an overall evaluation of the project.
It was shown that the addition of lipases dramatically increases the IVR rate, even at low concentrations. The effect on IVR was much higher for the phospholipase than for the TGLs.
This research is of interest to the research- and development based pharmaceutical company Camurus AB in Lund, Sweden, currently developing pharmaceutical products based on the lipid liquid crystal formulation technology. The results will be used in the assessment and development of in vitro in vivo correlation (IVIVC) assays which are useful for formulation development and for regulatory purposes in conjunction with post registration changes related to Chemistry, Manufacturing and Controls (CMC). (Less)
Popular Abstract (Swedish)
När man tar en medicin är det viktigt att man tar rätt dos. Tar man för liten dos uteblir den önskade terapeutiska effekten och tar man för stor dos kan bieffekterna bli allvarliga. Skillnaden mellan terapeutisk och giftig dos kallas terapeutiskt fönster. Om det terapeutiska fönstret är snävt kan man behöva ta små doser ofta för att en säker och effektiv koncentration av läkemedlet i kroppen under hela behandlingen. Det skulle kunna innebära att en patient måste ta flera tabletter under dagen och under natten. Att missa en dos skulle kunna vara allvarligt.
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author
Saffer, Leonard LU
supervisor
organization
course
KLG920 20151
year
type
H2 - Master's Degree (Two Years)
subject
keywords
phospholipase, triacyl glycerol lipase, in vitro release, fluorescein., patent blue, pharmaceutical technology, läkemedelsteknologi, Lipid formulation, phosphatdyl choline, glycerol dioleate
language
English
id
7410085
date added to LUP
2015-07-02 14:08:08
date last changed
2015-07-02 14:08:08
@misc{7410085,
  abstract     = {The purpose of this project was to develop and test lipase-based in vitro release (IVR) assays for model and active pharmaceutical ingredients (API) entrapped in lipid formulations based on mixtures of phosphatidylcholine (PC) and glycerol dioleate (GDO).
Two dyes, Fluorescein disodium salt and Patent Blue V sodium salt, functioning as model drug compounds, were investigated separately in the PC/GDO formulation. As the lipid formulation containing one of the two dyes was injected in vitro into a buffered saline solution, the lipids self-assembled into liquid crystal (LC) phases which trap the dye inside a nearly spherical LC depot. The dye was then released slowly over time. In the presence of lipases, the dye release was accelerated by biodegradation of the lipids. The IVR rate was followed by spectrophotometric measurements of the dye concentration in the aqueous release medium.
This thesis describes the investigation of many parameters such as the suitability of the two dyes as model APIs, the effect of two different triacyl glycerol lipases (TGL) and a phospholipase, different concentrations of lipases as well as mixtures of different lipases, different lipid formulation types, the difference between a single vial experimental setup and a 96 well plate setup, as well as an overall evaluation of the project.
It was shown that the addition of lipases dramatically increases the IVR rate, even at low concentrations. The effect on IVR was much higher for the phospholipase than for the TGLs.
This research is of interest to the research- and development based pharmaceutical company Camurus AB in Lund, Sweden, currently developing pharmaceutical products based on the lipid liquid crystal formulation technology. The results will be used in the assessment and development of in vitro in vivo correlation (IVIVC) assays which are useful for formulation development and for regulatory purposes in conjunction with post registration changes related to Chemistry, Manufacturing and Controls (CMC).},
  author       = {Saffer, Leonard},
  keyword      = {phospholipase,triacyl glycerol lipase,in vitro release,fluorescein.,patent blue,pharmaceutical technology,läkemedelsteknologi,Lipid formulation,phosphatdyl choline,glycerol dioleate},
  language     = {eng},
  note         = {Student Paper},
  title        = {Lipase-based in vitro release assays for pharmaceutical lipid formulations},
  year         = {2015},
}