Polyelectrolyte brushes on porous carbon electrodes for protein capture and electrochemical release
Typ
Examensarbete för masterexamen
Master's Thesis
Master's Thesis
Program
Materials chemistry (MPMCN), MSc
Publicerad
2024
Författare
Bång, Elin
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Biopharmaceuticals are medical drugs produced from biological components. Necessary
steps in the manufacturing includes isolation and purification of biomolecules,
for which chromatography is a common technique. However, it requires harmful
elution chemicals, that can affect the desired product. To achieve a more efficient
and non-invasive way for biopharmaceutical production, there is an interest of developing
new methods for purification of biomolecules.
The electrode surface of Nyctea Technologies utilizes polyelectrolyte brushes responsive
to pH-stimuli. By alternating pH, or by electric signals, the brushes can switch
between charged and neutral state. This enables interactions that allows the brushes
to reversible capture and release biomolecules like proteins. The polymer coating
has previous been applied to gold coated steel surfaces. The aim of this project was
to investigate alternative substrate materials with the purpose to improve the protein
binding capacity of the electrodes. Displaying attractive properties such as high
chemical stability and electrical conductivity, having high specific surface area, and
high availability at low cost, porous carbon electrode materials was further explored.
The synthesis of poly(methacrylic acid) (PMAA) brushes was performed on reticulated
vitreous carbon (RVC) and on carbon felt. By thermogravimetric analysis
(TGA) the polymer amount on the coated materials could be quantified. It was
confirmed to be PMAA on the felt, while the RVC showed no clear signs of attached
polymer. The protein binding capacity of the carbon electrodes was evaluated by
pH controlled catch and release of protein, using bovine serum albumin (BSA). The
RVC was unsuccessful while the felt preformed better, and was chosen to be further
developed as an electrode material. The carbon felt electrodes was assembled
in capsules and connected to a chromatography system. Results made clear that
protein was captured by the electrodes, and protein release was possible both by pH
elution and by electrochemistry, making the carbon felt a promising candidate for
future research.
Beskrivning
Ämne/nyckelord
Polyelectrolyte brushes , Porous carbon , Protein immobilization , Electrochemistry