| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 766.69 KB | Adobe PDF |
Advisor(s)
Abstract(s)
This work uses surface imprinting to design a novel smart plastic antibodymaterial (SPAM) for Haemoglobin
(Hb). Charged binding sites are described here for the first time to tailor plastic antibody nanostructures for a
large size protein such as Hb. Its application to design small, portable and low cost potentiometric devices is
presented. The SPAM material was obtained by linking Hb to silica nanoparticles and allowing its ionic
interaction with charged vinyl monomers. A neutral polymeric matrix was created around these and the
imprinted protein removed. Additional materials were designed in parallel acting as a control: a neutral
imprinted material (NSPAM), obtained by removing the charged monomers from the procedure, and the
Non-Imprinted (NI) versions of SPAM and NSPAM by removing the template. SEM analysis confirmed the
surface modification of the silica nanoparticles. All materials were mixed with PVC/plasticizer and applied
as selective membranes in potentiometric transduction. Electromotive force (emf) variations were
detected only for selective membranes having a lipophilic anionic additive in the membrane. The
presence of Hb inside these membranes was evident and confirmed by FTIR, optical microscopy and
Raman spectroscopy. The best performance was found for SPAM-based selective membranes with an
anionic lipophilic additive, at pH 5. The limits of detection were 43.8 mg mL 1 and linear responses were
obtained down to 83.8 mg mL 1, with an average cationic slope of +40 mV per decade. Good selectivity
was also observed against other coexisting biomolecules. The analytical application was conducted
successfully, showing accurate and precise results.