Author(s):
Gomes, Catarina ; Sadoyan, Gayane ; Dias, Rolando ; Costa, Mário Rui
Date: 2017
Persistent ID: http://hdl.handle.net/10198/14698
Origin: Biblioteca Digital do IPB
Subject(s): Molecular imprinting; Supercritical CO2 extraction; Plant extracts
Description
Molecularly imprinted polymer (MIP) particles are here developed to target phenolic compounds present in mixtures resulting from supercritical extraction processes. Engineered MIP particles are synthetized considering different polymerization processes to tailor products morphology (e.g. precipitation or inverse-suspension polymerization to obtain micro-particles [1]) and also diverse functional monomers to explore preferential interactions with the template polyphenols (e.g. polydatin, resveratrol, etc). Moreover, MIP particles with surface grafted functional polymer chains (e.g. using RAFT polymerization [2,3]) are produced to assess the improvement of the selectivity of MIPs towards the target polyphenols, namely through the tuning of the hydrophilic/hydrophobic effects (amphiphilic materials are generated). The produced MIP particles are applied for the identification, separation and concentration of phenolic compounds present in vegetable extracts. Different plants abundant in the Trás-os-Montes and Alto Douro region (e.g. vineyard, chestnut tree, olive tree, cherry tree, etc) are considered as potential sources of phenolic compounds. Supercritical extraction with CO2 is used to obtain the vegetable extracts (see Figure 1) and the effects of the operation conditions (temperature, pressure, vegetable used, etc) on extract composition is also assessed. Molecular recognition capabilities of the MIPs synthetized towards the polyphenols are evidenced (e.g. packing the particles for chromatography) but hydrophilic/hydrophobic interactions are unavoidable and a solvent gradient is needed.