Sains Malaysiana 42(4)(2013): 529–535

 

Molecularly Imprinted Polymer Synthesis Using RAFT Polymerisation

(Sintesis Polimer Molekul Tercetak Menggunakan Pempolimeran RAFT)

 

Peter A.G. Cormack* & Faizatul Shimal Mehamod

WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde

Thomas Graham Building, 295 Cathedral Street, Glasgow, G1 1XL, Scotland

 

Faizatul Shimal Mehamod

Department of Chemical Sciences, Faculty of Science and Technology

Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia

 

Received: 26 June 2011 / Accepted: 9 May 2012

 

ABSTRACT

In this paper, the synthesis and characterisation of caffeine-imprinted polymers are described. The polymers were prepared in monolithic form via both reversible addition-fragmentation chain-transfer (RAFT) polymerisation and conventional free radical polymerisation, using methacrylic acid and ethylene glycol dimethacrylate as the functional monomer and crosslinking agent, respectively. The potential benefits in applying RAFT polymerisation techniques towards the synthesis of molecularly imprinted polymers (MIPs) are explored and elucidated. The pore structures of the polymers produced were characterised by nitrogen sorption porosimetry and the molecular recognition properties of representative products were evaluated in high-performance liquid chromatography (HPLC) mode. Molecular imprinting effects were confirmed by analysing the relative retentions of analytes on imprinted and non-imprinted HPLC stationary phases. It was found that a caffeine-imprinted polymer synthesised by RAFT polymerisation was superior to a polymer prepared using a conventional synthetic approach; the imprinting factor and column efficiency were found to be higher for the former material.

 

Keywords: Caffeine; molecular recognition; molecularly imprinted polymers; novel stationary phases; RAFT polymerisation

 

ABSTRAK

Dalam penyelidikan ini, sintesis dan pencirian terhadap polimer tercetak-kafein telah diterangkan. Polimer tersebut telah disediakan dalam bentuk monolitik melalui pempolimeran tambahan-fragmentasi rantai pindah boleh balik (RAFT) dan pempolimeran konvensional radikal bebas, menggunakan asid metaakrilik sebagai monomer berfungsi dan etilena glikol sebagai ejen taut silang. Potensi yang dapat dimanfaatkan dengan menggunakan teknik pempolimeran RAFT dalam sintesis polimer molekul tercetak (MIPs) telah diterokai dan difahami. Struktur liang polimer yang terhasil telah dicirikan dengan menggunakan porosimeter penyerapan nitrogen manakala pengecaman sifat molekul produk tersebut telah dinilai dalam mod kromatografi cecair berprestasi tinggi (HPLC). Hasil pencetakan molekul dikenal pasti dengan menganalisis perbezaan relatif antara puncak analit-tercetak dan analit-tidak tercetak dalam fasa gerak HPLC. Didapati polimer tercetak-kafein melalui pempolimeran RAFT adalah lebih baik daripada polimer yang disintesis melalui kaedah konvensional; kesan pencetakan dan kecekapan kolum didapati lebih tinggi bagi bahan yang pertama tadi.

 

Kata kunci: Fasa gerak terbaharu; kafein; pempolimeran RAFT; pengecaman molekul; polimer molekul tercetak

 

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*Corresponding author; email: Peter.Cormack@strath.ac.uk