Mechanosynthesis and thermal bio–sensing of beryllium–based molecularly imprinted polymers

Abstract

The adsorption of amino acids on electrode surfaces is pertinent to understanding the interfacial behaviours of biological molecules and addressing industrial challenges associated with their purification and monitoring in downstream processes. Molecularly imprinted polymers (MIPs) are ideal candidates for targeted molecular recognition. Metals offer significant potential for enhancing biological molecule recognition by enabling the creation of selective binding sites within polymeric matrices through molecular imprinting. The metal mediated coordination between the monomer and the biomolecule used as template greatly enhances both the affinity and selectivity of molecular recognition. Herein, beryllium–based natural monomers (curcumin and lawsone) were synthesized and applied as functional monomers in the synthesis of MIPs using the amino acid L–leucine (LEU) as template. Mechanochemistry (ball milling) was chosen as key methodology for the synthesis of both the beryllium–based monomers and MIP (BeMIPMs) fabrication. Subsequently, supercritical CO₂ (scCO₂) technology was used for efficiently desorb of the template, yielding vacant receptors. These two green technologies allowed the preparation of BeMIPMs as ready–to–use and stable dry polymeric powders. The prepared BeMIPM particles were then incorporated into a thermally conductive layer via micro–contact deposition. Their response towards LEU and analogues molecules was analysed using the heat–transfer method (HTM), and their performance was compared to the non–imprinted polymer (BeNIPMs) reference. The generated biosensor was found to have an optimal linear range of 0.30–0.93 mM and LoD of 0.16 mM (obtained by the 3σ method), while also being selective when comparing the thermal response to other analogues molecules (IF_effect-LEU = 1.6–1.8 vs. IF_{analogues-molecule} = 0.5–1.5). BeMIPM shows a promising performance for the monitoring of LEU in purification processes due to its thermal response, inclusive in real samples, offering a low–cost thermal platform for monitoring specific amino acids in complex industrial matrices.