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This work presents a novel approach for tailoring molecularly imprinted polymers (MIPs) with a preliminary stage of atom transfer radical polymerization (ATRP), for a more precise definition of the imprinted cavity. A well-defined copolymer of acrylamide and N,N′-methylenebisacrylamide (PAAm-co-PMBAm) was synthesized by ATRP and applied to gold electrodes with the template, followed by a crosslinking reaction. The template was removed from the polymer matrix by enzymatic/chemical action. The surface modifications were monitored via electrochemical impedance spectroscopy (EIS), having the MIP polymer as a non-conducting film designed with affinity sites for CA15-3. The resulting biosensor exhibited a linear response to CA15-3 log concentrations from 0.001 to 100 U/mL in PBS or in diluted fetal bovine serum (1000×) in PBS. Compared to the polyacrylamide (PAAm) MIP from conventional free-radical polymerization, the ATRP-based MIP extended the biosensor's dynamic linear range 10-fold, improving low concentration detection, and enhanced the signal reproducibility across units. The biosensor demonstrated good sensitivity and selectivity. Overall, the work described confirmed that the process of radical polymerization to build an MIP material influences the detection capacity for the target substance and the reproducibility among different biosensor units. Extending this approach to other cancer biomarkers, the methodology presented could open doors to a new generation of MIP-based biosensors for point-of-care disease diagnosis. [ABSTRACT FROM AUTHOR]

Currently, the development of durable eco-efficient materials is a priority for the construction sector. In this regard, the alkaline activation of fly ash is a promising solution: it allows ordinary Portland cement (OPC), responsible for 5% of carbon dioxide emissions worldwide, to be replaced by an industrial by-product. Moreover, the resulting alkali-activated concrete (AAC) also presents an advantage, compared to OPC-based concrete, in terms of enhanced durability. The project herein described combines the huge advantage of AAC for the sustainability of the construction sector with the intrinsic characteristics of AAC that make it most suitable for the precast industry. The prefabrication of AAC façade panels was defined as the main goal, which makes this project one of the very few studies that refer to the production and the structural behaviour of AAC elements of considerable size. The following objectives were defined: (a) to study the properties of the AAC; (b) to develop the industrial production process of the AAC panels, including heat curing; and (c) to study the structural behaviour of the panels. [ABSTRACT FROM AUTHOR]