Resumen de Development and application of metal-organic frameworks and other materials in microextraction/chromatographic and sensing
The aim of the present Doctoral Thesis revolves around: i) the synthesis of new materials so as to isolate analytes of interest from real complex samples; ii) the combination of polymer-based capillary columns with functional materials in order to enhance the separation performances; and iii) the design of paper-based devices for sensing purposes.
The distribution of the present manuscript can be divided in four big sections:
The first one (chapters I-III) is a general introduction, which includes some general aspects of the main researching lines of the present Doctoral Thesis.
The second big group (Chapter IV-XVI) is devoted to the explanation and discussion of the developed methods using different materials as extractive phases (i.e. MOFs and/or molecularly imprinted polymers (MIPs)). The sorbents have been applied to several real samples, including environmental, food and biological samples, in order to retain a wide range of analytes, including endocrine-disrupting chemicals (EDCs), pesticides, polycyclic aromatic hydrocarbons (PAHs), vitamins, synthetic cannabinoids (SCs), antibiotics, benzomercaptans and phospholipids (PLs). In some cases, the hybridization of individual components was assessed, showing synergistic effects and improved features. All the materials were characterized in depth and the methods were rigorously validated and compared, in most cases, with the benchmark materials or homologues. Furthermore, the specific interaction between analyte-sorbent was considered by synthesizing BioMOFs, which possess amino acids in their network. This fact not only did improve the specificity (host-chemistry), but also the sustainability of the sorbents, being all of them biocompatible and biodegradable.
On the other hand, special chapters are dedicated to MIP as SPE sorbent for organophosphorus pesticides removal and the application of MOF-based monolith for nano LC separation. Furthermore, two reviews were also included in the field of affinity-MOF-based materials and novel platforms in combination with MOFs/COFs.
The third group (Chapter XVII-XXII) is devoted to the development of µPADs for point-of-care (POC) analysis. For this purpose, portable and lightweight vertical-flow card devices were designed with accessible stationery materials and a desktop scanner was used for the image acquisition. Finally, the data were treated with free software ImageJ. In this context, three contributions have been developed including Fe(II)/Fe(III) speciation and TPC quantification in wines samples and another one regarding TPC quantification in fruit samples including MOFs in the µPAD card. All these contributions are the result of a 3-months research stay in Porto, Portugal.
Last but not least, sensing application were developed by using bioluminescent enzymes (luciferase). In this case, a first contribution was done by studying the mutagenesis of complementary DNA (cDNA) encoding for target enzyme. Then, ZIF-8 was attached to this luciferase and the resulting biocomposite was applied as bioluminescent probe. Both the synthesis and the analytical performance were evaluated. Finally, a µPAD sensor was developed with this hybrid material for ATP determination as a rapid POC analysis of urinary tract infection. Surprisingly, the sensor was able to retain the initial performance after 3 weeks of storage at room temperature. All these contributions are the result of a 6-months research stay in Bologna, Italy.
In the last part of this Thesis, a general conclusion, including the main results and discussion, can be found.
