Molecularly Imprinted Methyl-Modified Hollow TiO<sub>2</sub> Microspheres
The possibility of generating organically modified hollow TiO<sub>2</sub> microspheres via a simple sol-gel synthesis was demonstrated for the first time in this work. A mixture of titania precursors, including an organically modified precursor, was used to obtain methyl-modified hollow...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-12-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/27/23/8510 |
| _version_ | 1797462576378937344 |
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| author | Vanessa R. A. Ferreira Manuel A. Azenha Carlos M. Pereira António F. Silva |
| author_facet | Vanessa R. A. Ferreira Manuel A. Azenha Carlos M. Pereira António F. Silva |
| author_sort | Vanessa R. A. Ferreira |
| collection | DOAJ |
| description | The possibility of generating organically modified hollow TiO<sub>2</sub> microspheres via a simple sol-gel synthesis was demonstrated for the first time in this work. A mixture of titania precursors, including an organically modified precursor, was used to obtain methyl-modified hollow TiO<sub>2</sub> microspheres selective for bilirubin by the molecular imprinting technique (Methyl-HTM-MIM). Methyl-HTM-MIM were prepared by a sol-gel method using titanium (IV) isopropoxide (TTIP), and methyltitanium triisopropoxide (MTTIP) as precursors. Two ratios of titania precursors were tested (1/6 and 1/30 mol<sub>MTTIP</sub>/mol<sub>TTIP</sub>). With the characterization results obtained by the SEM and ATR-FTIR techniques, it was possible to establish that only the 1/30 mol<sub>MTTIP</sub>/mol<sub>TTIP</sub> ratio allowed for the preparation of hollow spheres with a reasonably homogeneous methylated-TiO<sub>2</sub> shell. It was possible to obtain a certain degree of organization of the hybrid network, which increased with calcination temperatures. By adjusting isothermal adsorption models, imprinting parameters were determined, indicating that the new methylated microspheres presented greater selectivity for bilirubin than the totally inorganic hollow TiO<sub>2</sub> microspheres. The effectiveness of the molecular imprinting technique was proven for the first time in an organically modified titania material, with imprinting factor values greater than 1.4, corresponding to a significant increase in the maximum adsorption capacity of the template represented by the molecularly imprinted microspheres. In summary, the results obtained with the new methyl-HTM-MIM open the possibility of exploring the application of these microspheres for selective sorption (separation or sensing, for example) or perhaps even for selective photocatalysis, particularly for the degradation of organic compounds. |
| first_indexed | 2024-03-09T17:38:34Z |
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| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-09T17:38:34Z |
| publishDate | 2022-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-45b55d0197c6402ca653d263b54185e12023-11-24T11:43:23ZengMDPI AGMolecules1420-30492022-12-012723851010.3390/molecules27238510Molecularly Imprinted Methyl-Modified Hollow TiO<sub>2</sub> MicrospheresVanessa R. A. Ferreira0Manuel A. Azenha1Carlos M. Pereira2António F. Silva3CIQ-UP, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, PortugalCIQ-UP, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, PortugalCIQ-UP, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, PortugalCIQ-UP, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, PortugalThe possibility of generating organically modified hollow TiO<sub>2</sub> microspheres via a simple sol-gel synthesis was demonstrated for the first time in this work. A mixture of titania precursors, including an organically modified precursor, was used to obtain methyl-modified hollow TiO<sub>2</sub> microspheres selective for bilirubin by the molecular imprinting technique (Methyl-HTM-MIM). Methyl-HTM-MIM were prepared by a sol-gel method using titanium (IV) isopropoxide (TTIP), and methyltitanium triisopropoxide (MTTIP) as precursors. Two ratios of titania precursors were tested (1/6 and 1/30 mol<sub>MTTIP</sub>/mol<sub>TTIP</sub>). With the characterization results obtained by the SEM and ATR-FTIR techniques, it was possible to establish that only the 1/30 mol<sub>MTTIP</sub>/mol<sub>TTIP</sub> ratio allowed for the preparation of hollow spheres with a reasonably homogeneous methylated-TiO<sub>2</sub> shell. It was possible to obtain a certain degree of organization of the hybrid network, which increased with calcination temperatures. By adjusting isothermal adsorption models, imprinting parameters were determined, indicating that the new methylated microspheres presented greater selectivity for bilirubin than the totally inorganic hollow TiO<sub>2</sub> microspheres. The effectiveness of the molecular imprinting technique was proven for the first time in an organically modified titania material, with imprinting factor values greater than 1.4, corresponding to a significant increase in the maximum adsorption capacity of the template represented by the molecularly imprinted microspheres. In summary, the results obtained with the new methyl-HTM-MIM open the possibility of exploring the application of these microspheres for selective sorption (separation or sensing, for example) or perhaps even for selective photocatalysis, particularly for the degradation of organic compounds.https://www.mdpi.com/1420-3049/27/23/8510methyl-modifiedhollow TiO<sub>2</sub> microspheresselectivitymolecular imprintingsol-gel |
| spellingShingle | Vanessa R. A. Ferreira Manuel A. Azenha Carlos M. Pereira António F. Silva Molecularly Imprinted Methyl-Modified Hollow TiO<sub>2</sub> Microspheres Molecules methyl-modified hollow TiO<sub>2</sub> microspheres selectivity molecular imprinting sol-gel |
| title | Molecularly Imprinted Methyl-Modified Hollow TiO<sub>2</sub> Microspheres |
| title_full | Molecularly Imprinted Methyl-Modified Hollow TiO<sub>2</sub> Microspheres |
| title_fullStr | Molecularly Imprinted Methyl-Modified Hollow TiO<sub>2</sub> Microspheres |
| title_full_unstemmed | Molecularly Imprinted Methyl-Modified Hollow TiO<sub>2</sub> Microspheres |
| title_short | Molecularly Imprinted Methyl-Modified Hollow TiO<sub>2</sub> Microspheres |
| title_sort | molecularly imprinted methyl modified hollow tio sub 2 sub microspheres |
| topic | methyl-modified hollow TiO<sub>2</sub> microspheres selectivity molecular imprinting sol-gel |
| url | https://www.mdpi.com/1420-3049/27/23/8510 |
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