Banca de DEFESA: Vinicius Cambraia Pereira

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : Vinicius Cambraia Pereira
DATE: 20/09/2023
TIME: 09:00
LOCAL: IQ
TITLE:

FLEXIBLE INTERDIGITATED SILVER/NANOMATERIAL SENSORS AIMING AT THE DETECTION OF TRICYCLIC ANTIDEPRESSANTS WITH ECOLOGICAL RISK POTENTIAL

KEY WORDS:

Impedance spectroscopy; Layer-by-layer; Electronic tongue; Emerging contaminants; Water quality

PAGES: 69
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SUMMARY:

The contamination of surface waters with pharmaceutical residues, particularly the tricyclic antidepressants nortriptyline (NTP), amitriptyline (AMTP), and carbamazepine (CBZ), has been increasingly common. It is also known that these substances are capable of mimicking the functioning of endocrine substances in an uncontrolled manner, posing serious risks to the aquatic environment and humans. Given this context, the objective of this study was to develop electrochemical sensors using interdigitated silver electrodes modified with nanomaterial films to create a multisensory system known as an electronic tongue (ET) for detecting these antidepressants in different matrices, such as ultrapure water, tap water, and water from Lake Paranoá in Brasília-DF. The detection was carried out using an ET system composed of an array of six chemical sensors modified with nanomaterials, impedance analyzer, multiplexing unit, and a principal component analysis (PCA) algorithm for data pattern analysis and interpretation. Initially, the individual responses of the sensors to each analyte were evaluated using impedance spectroscopy, and the spectra were fitted with equivalent circuit models. Among the tested circuits, the one that best fit the experimental data was a series combination of RC and a parallel combination of RC. Furthermore, it was observed that the discrimination of samples occurred satisfactorily in the frequency range of 1 kHz to 10 kHz. Thus, samples of the three antidepressants at different concentrations were analyzed at a frequency of 1 kHz. It was observed that the electrical responses (capacitance and resistance) of the sensor array formed unique electrical fingerprints for each investigated analyte, which could be satisfactorily discriminated with the help of PCA plots. In fact, a correlation was noted between the variance contained in the principal components and the concentration of each analyte, allowing for their quantification in a range from 5 to 100 mmol L-1. This behavior was particularly satisfactory for AMTP. Finally, it was found that the developed ET is capable of discriminating the three analytes regardless of the study matrix, indicating a potential for practical application.

COMMITTEE MEMBERS:
Presidente - 1892565 - LEONARDO GIORDANO PATERNO
Interno - 1260083 - PAULO EDUARDO DE BRITO
Interna - 1601059 - RENATA AQUINO DA SILVA
Externo à Instituição - MARCO ANTONIO DE SOUZA