Banca de DEFESA: UILLIAN MOZART FERREIRA DA MATA CERQUEIRA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : UILLIAN MOZART FERREIRA DA MATA CERQUEIRA
DATE: 22/02/2024
TIME: 08:30
LOCAL: www.conferenciaweb.rnp.br
TITLE:

Doehlert design in the development of alternative analytical methods for determining metals in spirulina (Arthrospira sp.) commercial samples.

 

KEY WORDS:

Spirulina, Doehlert design, multivariate optimization, slurry sampling, TMAH alkaline extraction, digital image colorimetry.

 

PAGES: 165
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Analítica
SUMMARY:

Procedures for optimizing analytical methods using multivariate techniques have been increasingly applied as they are more economical and effective. The Doehlert design matrix has gained prominence for being versatile and efficient, in addition to offering greater flexibility in choosing the levels of the variables under study. Additionally, there is a growing demand for sample preparation procedures that are environmentally friendly, enable the availability of analytes with simpler, faster, safer strategies and that provide results as reliable as those obtained by the established methods. In this work, Doehlert matrix was applied in the development of three analytical sample preparation methods aiming to determining metals in spirulina (Arthrospira sp.) – cyanobacterium used as a food supplement in humans and animals and considered by many nutrition science researchers as a functional food. Two alternative methods to sample mineralization were developed: (i) cyanophyte slurry sampling for the determination of Fe, Mn and Zn by FAAS; (ii) alkaline extraction with tetramethylammonium hydroxide (TMAH) in order to determining Ca, Fe, Mg, Mn and Zn by FAAS. A third method was developed applying cloud point extraction for the separation and pre-concentration of copper and determination by Digital Image Colorimetry. The developed methods were validated by obtaining its characteristics of analytical merit and were applied to spirulina samples – powder and capsules – commercialized in the cities of Salvador and Jequié-Ba.

COMMITTEE MEMBERS:
Externo à Instituição - CLEBER GALVAO NOVAES - UESB
Externa à Instituição - LIZ OLIVEIRA DOS SANTOS
Presidente - ***.324.555-** - MARCOS DE ALMEIDA BEZERRA - null
Interno - 268481 - SERGIO LUIS COSTA FERREIRA
Interno - ***.936.635-** - VALFREDO AZEVEDO LEMOS - UFBA
Interno - ***.201.155-** - WALTER NEI LOPES DOS SANTOS - UFBA