Banca de QUALIFICAÇÃO: AMANDA LUISE ALVES NASCIMENTO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : AMANDA LUISE ALVES NASCIMENTO
DATE: 31/10/2023
TIME: 09:00
LOCAL: Google meet
TITLE:

Development of colorimetric paper analytical device (PAD) for forensic markers determination and identification in biological samples

KEY WORDS:

sexual crimes; forensic application; fructose; colorimetric detection.

PAGES: 70
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUMMARY:

Identification of body fluids is a crucial step in criminal investigation1 especially when dealing with sexual crimes, due to the high recurrence of violence of this nature in which 1 in 5 women have suffered abuse2. The collection of biological samples, such as semen, at the crime scene or on the victim is important to confirm the possible rape, also making it possible to identify the perpetrator. Different methodologies for identifying markers3 present in semen in high concentrations, such as fructose, have been evaluated, however, there is still a demand for quick and low-cost tests to aid in criminal expertise. Thus, the present work aimed at the use of a paper-based analytical device (PAD) based on the colorimetric variation of the reactive systems due to the fructose present in the semen sample, generating a blue colored chromophore (Fig.1a). The colorimetric change in the test zones was visually observed and the images captured by the scanner allow a quantitative analytical response to be obtained. Different parameters were optimized in the development of the device, seeking to improve the identification and sensitivity of the method, such as: order of addition and concentration of reagents, buffer system and drying time, allowing to obtain a linear response for fructose in the range (25 - 200 mg L- 1), with a detection limit of 10 mg L-1. The concentration range normally reported in semen samples ranges from 1400 to 6300 mg L-1,4,5 indicating that the method perfectly meets the purpose, and, it is noteworthy that for blood, urine and saliva samples, fructose levels are tens to hundreds of times smaller. The selectivity study was carried out with interferents such as glucose and inositol (Fig. 1b), showing no significant difference (α = 0.05). The device applied to a real sample proved to be sensitive and reliable whose qualitative and quantitative analysis directly at the crime scene appears as a scientific and technological innovation that will contribute to the elucidation of these crimes

COMMITTEE MEMBERS:
Externo(a) à Instituição - CLÉSIA CRISTINA NASCENTES
Externo(a) à Instituição - BRUNO GABRIEL LUCCA - UFMS
Interno(a) - 1997465 - DANIELA SANTOS ANUNCIACAO
Interno(a) - 2089941 - DIMAS JOSE DA PAZ LIMA
Interno(a) - 1904678 - JANAINA HEBERLE BORTOLUZZI
Presidente - 1613338 - JOSUE CARINHANHA CALDAS SANTOS
Externo(a) à Instituição - RODOLFO DE MELO MAGALHÃES SANTANA - UFBA