Banca de DEFESA: MARCELO DA SILVA PEDRO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MARCELO DA SILVA PEDRO
DATE: 20/02/2020
TIME: 14:00
LOCAL: AUDITÓRIO DO CATRE
TITLE:

Effect of flow patterns on the partitioning of biomolecules (protein and ampicillin) in aqueous two-phase system (ATPS) using microsystems.

KEY WORDS:

BSA, liquid-liquid extraction, flow pattern, microdevice

PAGES: 76
BIG AREA: Engenharias
AREA: Engenharia Química
SUMMARY:

Protein separation is a complex process and involves several processing steps, making the process expensive and slow. In this work, a microsystem was built to separate model proteins using the liquid-liquid extraction technique using a two-phase aqueous system (ATPS) of polymer and salt. ATPS was formed by the mixture of the polyethylene glycol-PEG polymer (25% w / w), potassium phosphate (10% w / w) and distilled water (65% w / w). The microsystem channels have diameters of 0.51 mm, 1.14 mm and 1.8 mm. The total flow range ranges from 20 to 700 μL / min. The effect of the flow pattern on the extraction of biomolecules (protein and ampicillin) was investigated. Flow patterns were determined using SAB composed of PEG / phosphate with different molecular molecular weights (PEG 1500, PEG 4000 and PEG 6000) and silicone mini-channels with circular geometry arranged in sinusoidal shape and diameter 1.8 mm. As expected, the gradual increase in liquid flow made it possible to achieve the following flow patterns in sequence: slug, droplet and parallel flow. The high viscosity of the polymeric phases prevented the parallel flow from occurring in systems with higher molecular weight of PEG. Initially, the effect of flow patterns on the recovery of bovine serum albumin protein (from English bovine serum albumin-BSA) was studied for the three flow patterns obtained in the PEG 1500 / dibasic potassium phosphate system in the residence times of 3, 5 and 10 min in the 1.8 mm mini channel. In this condition, the highest BSA recovery efficiencies were 38%, 56% and 32% for 10 min incubation and using slug, droplet and parallel flow patterns, respectively. Then, the recovery of a smaller molecule (ampicillin), whose molar mass is 349 g / mol, was tested for comparison with the BSA protein which has a molar mass of 66500 g / mol (large molecule), with a greater recovery of the smaller molecule. BSA recovery tests were also performed using a 1.14 mm mini-channel and 0.510 mm microchannel using the droplet flow pattern and residence times of 3, 5 and 10 min. The volumetric mass transfer coefficients () were obtained in the range of 0.41-2.75x10^-3 (s-1) for all microchannels and flow patterns. The flow regimes affected the BSA recovery, with the droplet regime providing the greatest recovery. The same was not observed for the smaller molecule, antibiotic ampicillin, which recovered independently of the flow regime. The reduction in the diameter of the channels and the increase in residence times had a positive effect on the extraction efficiency and the maximum efficiency value obtained was 69% for the 0.510 mm microchannel and 10 min residence time for the BSA protein. The flow and scale reduction regime had a positive effect for , with higher values being obtained for the droplet and 0.510 mm microchannel regime.

BANKING MEMBERS:
Externo ao Programa - 089.656.434-73 - CARLOS EDUARDO DE ARAÚJO PADILHA - UFRN
Presidente - 1584174 - DOMINGOS FABIANO DE SANTANA SOUZA
Interno - 1346198 - EVERALDO SILVINO DOS SANTOS
Externo à Instituição - JUAN ALBERTO CHAVEZ RUIZ - ISI-ER
Externa ao Programa - 1218001 - LIANA FRANCO PADILHA