Orientador: Sonia Maria Alves Bueno / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-02T17:38:51Z (GMT). No. of bitstreams: 1 Serpa_Gisele_M.pdf: 3619704 bytes, checksum: 1feef42faa8bb785a83f4c9f481a438c (MD5) Previous issue date: 2002 / Resumo: Anticorpos monoc1onais são imunoglobulinas secretadas por uma célula híbrida, chamada hibridoma, que é fonnada pela fusão de um linfócito (produtor de anticorpos) e uma célula de mieloma, o que faz do hibridoma uma célula produtora de anticorpos virtualmente imortal. Os anticorpos monoc1onais têm sido utilizados nas áreas analítica e terapêutica, o que implica na necessidade de obtenção de anticorpos de alta pureza. Muitos estudos têm sido realizados visando a purificação de anticorpos monoc1onais, e destacam-se as técnicas de adsorção seletiva, como as cromatografias de troca iônica, hidrofóbicas e de a:f11Údade. Neste trabalho aplicou-se a cromatografia em membranas de álcool polietileno-vinílico, derivatizadas com ácido iminodiacético (IDA), com íons metálicos imobilizados na purificação de anticorpos monoc1onais IgGl a partir de sobrenadante de cultura celular. Para determinar as melhores condiçôes de adsorção e eluição, foram testados os íons Cu2+, Ni2+, Zn2+ e C02+, na presença de diferentes sistemas tamponantes. A seletividade dos metais, em cada um dos sistemas, foi determinada através de eletroforese SDS-PAGE e testes ELISA das frações dos picos de proteína obtidos. A melhor condição de purificação foi a alimentação de sobrenadante de cultura celular previamente precipitado e dialisado com solução de sulfato de amônio, em coluna contendo PEVA-IDA-Zn2+, em presença de tampão Tris-HCI 50 mM a pH 7,0 e eluição por aumento de concentração de Tris. A partir das isotermas de adsorção, determinou-se a capacidade máxima de adsorção e a constante de dissociação do complexo IDA­Zn2+-IgGl que de acordo com o ajuste dos parâmetros pelo modelo de Langmuir, mostraram uma alta capacidade de adsorção (63,4 mg/g de membrana seca) e uma constante de dissociação (8,lxlO-6 M) característica de sistemas de média afinidade. Foram também determinadas as curvas de ruptura para o processo proposto, através de experimentos de fIltração a diferentes vazões de alimentação, utilizando um módulo contendo as fibras ocas com Zn2+ imobilizado, construído em nosso laboratório / Abstract: Monoc1onal antibodies are immunoglobulins produced by a hybrid cell ca11ed hybridoma. These cells result from the fusion of lymphocytes with malignant myeloma cells. Hybridomas cells express both the lymphocyte's property of specific-antibody production and the immortal character of the myeloma cells. Monoc1onal antibodies have been used in analy1ica1 and therapeutica1 areas. This application needs high1y pure antibodies. Many techniques have been studied focusing monoc1onal antibodies purification. These techniques inc1ude ion exchange, hydrophobic and affinity chromatography. In this study, we applied polyethylenevinyl alcohol (PEV A) membranes in the purification of monoc1onal antibody from cell culture supem.atant. These membranes were derivatized with the quelant agent, iminodiacetic acid (IDA). We evaluated the adsorption and purification of monoc1onal antibodies on the matrix with different immobilized metal ios, Cu2+, Ni2+, Zn2+ and C02+ and with different buffers. According to SDS­PAGE electrophoresis and ELISA analysis, the higher selectivity was obtained in the presence of 50 mM Tris-HCl buffer, pH 7,0 and with elution by increasing Tris concentration, with immobilized Zn2+, wich provided the purification of IgG with traces of albumin. The adsorbent capacity and the dissociation constant of the complex IDA-Zn2+-IgGI were determinated from adsorption isotherms. According to the Langmuir model, the results indicated that the matrix presents high adsorption capacity (63,4 mg/g de chy membrane) and a dissociation constant (8,1 x 10-6 M) characteristic for intermediate affinity systems. We also evaluated the breaktrough curves for PEVA-IDA-Zn2+ membrane chromatography for the antibodies purification using different flow rates. These breaktrough CUIVes are important to sca1e up procedure / Mestrado / Desenvolvimento de Processos Biotecnologicos / Mestre em Engenharia Química

Electrospinning and electrospraying are electrohydrodynamic processes used for the fabrication of nano- and microfiber membranes and the deposition of particles on the membrane. Despite the numerous research papers found in the literature on electrospun polymers and their application in water treatment, not much is reported on the functionalization of electrospun nano- or microfibers and the deposition of ceramic nanoparticles on their surface by electrospraying. The use of these two processes may increase the efficiency of membranes in removing contaminants. In the present research, the processes of electrospinning and electrospraying are described and the factors affecting electrospinning are investigated. All parameters affecting the production of smooth NFs and NPs are discussed. A literature review of the recent advances in electrospinning and electrospray applications, as well as the application of NFs membranes in water treatment, has been described. This research has been designed based on the knowledge gaps identified in the literature. Detailed experiments were carried out on the preparation of PAN_P and Cs_P NFs membranes by electrospinning technique, the NFs membranes were then functionalized with different functional groups. The membranes were used for removal (Chapter 3) and degradation (Chapters 4 and 5) of dyes synthetic solutions. In the case of degradation, the membranes were electrosprayed with TiO2 NPs. All membranes were characterized by standard spectroscopic, microscopic, surface analytical, and thermal methods. Adsorption of MB, RB, and ST from a synthetic aqueous solution on the membranes PAN and EA-g-PAN NFs decreased in the order PAN<EA-g-PAN. The adsorption isotherm for the dyes fitted well with the models of Langmuir and Freundlich. The values of the correlation coefficient (r2) for Langmuir varied from 0.940 to 0.995 and for Freundlich from 0.941 to 0.998. The slightly increased values of the correlation coefficient in the case of Freundlich indicate that condensation (physical adsorption) of dyes on the NFs membranes also occurred in addition to the formation of monolayers. PAN_P NFs membranes prepared by electrospinning were functionalized with DETA to produce a functionalized PAN _F NFs membrane. TiO2 NPs synthesized in the laboratory were anchored to the surface of the PAN_F NFs membrane by electrospray to prepare PAN _Coa. A second PAN_Co was prepared by embedding TiO2 NPs into the PAN_P NFs by electrospinning. A similar strategy was also used for the Cs and TiO2 NPs system. The PAN_Coa NFs membrane was used for the degradation of MO while the Cs_Coa NFs membrane was used for the degradation of MB. The higher photocatalytic activity of PAN _Coa NFs membranes (92%, 20 ppm, and 99.5%, 10 ppm) compared to PAN_Co NFs membranes (41.64%) was due to the smaller band gap, high surface roughness, and large surface area. Also, the higher photocatalytic activity of the Cs_Coa NFs membrane (89%) compared to TiO2/Cs composite (Cs_Co) NFs membranes (40%) was due to a balance between the band gap, high surface roughness, and lower surface area. BET showed that the isotherms and hysteresis were similar for all NFs membranes, and they were classified as isotherm type IV and hysteresis H3 (IUPAC), corresponding to mesopores and slit-shaped pores.