Phase diagrams, osmotic second virial coefficient, and protein crystallization with volatile salt

• Grant number: 10/52524-5
• Support Opportunities: Regular Research Grants
• Start date: April 01, 2011
• End date: March 31, 2013
• Field of knowledge: Engineering - Chemical Engineering - Industrial Operations and Equipment for Chemical Engineering
• Principal Investigator: Everson Alves Miranda
• Grantee: Everson Alves Miranda
• Host Institution: Faculdade de Engenharia Química (FEQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Crystallization and precipitation, are important unit operations in protein downstream processes. The efficiency of crystallization/precipitation depends on the location of the phases in equilibrium diagrams, which are commonly referred to as maps that represent the material state as a function of relevant variables in the system. The aim of this study is to determine experimentally protein precipitation/crystallization phase diagrams using the volatile salt ammonium carbamate as precipitating agent. The completion of this investigation will relate the phase location in the diagrams with the parameter "B22" since the protein-protein interactions are relevant and the thermodynamic parameter known as the osmotic second virial coefficient, "B22", is correlated to the phase behavior of a protein solution. It is intended to identify in the diagrams along with the analysis of "B22" conditions where the formation of amorphous or crystalline precipitate occurs. This study will allow selection of optimal conditions in order to reduce the amount of protein used and the number of conditions initially tested for successful crystallization. The proteins used in this work as model proteins will be bovine and porcine insulin and lysozyme. The salt ammonium carbamate was chosen as the salting-out agent since it is an alternative to the use of conventional salts for this type of precipitation. Normally, during the stages of separation, large volumes of solutions containing electrolytes are generated. Volatile electrolytes can have easier removal from solution to the vapor phase with temperature increase or pressure decrease. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MEDEIROS HIRATA, GISELE ATSUKO; PESSOA FILHO, PEDRO DE ALCANTARA; MIRANDA, EVERSON ALVES. Solid-liquid equilibrium for proteins in solutions with an unconventional salt (ammonium carbamate): Phase behavior analysis. Fluid Phase Equilibria, v. 443, p. 1-8, JUL 15 2017. (10/52524-5)