TY - JOUR
T1 - Optimization of protein solution by a novel experimental design method using thermodynamic properties
AU - Kim, Nam Ah
AU - An, In Bok
AU - Lee, Sang Yeol
AU - Park, Eun Seok
AU - Jeong, Seong Hoon
PY - 2012/9
Y1 - 2012/9
N2 - In this study, the structural stability of hen egg white lysozyme in solution at various pH levels and in different types of buffers, including acetate, phosphate, histidine, and Tris, was investigated by means of differential scanning calorimetry (DSC). Reasonable pH values were selected from the buffer ranges and were analyzed statistically through design of experiment (DoE). Four factors were used to characterize the thermograms: calorimetric enthalpy (ΔH), temperature at maximum heat flux (Tm), van't Hoff enthalpy (ΔHV), and apparent activation energy of protein solution (Eapp). It was possible to calculate Eapp through mathematical elaboration from the Lumry-Eyring model by changing the scan rate. The transition temperature of protein solution, Tm, increased when the scan rate was faster. When comparing the Tm, ΔH V, ΔH, and Eapp of lysozyme in various pH ranges and buffers with different priorities, lysozyme in acetate buffer at pH 4.767 (scenario 9) to pH 4.969 (scenario 11) exhibited the highest thermodynamic stability. Through this experiment, we found a significant difference in the thermal stability of lysozyme in various pH ranges and buffers and also a new approach to investigate the physical stability of protein by DoE.
AB - In this study, the structural stability of hen egg white lysozyme in solution at various pH levels and in different types of buffers, including acetate, phosphate, histidine, and Tris, was investigated by means of differential scanning calorimetry (DSC). Reasonable pH values were selected from the buffer ranges and were analyzed statistically through design of experiment (DoE). Four factors were used to characterize the thermograms: calorimetric enthalpy (ΔH), temperature at maximum heat flux (Tm), van't Hoff enthalpy (ΔHV), and apparent activation energy of protein solution (Eapp). It was possible to calculate Eapp through mathematical elaboration from the Lumry-Eyring model by changing the scan rate. The transition temperature of protein solution, Tm, increased when the scan rate was faster. When comparing the Tm, ΔH V, ΔH, and Eapp of lysozyme in various pH ranges and buffers with different priorities, lysozyme in acetate buffer at pH 4.767 (scenario 9) to pH 4.969 (scenario 11) exhibited the highest thermodynamic stability. Through this experiment, we found a significant difference in the thermal stability of lysozyme in various pH ranges and buffers and also a new approach to investigate the physical stability of protein by DoE.
KW - Aggregation
KW - Design of experiment (DoE)
KW - Differential scanning calorimetry
KW - Lysozyme
KW - Protein stability
KW - Thermodynamic stability
UR - http://www.scopus.com/inward/record.url?scp=84872108448&partnerID=8YFLogxK
U2 - 10.1007/s12272-012-0912-2
DO - 10.1007/s12272-012-0912-2
M3 - Article
C2 - 23054718
AN - SCOPUS:84872108448
SN - 0253-6269
VL - 35
SP - 1609
EP - 1619
JO - Archives of Pharmacal Research
JF - Archives of Pharmacal Research
IS - 9
ER -