Study on the interaction of oxymatrine with bovine serum albumin

Abstract

The binding reaction of oxymatrine (OMT) with bovine serum albumin (BSA) was studied by the methods of isothermal titration calorimetry, fluorescence, and circular dichroism (CD) spectroscopy. The thermodynamic results indicated that there were two classes of binding sites on the BSA molecule for OMT molecule. When the drug molecule binding to the first class of sites, the standard changes of enthalpy (DH 1°) and entropy (DS 1°) were (-1.07 ± 0.50) kJ/mol and (98.3 ± 0.50) J/ mol/K, respectively. The possible largest number of binding site (N 1 ) was (10.0 ± 0.20). This type of binding was an enthalpy-entropy synergically driven process. On the second class of binding sites, the standard changes of enthalpy (DH 2°) and entropy (DS 2°) were (1.91 ± 0.03) kJ/ mol and (79.8 ± 0.40) J/mol/K, respectively. The possible largest number of binding site (N 2 ) was (25.0 ± 0.30). This type of binding was entropy driven process. The intrinsic fluorescence of BSA was slightly quenched by the formation of BSA-OMT complex. The CD spectra experiment showed that the a-helix contents of BSA decreased. These revealed that the microenvironment and conformation of BSA were changed in the binding reaction.

Leveraging Electrostatic Interactions for Drug Delivery to the Joint

“…86 As a result, albumin commonly interacts with positively charged carriers. 87,88 This could result in a decreased surface charge on these carriers and hence lower the ability for these to target anionic cartilage tissues if delivered systemically. On the other hand, albumin association with carriers has been shown to reduce clearance mechanisms, evade immune mechanisms, and improve system bioavailability.…”

Survey of the year 2009: applications of isothermal titration calorimetry

“…In 2009 we identified more than 400 articles after searching Web of Science, PubMed, SciDir and OVID databases using ‘isothermal AND titration AND calorimetry’ or ITC or ‘Isothermal Titration Calorimetry’ search terms. These have been classified into the following categories: Pre‐2009 references cited in the text and review articles 1–43 Protein‐protein and protein‐peptide interactions 44–124 Protein/peptide‐small molecule interactions 125–218 Protein/peptide‐metal ion interactions 219–253 Protein/peptide‐nucleic acid interactions 254–273 Protein/peptide‐lipid interactions 274–292 Protein/peptide‐polysaccharide interactions 293–316 Nucleic acid‐small molecule interactions 317–348 Small molecule interactions …”