Determination of Protein by Fluorescence Enhancement of Curcumin in Lanthanum-Curcumin-Sodium Dodecyl Benzene Sulfonate-Protein System

Journal Article · Sat Jan 01 04:00:00 EST 2011 · Journal of Fluorescence

DOI:https://doi.org/10.1007/s10895-010-0686-1· OSTI ID:1015087

Wang, Feng ^[1]; Huang, Wei ^[1]; Zhang, Yunfeng ^[1]; Wang, Mingyin ^[1]; Sun, Lina ^[1]; Tang, Bo ^[2]; Wang, Wei ^[3]

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1. Zaozhuang University, People's Republic of China
2. Shandong University, Jinan, China
3. ORNL

We found that the fluorescence intensity of the lanthanum (La(3+))-curcumin (CU) complex can be highly enhanced by proteins in the presence of sodium dodecyl benzene sulphonate (SDBS). Based on this finding, a new fluorimetric method for the determination of protein was developed. Under optimized conditions, the enhanced intensities of fluorescence are quantitatively in proportion to the concentrations of proteins in the range 0.0080-20.0 g mL(-1) for bovine serum albumin (BSA) and 0.00080-20.0 g mL(-1) for human serum albumin (HSA) with excitation of 425 nm, and 0.00020-20.0 g mL(-1) for bovine serum albumin (BSA) and 0.00080-20.0 g mL(-1)for human serum albumin (HSA) with excitation of 280 nm, while corresponding qualitative detection limits (S/N 3) are as low as 5.368, 0.573, 0.049, 0.562 g mL(-1), respectively. Study on reaction mechanism reveals that proteins can bind with La(3+), CU and SDBS through self-assembling function with electrostatic attraction, hydrogen bonding, hydrophobic interaction and van der Waals forces, etc. The proteins form a supermolecular association with multilayer structure, in which La(3+)-CU is clamped between BSA and SDBS. The unique high fluorescence enhancement of CU is resulted through synergic effects of favorable hydrophobic microenvironment provided by BSA and SDBS, and efficient intermolecular energy transfer among BSA, SDBS and CU. In energy transfer process, La(3+) plays a crucial role because it not only shortens the distance between SDBS and CU, but also acts as a "bridge" for transferring the energy from BSA to CU.

• Research Organization: Oak Ridge National Laboratory (ORNL); Oak Ridge National Environmental Research Park
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1015087
• Journal Information: Journal of Fluorescence, Journal Name: Journal of Fluorescence Journal Issue: 1 Vol. 21; ISSN 1053-0509
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
ALBUMINS
BENZENE
BLOOD SERUM
BONDING
CATTLE
CURCUMIN
ELECTROSTATICS
ENERGY TRANSFER
EXCITATION
FLUORESCENCE
HYDROGEN
LANTHANUM
PROTEINS
REACTION KINETICS
SENSITIVITY
SODIUM
VAN DER WAALS FORCES