Application Of Spectroscopic Probes In The Study Of Protein - Dodecyl Benzene Sulfonate Role

Many biochemists and chemists are always inceasingly interested in the assembly of small molecules on biomacromolecule . Thus, a stain is often used as a spectral probe in study of interaction of small molecule with macromolecule, macromolecule with macromolecule. An accurate analysis of this interaction is very helpful for us to understand the chemical action occurring in biological cell then to design a new drug or to remove a toxicant from body. But also, understanding this non-covalent bond or covalent bond interaction can help us further investigate the interaction among molecules, e.g. thus to develop a new kind of anticarcinogens. Recently, the microsurface adsorption-spectral correction technique (MSASC) has been applied above. In this work, we further study its application to the aggregation of a non-spectral in visiable light scope compound .sodium dodecyl benzene sulfonate (SDBS) on protein. In addition, the break point approach is the first to be described so as to confirm the characterization of the assembly product.1, We have summaried current situation,methods and meaning of protein with small molecules.described the microsurface adsorption-spectral correction (MSASC) technique and the break point approach . These methods are different from the classical methods e.g. molor ratios> Scatcha^ Pesavento models.2, The interactions of sodium dodecyl benzene sulfonate (SDBS) with proteins: bovine serum albumin (BSA), myoglobin (MB) and ovalbumin (OVA) with brilliant cresyl blue (BCB), polychrome blue B (PCB), pyronin B (PRB) as the spectral probes has been investigated in detail. BCB,PCB and PRB will form cations in aqueous solution and then can be adsorbed on an anionic surfactant e.g. SDBS. Similarly, the protonation of aminos in a protein makes itself carry many positive charges in acidic solution and then SDBS is attracted. Thus ,in theSDBS-BCB.SDBS-PCB and SDBS-PRB solutions.the addition of a protein will replace the BCB.PCB and PRB binding SDBS to form the protein-SDBS aggregate.Experiments have proved that the aggregation of BCB /PCB/PRB on SDBS and assembly of SDBS in protein obey the Langmuir isothermal adsorption. The characterization of the aggregates was made by the MSASC and the break point approach . The aggregates: BCB-SDBS, SDBS90.BSA, SDBS41.OVA and SDBS25.MB are formed at pH 2.81 at room temperature. PCB-SDBS, SDBS92. BSA, SDBS54.OVA and SDBS15. MB are formed at pH 3.88. PRB'SDBS, SDBS110.BSA, SDBSgg.OVA and SDBS23. MB are formed at pH 2.81 The formation constants of the aggregates were determined too. The aggregation of SDBS on protein has been applied to the quantitative detection of protein in samples with satisfactory results.3, The effect of ionic strength and temperature on the aggregation were tested. The results have showed that the interactions between spectrometric probe with SDBS and between SDBS with proteins are veriable with ionic strength and tempbreture.This indicates the interactions are all non-covalent.Otherwise, The electrostatic attraction shortens the distance between molecules and then the fanction of Vander Wall and insertion binding appears. The MSASC technique and the break point approach are helpful for us to accurately analyze the physico-chemical process occurring inside biological cell.