title: Quantitative evaluation of proteins with bicinchoninic acid (BCA): resonance Raman and surface-enhanced resonance Raman scattering-based methods.
abstract: A rapid and highly sensitive bicinchoninic acid (BCA) reagent-based protein quantitation tool was developed using competitive resonance Raman (RR) and surface-enhanced resonance Raman scattering (SERRS) methods. A chelation reaction between BCA and Cu(+), which is reduced by protein in an alkaline environment, is exploited to create a BCA-Cu(+) complex that has strong RR and SERRS activities. Using these methods, protein concentrations in solutions can be quantitatively measured at concentrations as low as 50 μg mL(-1) and 10 pg mL(-1). There are many advantages of using RR and SERRS-based assays. These assays exhibit a much wider linear concentration range and provide an additional one (RR method) to four (SERRS method) orders of magnitude increase in detection limits relative to UV-based methods. Protein-to-protein variation is determined using a reference to a standard curve at concentrations of BSA that exhibits excellent recoveries. These novel methods are extremely accurate in detecting total protein concentrations in solution. This improvement in protein detection sensitivity could yield advances in the biological sciences and medical diagnostic field and extend the applications of reagent-based protein assay techniques.
authors.affiliation: Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chunchon 200-701, Korea.
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yu
authors.forename: Youngju
authors.initials: Y
authors.lastname: Lee
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.forename: Bing
authors.initials: B
authors.lastname: Zhao
authors.forename: Young Mee
authors.initials: YM
authors.lastname: Jung
mesh_terms: D000818:Animals; D003300:Copper / Q000737:chemistry; D006801:Humans; D010084:Oxidation-Reduction; D011506:Proteins / Q000032:analysis* / Q000737:chemistry; D011804:Quinolines / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013499:Surface Properties
chemical_list: D011506:Proteins; D011804:Quinolines; D003300:Copper; C047117:bicinchoninic acid