title: Simultaneous quantification of catecholamines in rat brain by high-performance liquid chromatography with on-line gold nanoparticle-catalyzed luminol chemiluminescence detection.
abstract: A new method based on high-performance liquid chromatography (HPLC) coupled with on-line gold nanoparticle-catalyzed luminol chemiluminescence (CL) detection was developed for the simultaneous quantitation of catecholamines in rat brain. In the present CL system, gold nanoparticles were produced by the on-line reaction of H2 O2 , NaHCO3 -Na2 CO3 (buffer solution of luminol) and HAuCl4. Norepinephrine (NE), epinephrine (EP) and dopamine (DA) could strongly enhance the CL signal of the on-line gold nanoparticle-catalyzed luminol system. The UV-visible absorption spectra and transmission electron microscopy studies were carried out, and the CL enhancement mechanism was proposed. Catecholamines promoted the on-line formation of more gold nanoparticles, which better catalyzed the luminol-H2 O2 CL reaction. The good separation of NE, EP and DA was achieved with isocratic elution using a mixture of methanol and 0.2% aqueous phosphoric acid (5:95, v/v) within 8.5 min. Under the optimized conditions, the detection limits, defined as a signal-to-noise ratio of 3, were in the range of 1.32-1.90 ng/mL, corresponding to 26.4-38.0 pg for 20 μL sample injection. The recoveries of catecholamines added to rat brain sample were >94.6%, with the precisions <5.5%. The validated HPLC-CL method was successfully applied to determine NE and DA in rat brain without prior sample purification.
authors.affiliation: School of Pharmacy, Anhui Medical University, Hefei, 230032, People's Republic of China.
authors.forename: Chunlei
authors.initials: C
authors.lastname: Mu
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Dong
authors.initials: D
authors.lastname: Wu
authors.forename: Yunjing
authors.initials: Y
authors.lastname: Zhang
authors.forename: Qunlin
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D002395:Catecholamines / Q000032:analysis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D057230:Limit of Detection; D016014:Linear Models; D008163:Luminescent Measurements / Q000379:methods*; D008165:Luminol / Q000032:analysis / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results
chemical_list: D002395:Catecholamines; D008165:Luminol; D006046:Gold
keywords: chemiluminescence; dopamine; epinephrine; norepinephrine; on-line gold nanoparticle