title: Capillary electrophoretic separation of biologically active amines and acids using nanoparticle-coated capillaries.
abstract: This manuscript describes dynamic coating of capillaries with poly(L-lysine) (PLL) and silica nanoparticles (SiO2 NPs) and use of the as-prepared capillaries for the separation of biogenic amines and acids by CE in conjunction with LIF detection. The directions of EOF are controlled by varying the outmost layer of the capillaries with PLL and SiO2 NPs, respectively. Over the pH range 3.0-5.0, the (PLL-SiO2NP)n-PLL capillaries have an EOF toward the anodic end and are more suitable for the separation of acids with respect to speed, while the (PLL-SiO2NP)n capillaries have an EOF toward the cathodic end and are more suitable for the separation of biogenic amines regarding speed and sensitivity. The separations of standard solutions containing five amines and two acids by CE with LIF detection using (PLL-SiO2NP)2-PLL and (PLL-SiO2NP)3 capillaries were accomplished within 10 and 7 min, providing plate numbers of 3.8 and 5.0x10(4) plates/m for 5-hydroxytryptamine (5-HT), respectively. The LODs for 5-HT and 5-hydroxyindole-3-acetic acid (5-HIAA) are 32 and 2 nM and 0.2 and 1.5 nM when using the (PLL-SiO2NP)2-PLL and (PLL-SiO2NP)3 capillaries, respectively. Identification and quantification of 5-HIAA, homovanillic acid, and DL-vanillomandelic acid in urine samples from a male before and after drinking green tea were tested to validate practicality of the present approach. The results show that the (PLL-SiO2NP)2-PLL capillary provides greater resolving power, while the (PLL-SiO2NP)3 capillary provides better sensitivity, higher efficiency, and longer durability for the separation of the amines and acids.
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei, Taiwan.
authors.forename: Yu-Fen
authors.initials: YF
authors.lastname: Huang
authors.forename: Cheng-Kang
authors.initials: CK
authors.lastname: Chiang
authors.forename: Yang-Wei
authors.initials: YW
authors.lastname: Lin
authors.forename: Kungtien
authors.initials: K
authors.lastname: Liu
authors.forename: Chou-Chen
authors.initials: CC
authors.lastname: Hu
authors.forename: Ming-Jong
authors.initials: MJ
authors.lastname: Bair
authors.forename: Huan-Tsung
authors.initials: HT
authors.lastname: Chang
mesh_terms: D001679:Biogenic Amines / Q000032:analysis* / Q000378:metabolism / Q000652:urine; D019075:Electrophoresis, Capillary / Q000295:instrumentation; D004837:Epinephrine / Q000032:analysis; D005453:Fluorescence; D006719:Homovanillic Acid / Q000032:analysis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006897:Hydroxyindoleacetic Acid / Q000032:analysis; D007834:Lasers; D008297:Male; D053758:Nanoparticles; D011107:Polylysine; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012701:Serotonin / Q000032:analysis; D012822:Silicon Dioxide; D013662:Tea; D014363:Tryptamines / Q000032:analysis; D014364:Tryptophan / Q000032:analysis
chemical_list: D001679:Biogenic Amines; D013662:Tea; D014363:Tryptamines; D011107:Polylysine; D012701:Serotonin; C030820:tryptamine; D006897:Hydroxyindoleacetic Acid; D012822:Silicon Dioxide; D014364:Tryptophan; D006719:Homovanillic Acid; D004837:Epinephrine