Publications by Pharmasan Labs, Inc.

Novel ELISAs for screening of the biogenic amines GABA, glycine, ß-phenylethylamine, agmatine, and taurine using one derivatization procedure of whole urine samples. Huisman, H., Wynveen, P., Nichkova, M., & Kellermann, G. (2010). Journal of Analytical Chemistry, 82(15), 6526–6533. PMID: 20586417

Abstract: The inhibitory neurotransmitters GABA, glycine and agmatine and neuromodulators beta-phenylethylamine (beta-PEA) and taurine are important biogenic amines of the sympathetic and parasympathetic nervous systems in the body. Abnormalities in the metabolism of these biomarkers have been implicated in a vast number of neurological diseases. Novel competitive immunoassays, using one unique whole urine derivatization procedure applicable for all five biomarkers, have been developed. The determination of these biomarkers was highly reproducible: the coefficient of variance of inter- and intra-assay variation is between 3.9% and 9.8% for all assays. The assays show a good linearity in urine samples within the range of 100-400 mg Cr/dL and specificity when urine samples are spiked with biogenic amines. The recoveries are between 76 and 154%. The correlation between HPLC and ELISA for glycine and taurine (n = 10) showed regression coeffcients of 0.97 and 0.98, respectively. An in vivo study on the urinary clearance of beta-PEA, agmatine and taurine after oral intake by healthy individuals demonstrated the specificity and clinical significance of these new immunoassays. The immunoassays are useful for clinical and basic research where a fast and accurate assay for the screening of biogenic amines in urine is required, without preclearance of the sample. Download Publication



Studies on the immune response and preparation of antibodies against a large panel of conjugated neurotransmitters and biogenic amines: specific polyclonal antibody response and tolerance. Huisman, H., Wynveen, P., & Setter, P.W. (2010). Journal of Neurochemistry, 112, 840–852. PMID: 19912471

Abstract: We described the production and characterization of antibodies against three important groups of neuro-active haptens, e.g., neurotransmitters and biogenic amines. First, from the tryptophan metabolic pathway: tryptamine, serotonin, 5-hydroxy-indole acetic acid, and melatonin. Secondly, the tyrosine metabolic pathway: tyramine, dopamine, dihydroxyphenyl acetic acid, and norepinephrine. Thirdly, antibodies against excitatory and inhibitory neurotransmitters: glycine, glutamate, glutamine, and GABA. Immunogenic conjugates were prepared after linking haptens to carrier proteins. Most antibodies displayed high specificity against corresponding neuro-active haptens conjugated in vitro and in situ in biological specimens, but not to closely related conjugated metabolites, precursors, pharmaceuticals, agonists, antagonists, or free neuro-active haptens. Conjugated norepinephrine was highly tolerant in different animal species and produced incidentally a short specific antibody response. Download Publication