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Fluorimetric Method for the Determination of Histidine in Random Human Urine Based on Zone Fluidics.

ABSTRACT: In the present study, the determination of histidine (HIS) by an on-line flow method based on the concept of zone fluidics is reported. HIS reacts fast with o-phthalaldehyde at a mildly basic medium (pH 7.5) and in the absence of additional nucleophilic compounds to yield a highly fluorescent derivative (?_ex/?_em = 360/440 nm). The flow procedure was optimized and validated, paying special attention to its selectivity and sensitivity. The LOD was 31 nmol·L^-1, while the within-day and day-to-day precisions were better than 1.0% and 5.0%, respectively (n = 6). Random urine samples from adult volunteers (n = 7) were successfully analyzed without matrix effect (<1%). Endogenous HIS content ranged between 116 and 1527 ?mol·L^-1 with percentage recoveries in the range of 87.6%-95.4%.

SUBMITTER: Alevridis A

PROVIDER: S-EPMC7180633 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Fluorimetric Method for the Determination of Histidine in Random Human Urine Based on Zone Fluidics.

Alevridis Antonios A Tsiasioti Apostolia A Zacharis Constantinos K CK Tzanavaras Paraskevas D PD

Molecules (Basel, Switzerland) 20200404 7

In the present study, the determination of histidine (HIS) by an on-line flow method based on the concept of zone fluidics is reported. HIS reacts fast with o-phthalaldehyde at a mildly basic medium (pH 7.5) and in the absence of additional nucleophilic compounds to yield a highly fluorescent derivative (λex/λem = 360/440 nm). The flow procedure was optimized and validated, paying special attention to its selectivity and sensitivity. The LOD was 31 nmol ...[more]

PMID: 32260350

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