İdrar Örneklerinde L-2-Hidroksiglutarik Asitin Kapiler Elektroforez-İndirekt UV Dedeksiyon ile Hızlı Tayini

Öz

Amaç: L-2 hidroksiglutarik asidüri (L2HGA) otozomal resesif geçişli, psikomotor gerilik, serebellar ataksi ve değişken makrosefali veya epilepsi ile karakterize edilen nadir görülen nörömetabolik bir hastalıktır. Hastalık biyokimyasal olarak idrarda, beyin omurilik sıvısında ve çok az miktarda plazmada artmış L-2HGA seviyeleri ile tanımlanır. Bu çalışmada, idrarda L-2-hidroksiglutarik asitin tayini için hızlı ve hassas bir kapiler elektroforez yöntemi geliştirilmiştir. Materyal ve Metot: L-2-hidroksiglutarik asit kromofor gruba sahip olmadığı için, indirekt UV deteksiyon metodu uygulanmıştır. Çalışma tamponu pH 5.6’da 0.1 mmol/L setiltrimetilamonyum bromür (CTAB) içeren 10 mmol/L 2,6-piridindikarboksilik asitten (PDC) oluşmaktadır. PDC iyi bir kromoforik özellik göstermesinden dolayı indirekt deteksiyon için uygundur. CTAB elektro-osmotik akışı (EOF) ters çevirmek için kullanılmıştır. Bulgular: L-2-hidroksiglutarik asit için tayin limiti 1.16 μmol/L’dir. Geliş zamanı ise 2.0 dakikadan daha az bir süredir. Geliştirilen metod 16 L-2-hidroksiglutarik asidüri hastasından ve 4 sağlıklı gönüllüden toplanan idrar örneklerine uygulanmıştır. Sonuç: Hasta bireylerin idrarındaki L-2-hidroksiglutarik asitin konsantrasyonu 48.9 – 1,15 µg/mL arasında bulunmuştur.

Anahtar Kelimeler

• Kapiler elektroforez
• İndirekt UV deteksiyon
• L-2-hidroksiglutarik asit

RAPID DETERMINATION OF L-2-HYDROXYGLUTARIC ACID IN URINE SAMPLES BY CAPILLARY ELECTROPHORESIS WITH INDIRECT UV DETECTION

Öz

Aim: L-2-hydroxyglutaric aciduria (L2HGA) which is autosomal recessive and characterized by psychomotor retardation, cerebellar ataxia, variable macrocephaly, and epilepsy is a rarely seen neurometabolic disease. The disease is biochemically identified by slightly increased L-2HGA levels in urine, cerebrospinal fluid, and plasma. A sensitive and rapid capillary electrophoretic technique was used for the determination of L2HGA in urine. Materials and Method: Since the L2HGA lacks of chromophore, an indirect UV detection method was applied. The running electrolyte consisted of 10 mmol/L 2,6-pyridinedicarboxylic acid (PDC) at pH 5.6 containing 0.1 mmol/L of cetyltrimethylammonium bromide (CTAB). PDC was chosen because of its good chromophoric property for indirect UV detection. CTAB was used as electro-osmotic flow (EOF) reversal. Results: The method was well-validated in the selected conditions. The detection limit of the method L2HGA was 1.16 μmol/L. The migration time of L2HGA was less than 2.0 min. The developed method was applied to the urine samples collected from 16 patients who suffer from L-2-hydroxyglutaric aciduria and 4 healthy volunteers. Conclusion: L-2-hydoxyglutaric acid concentration was found between 48.9 – 1,15 µg/mL in patients.

Anahtar Kelimeler

• Capillary electrophoresis
• indirect UV detection
• L-2-hydroxyglutaric acid

Kaynakça

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