| Abstract | Elektroforeza na mikročipu uspješno je upotrebljena u ovom radu za separaciju i
kvantifikaciju β-alanina i L-histidina, pojedinačno i u smjesi. Za ispitivanja je korišten
ureĎaj za elektroforezu na mikročipu sa kapacitivno spregnutim, beskontaktnim,
konduktometrijskim detektorom, C4D, koji radi na frekvenciji od 4 MHz. Separacija je
provedena na polimetil-metakrilatnom (PMMA) mikročipu, duljine separacijskog kanala
75 mm. Kao pufer korištena je 0,5 M octena kiseline, pH = 2,5. Primijenjeni napon
injektiranja bio je 0,80 kV, a napon separacije 3,80 kV. Ustanovljen je linearni odziv C4D
detektora za β-alanin u području od 2,5 x 10-5 M do 7,5 x 10-5 M (R2 = 0,9990) i za L
histidin u području 1,5 x 10-5 M do 5 x 10-5 M (R2 = 0,9538) sa granicom detekcije ispod 1
mg/L. C4D detektor pokazao je i linearni odziv za smjesu β-alanina i L-histidina u
području od 2,5 x 10-5 M do 7,5 x 10-5 M u odnosu na alanin i histidin (R2 = 0,9926 i
0,9640, respektivno). Točnost odreĎivanja pojedinačnih aminokiselina, kao i njihov sadrţaj
u smjesi, testirani su metodom poznatog dodatka. |
| Abstract (english) | Microchip electrophoresis (MCE) was successfully used in these investigations for
separation and quantification of β-alanine and L-histidine, both single and in a mixture. A
microchip electrophoresis device equipped with capacitively-coupled contactless
conductivity detector (C4D) operating at 4 MHz was used for the investigations. The
separation was carried out on a polymethyl-metacrylate (PMMA) chip with the separation
channel length of 75 mm. Acetic acid solution of the concentration 0,5 M was used as a
buffer (pH = 2,5). The applied injection voltage was 0,80 kV and the separation voltage
was 3,80 kV. A linear relationship between C4D detector response and β-alanine
concentration was assessed in the range 2,5 x 10-5 M - 7,5 x 10-5 M (R2 = 0,9990), and in
the range of 1,5 x 10-5 M - 5 x 10-5 M (R2 = 0,9538) for L-histidine, with a detection limit
below 1 mg/L. C4D detector exhibited a linear relationship toward the mixture of β-alanine
and L-histidine in the range of 2,5 x 10-5 M - 7,5 x 10-5 M related to β-alanine and L
histidine particularly (R2 = 0,9926 and 0,9640, respectively). The accuracy of
determination for single aminoacids, and their content in a mixture, were tested by known
addition method. |
