Pavol Ďurč

Fast blood plasma separation device for point-of-care applications

In this work, a simple device for extremely fast separation of blood plasma from diluted whole blood was developed. The device accommodates an asymmetric polysulfone membrane/supporting membrane sandwich that allows collection of 10 µL blood plasma into a narrow glass capillary in less than 10 s. The composition of diluent solution was optimized in order to achieve maximum recoveries for selected metabolites of alcohol intoxication. 5% solution of [tris(hydroxymethyl)methylamino] propanesulfonic acid provided recoveries of formate, oxalate and glycolate close to 100% and only moderate erythrocyte lysis. Both charged and uncharged compounds from the whole blood samples can be analyzed in the separated blood plasma by capillary electrophoresis with contactless conductometric detection and spectrophotometry, respectively. The developed device might find wide application in on-site testing and point-of-care analysis, when only microliter volumes of whole blood are available.

Study of Various Parameters that Influence the Content of Exhaled breath Condensate Used in the Diagnosis of Gastroesophageal Reflux Disease

Abstract In this work, various parameters that influence the ionic content and pH of exhaled breath condensate in of the noninvasive diagnosis of gastroesophageal reflux disease were studied. Exhaled breath condensate samples were collected using a miniature and inexpensive sampling device. Capillary electrophoresis with contactless conductometric detection was used to monitor the ionic content of exhaled breath condensate. Background electrolyte composed of 20 mM of 2-(N-Morpholino)ethanesulfonic acid, 20 mM of L-Histidine, 2 mM of 18-Crown-6 and 30 M of cetyltrimethylammonium bromide facilitated the rapid separation of anions and cations, both in less than 2 minutes. The possibility of contamination of the exhaled breath condensate by saliva is discussed in detail. The day-to-day repeatability (n=5) of the ionic content and pH of the exhaled breath condensate was studied and was satisfactory, reflecting mainly the physiological variability

Capillary Electrophoretic Analysis of Exhaled Breath Condensate in the Diagnosis of Gastroesophageal Reflux Disease

Abstract In this work, capillary electrophoresis with contactless conductometric detection (CCD) was used for the analysis of the ionic content of exhaled breath condensate (EBC) to differentiate between healthy individuals and patients with gastroesophageal reflux disease (GERD). The exhaled breath condensate was collected using a miniature sample collection device and the content analyzed using a separation electrolyte composed of 20 mM 2-(N-morpholino)ethanesulfonic acid, 20 mM L-histidine, 2 mM 18-Crown-6 and 30 M cetyltrimethylammonium bromide. The separation of anions took less than 2.5 minutes, while the cations were separated in less than 1.5 minutes. The most significantly elevated ions in the group of patients suffering from gastroesophageal reflux disease were chloride, nitrate, propionate and butyrate. Although the number of subjects was too small to draw definite conclusions with regard to the discriminatory power of these ions, the pilot data are promising for EBC as a useful non-invasive alternative for other methods used in the diagnosis of gastroesophageal reflux disease