Determination of some antirheumatics by capillary isotachophoresis

Abstract

Isotachophoresis (ITP) was applied for the determination of some antirheumatic drugs (fenoprofen, naproxen, ibuprofen, and ketoprofen) in human serum. The leading electrolyte contained hydrochloric acid (10 mmol x L(-1)), creatinine (pH 4.5) and methylhydroxyethyl cellulose (0.1%). The terminating electrolyte was 2-(N-morpholino)ethanesulfonic acid (10 mmol x L(-1)) adjusted with tris(hydroxymethyl)aminomethane to pH 6.9. The ITP separations were carried out in column-coupling configuration of the separation unit provided with a preseparation column of 160 x 0.8 mm inner diameter (ID) and analytical column of 160 x 0.3 mm ID. The limit of detection for ibuprofen, fenoprofen, and naproxen in serum by direct sampling was 0.008, 0.005 and 0.004 mmol x L(-1). The limit of detection for ketoprofen in serum after ethanol precipitation was 0.001 mmol x L(-1).

A high throughput and sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for the estimation of bisoprolol in human plasma using multiplexing technique

“…Only few analytical methods have been reported in literature for monitoring plasma, serum and urine levels of bisoprolol [4][5][6][7]. The techniques used in the reported methods include use of a HPLC method with fluorescence detection [4][5][6], and a capillary isotachophoresis method [7].…”

“…The techniques used in the reported methods include use of a HPLC method with fluorescence detection [4][5][6], and a capillary isotachophoresis method [7]. The HPLC methods has limit of quantification ≥5 ng/mL for estimation of bisoprolol in plasma and ≥10 ng/mL for urine [4][5][6].…”

“…The HPLC methods has limit of quantification ≥5 ng/mL for estimation of bisoprolol in plasma and ≥10 ng/mL for urine [4][5][6]. The capillary isotachophoresis method has a limit of quantification of 40 g/mL and 3 g/mL for estimation of bisoprolol in serum and urine, respectively [7]. The reported methods are not sensitive enough to detect sub-nanogram levels of bisoprolol in human plasma [4][5][6][7].…”

“…The capillary isotachophoresis method has a limit of quantification of 40 g/mL and 3 g/mL for estimation of bisoprolol in serum and urine, respectively [7]. The reported methods are not sensitive enough to detect sub-nanogram levels of bisoprolol in human plasma [4][5][6][7]. The reported HPLC methods follow time consuming and error prone liquid-liquid extraction procedure involving drying and reconstitution [4][5][6].…”

“…Also these methods have long run time, low recovery and large plasma processing volume [4][5][6]. The capillary isotachophoresis method additionally involves solid-phase extraction which makes the method lengthy [7]. As the use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for analysis of drug candidates in biological matrices has grown exponentially in the last decade, due to its un-matched sensitivity, extraordinary selectivity and rapid rate of analysis, it was necessary to develop a sensitive, selective and rapid LC-MS/MS analytical method for the quantification of bisoprolol in human plasma.…”