In‐capillary derivatization with fluorescamine for the rapid determination of adamantane drugs by capillary electrophoresis with UV detection

Abstract

In-capillary derivatization using fluorescamine as the labeling reagent was proposed to enhance the detectability of adamantine drugs (memantine, amantadine and rimantadine) by spectrophotometric detection. Fluorescamine and the drugs were delivered to the capillary electrophoresis instrument at a ratio of 10:1 by zone injection. The derivatization reaction occurred following the application of voltage (20 kV). The derivatized products, hydrolyzed- fluorescamine and excess fluorescamine were separated in 7 min using 100 mM borate buffer (pH 10.0) containing 0.1% w/v of Brij®-35 and 20% v/v of acetonitrile. Validation data showed good linearity (r > 0.98), precision (%RSDs < 3.4), and accuracy (recoveries ranging from 98.0 to 102.0%). The detection and quantitation limits are in the range of 6.0-8.5 and 18-25 μM, respectively. The validation data is comparable to reported methods, however, the current method offers better precision with enhanced sensitivity (up to six times). Applications of the method show percent labeled amounts found in the studied samples within 100.6-109.3%, which complied with the United States Pharmacopeia limit (90.0-110.0%). The method was simple, rapid and, automated, which required no extra instrumentation or skillful operators.

Sensitivity enhancement in capillary electrophoresis and their applications for analyses of pharmaceutical and related biochemical substances

“…Good linearity (r 2 > 0.98), precision (%RSDs < 3.4), and accuracy (recoveries ranging from 98.0 to 102.0%) were found, while LOD and LOQ were in the range of 6.0-8.5 and 18-25 μM, respectively. The percent of labeled amounts in the studied samples were 100.6-109.3%, which complied with the United States Pharmacopeia limit (90.0-110.0%) [92]. In addition, in-capillary derivatization coupled with fluorescence detection for forensic analysis of morphine and morphine-6-glucuronide in human urine was investigated by Zarad et al [93].…”

“…For anionic analysis, the capillary surface is usually coated with long-chain alkyl ammonium salts (e.g., CTAB, tetradecyl trimethyl ammonium bromide) or polycations (e.g., hexadimetrine) to reverse the EOF and to generate the co-EOF migration [87]. Derivatizations for CE are divided into three subclasses based on where the derivatization takes place [88,89]; (1) precapillary or offline [90], (2) postcapillary [91], and (3) on-or in-line capillary derivatization [92]. Precapillary derivatization requires large amounts of chelating agents.…”

Characterization of Fipronil in Micellar Medium with Brij 35

“…Currently, there is a wide variety of applications for Brij 35, including its use as a support for chemical and enzymatic reactions [15], as well as a vehicle in pharmaceutical preparations and agricultural formulations [16]. Regarding its analytical applications, Brij 35 has been used to form micellar media in the separation of drugs by capillary electrophoresis [17], as well as the mobile phase in liquid chromatography [18]. Also, some authors used it in sample treatment with techniques such as liquid-liquid microextraction [19].…”

Development and validation of HPLC method for simultaneous determination of rimantadine marketed product

“…Quantitative methods for the determination of rimantadine have been developed using various analytical techniques [8][9][10]. Validated a method for the quantitative trace analysis of rimantadine in poultry muscle using column-switch liquid chromatography coupled to tandem mass spectrometry, demonstrating its suitability for the analysis of antiviral drugs [11].…”