29 research outputs found
Spectrophotometric method for the simultaneous determination of piroxicam and 2-aminopyridine
737-740A
rapid and simple spectrophotometric method is proposed for the simultaneous determination
of piroxicam (Pi) and 2-aminopyridine (2-Ap). Piroxicam is stable under basic hydrolysis,
but yields 2-Ap as one of the degradation products under acid hydrolysis. The
method is based on the measurement of absorbances of 2-Ap and Pi at 300 and 360
nm, respectively, and the calculations are based on the binary method. The
absorbances of both compounds obey Beer-Lambert 's law over the concentration range
of 5-25 µg L-1
with good linearity (r2>0.99).
The recoveries are with in 100.8- 106.4% for Pi and are within 96.4-98.9% for
2- Ap. Precision is good with acceptable limits of detection (LOD) and
quantitation (LOQ) for both compounds. The method has been applied for the
determination of Pi and 2-Ap in piroxicam capsules. The average content of two
different brands of piroxicam is 97.4 and 98.5% (n = 3), which complies with
the USP 26 (92.5- 107.5%). Under the stress condition (refluxing with 0.1 N HCI),
the percentages of piroxicam decrease from 100% (0 h) to 18.9% (21 h) and 2-Ap
increase from 0% (0 h) to 63.6% (21 h)
Allelopathic potential and systematic evaluation of secondary compounds in extracts from roots of Canavalia ensiformis by capillary electrophoresis
Capillary Electrophoresis of Tropane Alkaloids and Glycoalkaloids Occurring in Solanaceae Plants
This chapter examines the role of capillary electrophoresis (CE) in the separation of tropane alkaloids, glycoalkaloids, and closely related compounds that have either pharmaceutical value or toxicological effects on humans. The latest significant developments in CE analysis have been selected and critically discussed. When the conventional CE mode was found unable to provide an acceptable selectivity towards the analytes, the addition of either an organic solvent, a chiral selector, or a surfactant to the running buffers was exploited. Likewise, nonaqueous CE (NACE) was also employed to increase solute solubilities and for a better compatibility of this media with mass spectrometry. It turns out that, upon selecting the most appropriate experimental conditions, the CE separation of tropane alkaloids and steroidal glycoalkaloids of Solanaceae plants was successfully accomplished. All major steps involved in the separation and detection of these secondary metabolites in complex samples are described and the relevant aspects of each application are examined with emphasis on the main aspects entailed a typical assay. More applications have yet to be developed in order to encourage more labs to exploit the tremendous potential of capillary electrophoresis