Selective and sensitive determination of pamidronate in human plasma and urine by gas chromatography with flame photometric detection

Abstract

A rapid, selective and sensitive method for the determination of pamidronate in human plasma and urine samples by gas chromatography (GC) has been developed. After deproteinization of the sample with trichloroacetic acid, pamidronate was converted into its N-isobutoxycarbonyl methyl ester derivative and measured by GC with flame photometric detection (FPD), using a HP-1 capillary column. The derivative preparation and GC analysis were accomplished within 30 min. The derivative was sufficiently volatile and stable, giving a single and symmetrical peak, and provided an excellent FPD response. The detection limit of pamidronate, at a signal-to-noise ratio of 3, was ca. 100 pg injected, and the calibration curve for this compound in the range 20-1000 ng was linear and sufficiently reproducible for quantitative determination. This method could be successfully applied to plasma and urine samples without a preliminary clean-up except for deproteinization with trichloroacetic acid, and pamidronate could be measured without any influence from coexisting substances. Overall recoveries of pamidronate added to plasma and urine samples were 93-97%. The coefficients of variation for intra-assay and inter-assay of pamidronate in these samples were 1.0-7.9% (n = 3) and 4.1-8.3% (n = 6), respectively.

A general approach for the quantitative analysis of bisphosphonates in human serum and urine by high‐performance liquid chromatography/tandem mass spectrometry

“…Since most bisphosphonates lack chromophores, their derivatization with UV or fluorescent active reagents, such as 2,3‐naphthalene dicarboxyaldehyde4, 11 and 9‐fluorenylmethyl chloroformate,8 and the formation of complexes with Cu(II),12 Al(III)‐morin,13 and Fe(III),14, 15 have been used in high‐performance liquid chromatography (HPLC) methods to enhance the sensitivity of detection. For gas chromatography (GC) or GC/mass spectrometry (MS) methods, the bisphosphonates were converted into volatile derivatives by acylation and silylation 9, 16, 17…”

Demineralization Removes Residual Alendronate in Allograft Bone Procured From Donors With a History of Bisphosphonate Use

“…Calcium was removed by ion‐exchange chromatography and discarded to isolate bisphosphonates. The amine moiety of alendronate was derivatized with isobutylchloroformate, cleaned, extracted, and concentrated 14 . This concentrate was methylated with diazomethane to form phosphoric acid methyl esters.…”

Solid-phase extraction and validated spectrofluorimetric quantification of pamidronate in human plasma

“…Moreover, they are extremely polar, on account of numerous functional groups, and they are not appreciably retained on HPLC columns [4]. Most of the methods applied for the quantification of PAM belong to the categories of liquid chromatography [5][6][7] and gas chromatography [8].…”