Improved assay for determination of busulfan by liquid chromatography using postcolumn photolysis

Stability-Indicating Method Development and Validation for Busulfan Drug Substance by Gas Chromatography-Flame Ionization Detector

A new, simple and stability-indicating gas chromatography-flame ionization detection (GC-FID) method was developed and validated for the quantitative determination of busulfan and its organic impurities (OI) in drug substance without derivatization. The chromatographic attributes were achieved on a fused silica capillary column (0.53 mm × 30 m, 1.0 μm, USP Phase G42), using hydrogen as a carrier gas with a split ratio of 1:1. Forced degradation studies were conducted to establish the stability-indicating capability and method specificity that showed the stressed busulfan peak was free from any co-elution. Robustness study demonstrated the chromatograms remained mostly unaffected under deliberate, but small variations of chromatographic parameters, establishing the reliability of the method during routine usage. The method was shown to be reliable, sensitive, specific, linear, accurate, precise and rugged in the 1,4-butanediol concentration range of 1-20 μg/mL. The method, intended for compendial uses, is suitable for quantitative analysis of busulfan and its organic impurities in drug substances.

Antineoplastic drugs and their analysis: a state of the art review

We provide an overview of the analytical methods available for the quantification of antineoplastic drugs in pharmaceutical formulations, biological and environmental samples.

Analysis of anticancer drugs: a review

In the last decades, the number of patients receiving chemotherapy has considerably increased. Given the toxicity of cytotoxic agents to humans (not only for patients but also for healthcare professionals), the development of reliable analytical methods to analyse these compounds became necessary. From the discovery of new substances to patient administration, all pharmaceutical fields are concerned with the analysis of cytotoxic drugs. In this review, the use of methods to analyse cytotoxic agents in various matrices, such as pharmaceutical formulations and biological and environmental samples, is discussed. Thus, an overview of reported analytical methods for the determination of the most commonly used anticancer drugs is given.

Near infrared spectroscopy and process analytical technology to master the process of busulfan paediatric capsules in a university hospital

The prescription of unlicensed oral medicines in paediatrics leads the hospital pharmacists to compound hard capsules, such as busulfan, an alkylating agent prescribed in preparative regimens for bone marrow transplantation. In this study, we have investigated how the general principle of process analytical technology (PAT) can be implemented at the small size of our hospital pharmacy manufacturing unit. Near infrared spectroscopy (NIRS) was calibrated for raw material identification, blend uniformity analysis and final content uniformity of busulfan hard capsules of 11 different strengths. Measurements were performed on capsules from 2 to 40 mg (n=440). After optimisation, accuracy and linearity of the NIRS quantitative method was demonstrated after comparison with a previously validated quantitative high performance thin layer chromatography (HPTLC) method. Such a comparison led to attractive NIRS precision: +/-0.7 to +/-1.0 mg for capsules from 2 to 40 mg, respectively. As NIRS is a rapid and non-destructive technique, the individual control of a whole batch of busulfan paediatric capsules intended to be administrated is possible. Actually, mastering the process of busulfan paediatric capsules with the NIRS integrated into the notion of PAT is a powerful analytical tool to assess the process quality and to perform content uniformity of at least 5mg busulfan-containing capsules.

Development of a rapid and specific assay for detection of busulfan in human plasma by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry

A sensitive and specific assay for detection of busulfan in human plasma was developed. The assay is based on rapid isolation of busulfan by liquid-liquid extraction with ethyl acetate, and detection by high-performance liquid chromatography with electrospray ionization and tandem mass spectrometry. 1,6-Bis(methanesulfonyloxy)hexane, a synthesized analogue of busulfan, was used as the internal standard (IS). The acquisition was performed in the multiple reaction monitoring mode; busulfan and the IS were detected with no interferences from plasma matrix. The method was linear over the range 5-2500 ng mL(-1), with r2 > 0.99 and a run time of only 3.5 min. The intra- and inter-assay precisions were in the ranges 2.1-11.9% and 3.2-10.1%, respectively, and the intra- and inter-assay accuracies were 92.2-107.6% and 94.7-104.1%, respectively. The absolute recoveries were 82.0% (20 ng mL(-1)), 90.6% (1000 ng mL(-1)) and 80.0% (2000 ng mL(-1)) for busulfan, and 89.1% for the IS (1000 ng mL(-1)). The limits of detection and quantification were 2 and 5 ng mL(-1), respectively. The validated method was successfully applied to analyze plasma samples obtained from six adults receiving doses of 1 mg kg(-1) in a conditioning regimen prior to bone marrow transplantation. A marked intra-patient variation in busulfan concentrations during the steady state was observed, which limits the application of pharmacokinetic modeling and suggests that continuous therapeutic monitoring is necessary for adequate individualized dosing. In this regard, the present assay brings important advantages relative to other methods described in the literature, i.e., it is highly specific and simple to perform, with a rapid chromatographic run time (3.5 min), and the whole procedure can be completed in 4-5 h, which would permit dose corrections after the third dose allowing earlier and better dosing adjustments towards the target level of busulfan.