The development and validation of an LC-MS/MS method for the quantification of CZ112, a prodrug of 9-Nitrocamptothecin in rat plasma

Green root cultures for enhanced production of camptothecin in Pyrenacantha volubilis Hook

The roots of Pyrenacantha volubilis contain camptothecin (CPT), a high-value bioactive compound possessing anticancer and anti-HIV properties. Isolated root cultures of P. volubilis established in half MS media fortified with 0.3 mgL^-1 indole-3-acetic acid and 0.2 mgL^-1 indole-3-butyric acid and transferred to light conditions resulted in induction of green roots which obtained a maximum biomass content of 1.09 ± 0.03 g fresh weight with a growth index of 2.07 ± 0.02 in 60 days. The chlorophyll and camptothecin content of the roots was found to increase throughout the culture period attaining a maximum total chlorophyll content of 2.97 ± 0.004 mgg^-1 fresh weight in 60 days and CPT content of 2.59 ± 0.02 mgg^-1dry weight in 50 days. In the elicitation studies, the green roots treated with 200 mgL^-1 yeast extract yielded a maximum camptothecin content of 5.3 ± 0.40 mgg^-1 dry weight in 7 days of incubation, which was a 1.94 fold increase in camptothecin content than the control cultures. The thin layer chromatography, high performance liquid chromatography, and liquid chromatography-mass spectroscopy analysis further confirmed the presence of camptothecin (2.17 ± 0.04 mgg^-1DW) in the 30 day old in vitro root samples. The overall results suggest the feasibility of green root cultures of P. volubilis as an efficient system for sustainable in vitro production of camptothecin provided further scaling up experiments in bio reactors are imperative.

Determination of Scopolamine Distribution in Plasma and Brain by LC-MS/MS in Rats

Scopolamine, as a tropane alkaloid found in plants such as belladonna and datura, is used clinically as a transdermal patch and is highly neurotoxic. This study aimed to develop a simple, sensitive, and selective LC-MS/MS method for the determination of the content and distribution of scopolamine in rat plasma and brain after drug administration. In our study, sample pretreatment consisted of protein precipitation with acetonitrile followed by nitrogen blow concentration. Gradient elution of scopolamine and internal standard was performed on a ZORBAX Eclipse Plus C18 (2.1 $\ast$ 100 mm, 3.5 μm) column with water containing 0.1% formic acid (v/v) and acetonitrile as a mobile phase. Those samples were quantified in ESI positive ion mode using an API 4000 triple quadrupole mass spectrometer. The results showed that scopolamine was linear in the calibration range of 2–2500 ng/mL, and the selectivity, accuracy, precision, matrix effect, stability, and recovery of the method were within acceptable limits. The method has been validated and has been successfully used for toxicokinetic studies of scopolamine. After intraperitoneal injection, the time to peak toxic concentrations of scopolamine in rats was 0.5 h. The concentrations of scopolamine in the hippocampus and cortex were much higher than those in the striatum, indicating that the likely targets of its neurotoxic damage were the hippocampus and cortex. Overall, this study provides the basis for the neurotoxicity of scopolamine and provides a reference for its toxicokinetic studies.

Establishment of LC-MS/MS method for determination of aloperine in rat plasma and its application in preclinical pharmacokinetics

Aloperine, a novel natural active alkaloid derived from Sophora alopecuroides L., has attracted much attention for its anti-inflammatory, antiviral, anti-tumor, anti-allergy and other pharmacological activities. In this study, we first established and validated an efficient and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of aloperine in rat plasma. Cytisine was used as the internal standard (IS). The separation of aloperine and IS was conducted on a Phenomenex Luna Omega Polar C18 column (2.1 × 50 mm, 1.6 μm) with 0.3% (v/v) formic acid aqueous (containing 5 mM ammonium acetate) and 0.3% (v/v) formic acid acetonitrile using isocratic elution condition at a flow rate of 0.20 mL/min. Aloperine and IS were determined under the transitions of m/z 233.2 → 98.1 and m/z 191.2 → 148.2 (positive ionization mode), respectively. The calibration curve of aloperine was established in the range of 5 (LLOQ) to 2000 ng/mL (r2 = 0.994). The well validated method was full compliance with the bioanalytical method validation of FDA, and was applied to the pharmacokinetic study of aloperine in Sprague-Dawley rats after 50 mg/kg oral administration and 5 mg/kg intravenous injection. This study provides valuable references for the further study of Sophora alopecuroides L., especially for the drug development and clinical application of aloperine.