Simple high-performance liquid chromatography method for the simultaneous determination of ketoconazole and piperine in rat plasma and hepatocyte culture

HSPiP and QbD Program-Based Analytical Method Development and Validation to Quantify Ketoconazole in Dermatokinetic Study

Ketoconazole (KTZ) is the most potential azole anti-mycotic drug. The quantification of KTZ from various layers of the skin after topical application of lipidic nanocarriers is critical. We addressed a sensitive, specific, simple, rapid, reproducible, and economic analytical method to quantify KTZ from the treated skin homogenate using the Hansen solubility parameter (HSP, HSPiP software)-based modeling and experimental design. The software provided various HSP values for KTZ and solvents to compose the mobile phase. The Taguchi model identified the significant sets of factors to develop a robust bioanalytical method with reduced variability. In the optimization, acetonitrile (ACN) concentration (X1 as A) and the pH of mobile phase (X2 as B) were two factors against two responses (Y1: peak area and Y2: retention time). The HPLC (high-performance liquid chromatography) method validation was carried out based on US-FDA guidelines for the developed KTZ formulations (suspension, solid nanoparticles, and commercial product) extracted from the treated rat skin. The experimental solubility of KTZ was found to be maximum in the two solvents (ACN and ethyl acetate), based on HSP values. Surface response methodology (SRM) identified remarkable impact of ACN concentration and the mobile phase pH on the peak area and retention time. Analytical limits (0.17 and 0.50 µg/mL) were established for KTZ-SLNs (extracted from the skin). The method was implemented with high reproducibility, accuracy, and selectivity to quantify KTZ from the treated rat skin.

A New Strategy for the Software-Assisted LC Separations of Ketoconazole and Its Impurities

Analytical quality by design and the use of dissimilar chromatographic systems can be employed to accelerate chromatographic separations. Herein, a software (S-Matrix)-assisted platform was used to proficiently screen, optimize and select the optimal parameters for the chromatographic separation of ketoconazole and its related impurities. This approach evaluated the various chromatographic parameters in a stepwise manner based on the statistical tools and provided an in-depth understanding of the critical parameters influencing the peak selectivities and separations. It was demonstrated that dissimilar conditions, such as different stationary phases, mobile phase pH and organic modifiers (i.e., critical method variables), can improve the peak resolution, while the critical quality attributes can provide conditions appropriate for quantification purposes via a quality target analytical method. Furthermore, an orthogonal method was established to support the primary method. The orthogonality between the two methods was defined by the correlation matrix between the two systems using the Pearson correlation coefficient and was found to be 0.12. Using the optimized method, the primary method was validated as per International Council for Harmonization in the range of 0.05-1.0% for impurities and 80.0-120.0% for ketoconazole, thereby indicating the suitability of the method for use in quality control laboratories.

Analysis of curcumin and piperine in biological samples by reversed-phase liquid chromatography with multi-wavelength detection

Widely accessible food phytochemicals such as curcumin have been reported to have anti-inflammatory and anticarcinogenic properties. However, curcumin has poor absorption in the gut, and piperine has been of interest as a dietary compound that can enhance curcumin bioavailability. The aim of this study was to develop and optimize a technique using reversed-phase chromatography with multi-wavelength detection for the simultaneous measurement of curcumin and piperine in various biological matrices. Emodin was used as an internal standard. Protein precipitation and liquid-liquid extraction based on acetonitrile provided good recovery of these analytes. A 150 mm × 4.6 mm I.D. Luna C18 column was used under isocratic conditions to separate curcumin, piperine, and emodin with baseline resolution, and with good separation from other sample components, in as little as 4 min. The detection limits for curcumin and piperine were 3 and 7 ng/mL, respectively. This method has been used to quantitate these compounds in samples such as human intestinal epithelial cell lysates and mouse plasma or GI tissues in research aimed at examining the bioavailability of curcumin in the presence of piperine.

Colloidal lipid nanodispersion enriched hydrogel of antifungal agent for management of fungal infections: Comparative in-vitro, ex-vivo and in-vivo evaluation for oral and topical application

Ketoconazole (KZ) is broad spectrum antifungal drug, used for the treatment of fungal infections. KZ's clinical topical use has been associated with some adverse effects in healthy adults particularly local reactions, such as stinging, severe irritation, and pruritus. However, bioavailability of KZ after oral administration is low from tablets due to its low aqueous solubility. The objective of this investigation was development and characterization of KZ-containing solid lipid nanoparticles (KZ-SLNs) and SLN-containing hydrogel (KZ-SLN-H) for oral and topical delivery of KZ. KZ-SLNs were prepared using homogenization-sonication method. Optimal KZ-SLN formulation was selected based on physicochemical and in-vitro release studies. Optimized KZ-SLN converted to KZ-SLN hydrogel (KZ-SLN-H) using gelling polymers and optimized with rheological and in-vitro studies. Further, optimized KZ-SLN and KZ-SLN-H formulations evaluated for crystallinity, morphology, stability, ex-vivo and in-vivo pharmacokinetic (PK) studies in rats, comparison with KZ suspension (KZ-S) and KZ-S hydrogel (KZ-SH). Optimized KZ-SLN formulation showed desirable characters. KZ-SLN and KZ-SLN-H formulations exhibited spherical shape, converted to amorphous, sustained release behaviour and enhanced permeability (p < 0.05). Moreover, both formulations were stable for three months at 4 °C and 25 °C. PK studies revealed 1.9 and 1.5-folds, 3.5 and 2.8-folds enhancement of bioavailability of optimized KZ-SLN and KZ-SLN-H formulations (p < 0.05) compared with KZ-S and KZ-SH formulations, respectively. Overall, SLN and SLN-H formulations could be considered as an efficient delivery vehicles for KZ through oral and topical administration for better control over topical and systemic fungal infections.

Effect of neat and binary vehicle systems on the solubility and cutaneous delivery of piperine

Vitiligo is a skin disease characterized by depigmentation disorders due to lack of melanin production. Piperine, an alkaloid extracted from black piper, is active in melanocytes proliferation. To achieve this, the drug has to reach the melanocytes which exist in the deep layer of the epidermis. Higher drug concentration can be obtained after application of optimized formulation to skin. Accordingly, the aim of this work is to investigate the effect of vehicles on skin penetration of piperine as the first step in development of optimized formulation. The tested vehicles include ethanol (Eth), propylene glycol (PG), polyethylene glycol 400 (PEG), and oleic acid (OA) and their combinations. Water was used as the control and skin permeation was monitored using rabbit ear model skin. The highest piperine solubility (48.6 mg/ml) and flux (40.8 μg/cm² h) was achieved by Eth and the lowest piperine flux (1.17 μg/cm² h) was reported for PEG. PG and OA showed piperine flux values comparable to that of the control. Among different combination systems, Eth-OA (75:25) binary system had the highest piperine flux (59.3 μg/cm² h) followed by Eth-OA (50:50) (32.3 μg/cm² h) and PG-OA (90:10) (22.7 μg/cm² h). The study thus introduced a vehicle system as the first step in the development of topical formulation of piperine.

LC-HRMS determination of piperine on rat dried blood spots: A pharmacokinetic study

A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed and validated for the determination of piperine (PPR) on dried blood spots (DBS). DBS samples were prepared by spiking the whole blood with analyte to produce 30 µL of blood spots on specimen collection cards. Chromatographic separation was achieved on an Atlantis dC₁₈ column using acetonitrile and water (0.1% formic acid) (85:15, v/v) as mobile phase in an isocratic mode of elution at a flow rate of 0.75 mL/min. MS detection was carried out in electrospray positive ion mode for the target ions and monitored at m/z 286.1465 for PPR and 272.1303 for the internal standard (IS). The developed method exhibited a linear dynamic range over 0.01-2000 ng/mL for PPR on DBS. The overall extraction recovery of PPR from DBS was 92.5%. Influence of hematocrit and spot volume on DBS was also evaluated and found to be well within the acceptable limits. The method was successfully applied to pharmacokinetic studies of PPR in rats.

Stability-Indicating Validated Novel RP-HPLC Method for Simultaneous Estimation of Methylparaben, Ketoconazole, and Mometasone Furoate in Topical Pharmaceutical Dosage Formulation

A simple, specific, precise, and accurate RP-HPLC method has been developed and validated for simultaneous estimation of Methylparaben (MP), Ketoconazole (KT), and Mometasone Furoate (MF) topical pharmaceutical dosage formulation. The separation was achieved by Waters X Terra C18 column using mobile phase consisting of buffer (triethyl amine in water, pH adjusted to 6.5 with glacial acetic acid)-acetonitrile (40 : 60, v/v) at a flow rate of 1.5 mL/min and detection at 250 nm. The method showed linearity with correlation coefficient <0.9999 over the range of 0.12–15.2 μg/mL, 0.67–149.4 μg/mL, and 0.42–7.6 μg/mL for MP, KT, and MF, respectively. The mean recoveries were found to be in the range of 99.9–101.1% for all the components. The method was validated as per the ICH guidelines for linearity, limit of detection, limit of quantification, accuracy, precision, robustness and solution stability. Stability indicating capability of the developed method was established by analyzing forced degradation of samples in which spectral purity of MP, KT, and MF along with separation of degradation products from analytes peak was achieved. The method can be successfully applied for routine analysis of quantitative determination of MP, KT, and MF in pharmaceutical dosage form.

Identification of major degradation products of ketoconazole

Analytical methods were developed for the identification of major degradation products of Ketoconazole, an antifungal agent. The stressed degradation of Ketoconazole drug substance was performed under acid, base, thermal, photo and oxidative stress conditions. The major degradation was observed under acid, base and oxidative stress conditions. The degradation study was performed on Inertsil ODS-3V, length 100 X diameter 4.6 mm, particle size 3 μm column using gradient method. These degradants were identified by LC-MS technique.

Simultaneous UFLC-ESI-MS/MS determination of piperine and piperlonguminine in rat plasma after oral administration of alkaloids from Piper longum L.: application to pharmacokinetic studies in rats

The alkaloids from Piper longum L. showed protective effects on Parkinson's disease models in our previous study and piperine and piperlonguminine were the two main constituents in the alkaloids. The present study aimed at developing a rapid, sensitive, and accurate UFLC-ESI-MS/MS method and validating it for the simultaneous determination of piperine and piperlonguminine in rat plasma using terfenadine as the internal standard. The analytes and internal standard (IS) were extracted from rat plasma using a simple protein precipitation by adding methanol/acetonitrile (1:1, v/v). A Phenomenex Gemini 3 u C18 column (20 mm × 2.00 mm, 3 μm) was used to separate the analytes and IS using a gradient mode system with a mobile phase consisting of water with 0.1% formic acid (mobile phase A) and acetonitrile with 0.1% formic acid (mobile phase B) at a flow rate of 0.4 mL/min and an operating column temperature of 25°C. The total analytical run time was 4 min. The detection was performed using the positive ion electrospray ionization (ESI) in multiple reaction monitoring (MRM) mode with transitions at m/z 286.1-201.1 for piperine, m/z 274.0-201.1 for piperlonguminine, and m/z 472.4-436.4 for the IS. The calibration curves were both linear (r>0.995) over a concentration range of 1.0 to 1000 ng/mL; the lower limit of quantification (LLOQ) was 1.0 ng/mL for both piperine and piperlonguminine. The intra-day and inter-day precisions (RSD %) were <12.1%, accuracies ranged from 86.6 to 120%, and recoveries ranged from 90.4 to 108%. The analytes were proven stable in the short-term, long-term, and after three freeze-thaw cycles. The method was successfully applied to pharmacokinetic studies of piperine and piperlonguminine in rats after oral administration of alkaloids from P. longum L.

Ultra-low flow liquid chromatography assay with ultraviolet (UV) detection for piperine quantitation in human plasma

A robust and sensitive ultra-low flow liquid chromatography (UFLC) method that can reproducibly, at reasonable cost, detect low concentrations of piperine from human plasma is necessary. Piperine in plasma was separated and quantified by a gradient method using ultraviolet detection at a maximal absorbance wavelength of 340 nm. An aliquot was injected onto a reversed-phase column Waters SymmetryShield, 2.1 x 100 mm, 3.5 microm, C(18) column, attached to a Waters absorbosphere, 4.6 x 30 mm, C(18) guard column and eluted with a mobile phase containing a mixture of acetonitrile/water/acetic acid (25:74.9:0.1, v/v/v) on line A and acetonitrile/acetic acid (99.9:0.1, v/v) on line B. The flow rate was 0.3 mL/min. The gradient method consisted of an opening condition of 20% pump B, with a linear increase to 37% pump B over 8 min, then a linear increase to 100% pump B at 11 min, 2 min at 100% pump B, and then a return to the opening condition (20% pump B) via a linear gradient over 2 min, followed by 5 min re-equilibration at opening conditions. The total run time was 20 min for each sample. All samples were processed protected from ambient light to avoid isomerization of piperine. The plasma assay was linear with R = 0.9995, with a lower limit of detection [signal-to-noise (S/N) > 5:1] of 100 pg of piperine loaded into the analytical system with acceptable accuracy and precision. Extraction recoveries of piperine from human plasma were 88% for quality control high (QCH), 93% for quality control medium (QCM), and 90% for quality control low (QCL), and the matrix effect was <12%. Piperine was quantifiable from a 50 mg oral dose given to human volunteers. A UFLC method for the rapid assay of human plasma with sensitivity to detect as low as 5 ng/mL piperine was developed. The method sensitivity equals that of liquid chromatography/tandem mass spectrometry (LC/MSMS) methods with much less cost.

Optimization and validation of a high-performance liquid chromatographic method with UV detection for the determination of ketoconazole in canine plasma

An isocratic high-performance liquid chromatographic method with detection at 240 nm was developed, optimized and validated for the determination of ketoconazole in canine plasma. 9-Acetylanthracene was used as internal standard. A Hypersil BDS RP-C18 column (250 mm x 4.6 mm, 5 microm particle size), was equilibrated with a mobile phase composed of methanol, water and diethylamine 74:26:0.1 (v/v/v). Its flow rate was 1 ml/min. The elution time for ketoconazole and 9-acetylanthracene was approximately 9 and 8 min, respectively. Calibration curves of ketoconazole in plasma were linear in the concentration range of 0.015-10 microg/ml. Limits of detection and quantification in plasma were 5 and 15 ng/ml, respectively. Recovery was greater than 95%. Intra- and inter-day relative standard deviation for ketoconazole in plasma was less than 3.1 and 4.7%, respectively. This method was applied to the determination of ketoconazole plasma levels after administration of a commercially available tablet to dogs.

Comparison of capillary zone electrophoresis and high performance liquid chromatography methods for quantitative determination of ketoconazole in drug formulations

A capillary zone electrophoresis (CZE) and a high-performance liquid chromatography (HPLC) method have been developed for identification and determination of ketoconazole, an imidazole antifungal, in pharmaceutical preparations. The suitabilities of both methods for quantitative determination of ketoconazole were approved through validation specification such as linearity, precision, accuracy, limit of detection and quantification. The proposed methods were used for determination of ketoconazole in commercial pharmaceutical dosage forms (tablets and creams). Under described conditions, CZE method is more selective, while the HPLC method is more sensitive. Both methods are rapid (tR(CZE)=5.14 min and tR(HPLC)=2.66 min), which is important for routine application. However, the HPLC method provides a repeatability of the quantitative analysis of ketoconazole in drug formulations below 1.5% relative standard deviation (R.S.D), while the repeatability of the CZE method is in the order of 2-3% R.S.D.

Immunotoxicological effects of piperine in mice

The immunotoxicological effects of piperine were investigated in Swiss male mice, gavaged at a dose of 1.12, 2.25 or 4.5 mg/kg body weight for five consecutive days. All the dose levels had no overt toxic effect and the liver gained weight normally. Treatment at highest dose, however, resulted in significant decrease in the weight of spleen, thymus and mesenteric lymph nodes, but not of peripheral lymph nodes. All the dose levels suppressed the cellular population of lymphoid organs, except for the spleen, where the doses of 1.12 and 2.25 caused an increase. Haematologically, doses of 2.25 and 4.5 mg/kg caused a significant reduction in total leucocyte counts and differential leucocyte counts showed an increase in the percentage of neutrophils. The higher doses of 2.25 and 4.5 mg/kg suppressed the mitogenic response of B-lymphocyte to lipopolysaccharide. The number of primary antibody (IgM) forming cells in the spleen and the level of primary antibody in serum, was decreased. The doses of 1.12 and 2.25 mg/kg suppressed the mitogenic response of T-lymphocytes to phytohaemagglutinin and the nitroblue tetrazolium (NBT) dye reducing activity of peritoneal exudate cells (PECs). Since the lowest dose of 1.12 mg of piperine per kg body weight had no immunotoxic effect, it may be considered as immunologically safe "no observed adverse effect level (NOAEL)" dose.