Validation of R/S-Warfarin Analysis Method in Human Blood Plasma Using HPLC with Fluorescence Detection and its Application to Patient Samples.

Context: Warfarin is extensively used for venous thromboembolism and other coagulopathies. In clinical settings, warfarin is administered as a mixture of S-warfarin and R-warfarin, and both enantiomers are metabolized by multiple cytochrome P450 enzymes into many hydroxylation metabolites. Validation of analysis method and estimation of warfarin plasma levels are important, especially in narrow-index drugs such as warfarin. Aims: This study aimed to obtain a validated method for analyzing warfarin in patient plasma according to the European Medicines Agency (EMA) guidelines. Materials and Methods: A total of 77 patients were enrolled in this study. Five millimeters of venous blood was collected using sodium ethylenediaminetetraacetic acid (EDTA) tubes for pharmacokinetic analysis. Samples were prepared by the protein precipitation technique using acetonitrile. The optimum conditions for the analysis of warfarin in human plasma were tested using fluorescence detector (FLD) high-performance liquid chromatography (HPLC) with Chiralcel OD-RH column (4.6 × 150 mm i.d., 5 µm), Chiralcel OD-RH guard column (4.0 × 10 mm, 5 µm), and a column temperature of 45°C. The mobile phase used was acetonitrile: phosphate buffer pH 2 (40:60), with an isocratic flow rate of 1 ml/min and an injection volume of 20 µl. Excitation and emission wavelengths were 310 and 350 nm (warfarin) and 300 and 400 nm (griseofulvin). The retention time of griseofulvin was 6-7.5 minutes; R-warfarin was 10-11.5 minutes; and S-warfarin was 14-16 minutes. Results: The result of this validation obtained the optimum conditions. This method yielded the limit of detection (LOD) values of 0.0674 ppm (R-warfarin) and 0.0897 ppm (S-warfarin). The limit of quantification (LOQ) values were 0.225 ppm (R-warfarin) and 0.298 ppm (S-warfarin). Linearity existed at concentrations of 0.2-3 ppm with the line equation y = 0.0705x + 0.0704 with R² = 0.978 for R-warfarin and y = 0.0513x + 0.0297 with R² = 0.9924 for S-warfarin. At least 75% of the seven concentrations met the reverse concentration requirements, which were below ± 15%. This method met the requirements of accuracy and precision within and between runs, selectivity, and carryover where the %RSD and %diff values were below ± 15%. The mean plasma concentrations of R-warfarin and S-warfarin were found to be 0.76 ± 1.87 (SD) µg/ml and 0.59 ± 0.81 (SD) µg/ml, respectively. The mean standard dose group plasma concentration from the analysis of 77 samples was 0.68 ± 0.61 µg/mL for R-warfarin and 0.52 ± 0.42 µg/mL for S-warfarin. Conclusions: Based on these results, this analytical method can be declared valid and can be used for sample measurement in warfarin pharmacokinetic studies.

Validation of bioanalytical method for quantification of Vitamin K2 (MK-4) in human plasma by high-performance liquid chromatography-ultraviolet.

Vitamin K can reduce warfarin's anticoagulant action, causing a variance in response among individuals taking warfarin. Vitamin K comes in two forms, namely Vitamin K1 (phylloquinone) and K2 (menaquinones). Menaquinone-4 (MK-4) is a kind of Vitamin K2 found in meat and dairy products. Analysis of MK-4 levels in human plasma is very useful for patients who receive warfarin therapy. High-performance liquid chromatography (HPLC) can be used for warfarin's bioanalysis, and it must be validated. The purpose of this study was to validate the bioanalytical method for quantification of Vitamin K2 (MK-4) in human plasma according to the 2019 European Medicines Agency (EMA) guideline. Vitamin K2 (MK-4) was extracted using acetonitrile. HPLC with an ultraviolet detector at 245 nm, using a T3 column set at 30°C and an isocratic mobile phase containing methanol: phosphate buffer (95:5) at pH 3, a flow rate of 1 mL/min was used in this study. The warfarin concentration of 0.5-3 µg/mL was used. About 5.50%-17.42% and 6.18%-8.74%, respectively, were the average ranges of percentage coefficient of variation and percentage difference. There was no response at the analyte's retention time in the six blank plasmas and at the analyte's retention time in the blank after the injection of upper limit of quantification, indicates that the procedure was very selective and did not result in any carryover. This bioanalytical method fulfills the parameters of selectivity, accuracy, precision, and carryover based on the 2019 EMA guidelines.

Preparation and molecular interaction of organic solvent-free piperine pro-liposome from soy lecithin.

Pro-liposome is a type of drug delivery system (DDS) with numerous advantages as a stable material with various applicability for several pharmaceutical dosage forms, to effectively deliver the material to reach its target in the human body. Nevertheless, it is mostly designed by employing an organic solvent hence giving rise to safety issues. We have developed a method for the preparation of organic solvent-free liposomes composed of soy lecithin and cholesterol by highlighting the importance of temperature during the initial mixing process, a self-hydration of a thin layer spread film, and a spray-drying technique with a suitable excipient as the carrier. The method was successfully applied to prepare a stable pro-liposome containing 0.17% (w/w) of piperine with an encapsulation efficiency of 95.58 ± 2.91%. Moreover, the study revealed that a piperine molecule forms hydrophobic interaction with six of the adjacent phospholipids in the liposome structure, this information can be useful for researchers designing similar studies. In conclusion, organic solvent-free pro-liposome can be an alternative method in the development of DDS, and several factors could be continuously improved to fulfill the intended pro-liposome characteristic.

Evaluation of adverse drug reaction in patients warfarin therapy.

This research aimed to understand the adverse drug reaction (ADR) in heart disease outpatients who were administered warfarin at a hospital in Bandung city. The research was conducted using a cross-sectional design with an observational approach. Subsequently, data were collected from 74 patients who met the inclusion criteria. The causality assessment was made by the Naranjo Algorithm and the incidence of bleeding was classified based on the Bleedscore™. The result showed that the most common ADR were nausea, dizziness, stomach ache, ecchymosis, petechiae, bleeding in the mouth, melena, etc. Furthermore, the INR value was the most significant factor in the incidence of ADR. It was 6.445 using a value of P = 0.001 or a confidence interval of 95%. The most common side effect of warfarin in cardiac outpatients was superficial bleeding, followed by internal bleeding (melena). The INR value is the most significant factor in measuring the incidence of ADR.

An Integrated Process for the Xylitol and Ethanol Production from Oil Palm Empty Fruit Bunch (OPEFB) Using Debaryomyces hansenii and Saccharomyces cerevisiae.

Oil palm empty fruit bunch (OPEFB) is the largest biomass waste from the palm oil industry. The OPEFB has a lignocellulose content of 34.77% cellulose, 22.55% hemicellulose, and 10.58% lignin. Therefore, this material's hemicellulose and cellulose content have a high potential for xylitol and ethanol production, respectively. This study investigated the integrated microaerobic xylitol production by Debaryomyces hansenii and anaerobic ethanol semi simultaneous saccharification and fermentation (semi-SSF) by Saccharomyces cerevisiae using the same OPEFB material. A maximum xylitol concentration of 2.86 g/L was obtained with a yield of 0.297 g/gxylose. After 96 h of anaerobic fermentation, the maximum ethanol concentration was 6.48 g/L, corresponding to 71.38% of the theoretical ethanol yield. Significant morphological changes occurred in the OPEFB after hydrolysis and xylitol and ethanol fermentation were shown from SEM analysis.

Validation of warfarin enantiomer analysis method in plasma using high-performance liquid chromatography fluorescence detector.

Warfarin (WF) is an anticoagulant commonly used for thromboembolism-related diseases. This study aims to assess the pharmacokinetic profile of WF. The stereospecific interaction of S-and R-WF requires quantification of the enantiomer to determine the pharmacokinetic profile. The analysis method of the enantiomers in plasma is developed using an HPLC fluorescence detector with a Chiralcel OD-RH column (4.6 mm × 150 mm i.d., 5 m) and a Chiralcel OD-RH guard column (4.0 mm × 10 mm, 5 m). The separation is conducted using isocratic with acetonitrile mobile phase: Phosphate buffer, pH 2.00 (40:60 v/v), column temperature 40°C, flow rate 1 mL/min, injection volume 50 L. WF is measured at an excitation wavelength of 310 nm and emission of 350 nm. This method results in limit of detection (LOD) values of 18.6 ng/mL and limit of quantitation (LOQ) of 62.01 ng/mL for R-WF and LOD values of 18.61 ng/mL and LOQ of 62.04 ng/mL for S-WF. The results showed a linearity in concentration between 100 and 2500 ng/mL with r 2 = 0.9969 and r 2 = 0.9991 for R-and S-WF. The validation requirements of selectivity, accuracy, and precision for within and between run with a value of <15% for % relative standard deviation and % diff were achieved. This method can be used in the sample measurement of WF pharmacokinetic studies.

Characteristic Comparison of an Intraoral Thin Film Containing Astaxanthin Nanoemulsion Using Sodium Alginate and Gelatin Polymers

Objectives: The present study was conducted to compare the characteristics of a thin film containing an astaxanthin-loaded nanoemulsion (TFANE) using two kinds of natural polymers, namely sodium alginate and gelatin. Materials and Methods: An astaxanthin nanoemulsion was prepared by using the self-nanoemulsifying method, followed by incorporation into a polymer matrix system by the solvent casting method to form TFANE. A characteristic comparison between the sodium alginate and gelatin matrix systems was carried out by comparing the physical and mechanical film properties. At the end of the study, in vitro dissolution tests were also assessed. Results: An intraoral film with good physical and mechanical properties containing an astaxanthin-loaded nanoemulsion was developed successfully using a natural polymer matrix system. The film, made from a gelatin matrix system containing an astaxanthin nanoemulsion, was more flexible and harder than films made from a sodium alginate matrix system, where all of the films have ideal characteristics for intraoral delivery. The dissolution test results showed that, with both sodium alginate and gelatin, more than 90% of the drug was released at 15 minutes. Conclusion: Gelatin as a natural polymer appears to be promising for the preparation of an intraoral thin film delivery system.