Simple column-switching HPLC method for determining levels of the antifungal agent micafungin in human plasma and application to patient samples

2012 ◽  
Vol 27 (5) ◽  
pp. 551-555 ◽  
Author(s):  
Saori Nakagawa ◽  
Naoko Kuwabara ◽  
Hikaru Kobayashi ◽  
Sadahiko Shimoeda ◽  
Shin Ohta ◽  
...  

2020 ◽  
Vol 20 (13) ◽  
pp. 1053-1059
Author(s):  
Mahmoud M. Sebaiy ◽  
Noha I. Ziedan

Background: Allergic diseases are considered as the major burden on public health with increased prevalence globally. Histamine H1-receptor antagonists are the foremost commonly used drugs in the treatment of allergic disorders. The target drug in this study, loratadine, belongs to this class of drugs and its biometabolite desloratadine which is also a non-sedating H1 receptor antagonist with anti-histaminic activity being 2.5 to 4 times greater than loratadine. This study aimed to develop and validate a novel isocratic Reversed-phase High-Performance Liquid Chromatography (RP-HPLC) method for rapid and simultaneous separation and determination of loratadine and its metabolite, desloratadine in human plasma. Methods: The drug extraction method from plasma was based on protein precipitation technique. The separation was carried out on a Thermo Scientific BDS Hypersil C18 column (5μm, 250 x 4.60 mm) in a mobile phase of MeOH: 0.025M KH2PO4 adjusted to pH 3.50 using orthophosphoric acid (85: 15, v/v) at an ambient temperature. The flow rate was maintained at 1 mL/min and maximum absorption was measured using the PDA detector at 248 nm. Results: The retention times of loratadine and desloratadine in plasma samples were recorded to be 4.10 and 5.08 minutes, respectively, indicating a short analysis time. Limits of detection were found to be 1.80 and 1.97 ng/mL for loratadine and desloratadine, respectively, showing a high degree of sensitivity of the method. The method was then validated according to FDA guidelines for the determination of the two analytes in human plasma. Conclusion: The results obtained indicate that the proposed method is rapid, sensitive in the nanogram range, accurate, selective, robust and reproducible compared to other reported methods.



Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3789
Author(s):  
Mohammad Hailat ◽  
Israa Al-Ani ◽  
Mohammed Hamad ◽  
Zainab Zakareia ◽  
Wael Abu Dayyih

In the current work, a simple, economical, accurate, and precise HPLC method with UV detection was developed to quantify Favipiravir (FVIR) in spiked human plasma using acyclovir (ACVR) as an internal standard in the COVID-19 pandemic time. Both FVIR and ACVR were well separated and resolved on the C18 column using the mobile phase blend of methanol:acetonitrile:20 mM phosphate buffer (pH 3.1) in an isocratic mode flow rate of 1 mL/min with a proportion of 30:10:60 %, v/v/v. The detector wavelength was set at 242 nm. Maximum recovery of FVIR and ACVR from plasma was obtained with dichloromethane (DCM) as extracting solvent. The calibration curve was found to be linear in the range of 3.1–60.0 µg/mL with regression coefficient (r2) = 0.9976. However, with acceptable r2, the calibration data’s heteroscedasticity was observed, which was further reduced using weighted linear regression with weighting factor 1/x. Finally, the method was validated concerning sensitivity, accuracy (Inter and Intraday’s % RE and RSD were 0.28, 0.65 and 1.00, 0.12 respectively), precision, recovery (89.99%, 89.09%, and 90.81% for LQC, MQC, and HQC, respectively), stability (% RSD for 30-day were 3.04 and 1.71 for LQC and HQC, respectively at −20 °C), and carry-over US-FDA guidance for Bioanalytical Method Validation for researchers in the COVID-19 pandemic crisis. Furthermore, there was no significant difference for selectivity when evaluated at LLOQ concentration of 3 µg/mL of FVIR and relative to the blank.





Author(s):  
Aruna G. ◽  
Bharathi K ◽  
Kvsrg Prasad

Objective: To develop and validate a modified isocratic reversed-phase high performance liquid chromatographic (RP-HPLC) method for determination of cilnidipine and nebivolol in human plasma to be used for pharmacokinetic studies.Methods: The drug was extracted from plasma samples by direct protein precipitation technique using acetonitrile. Amlodipine was used as internal standard (IS). Samples were analyzed on BDS C18 column (250 x 4.6 mm, 5 µm), applying ortho phosphoric acid (0.1%): Acetonitrile, at a ratio of 45:55 v/v in isocratic mode as a mobile phase at a flow rate of 1 ml/min to attain adequate resolution. Separations were performed at room temperature and monitored at a wavelength of 260 nm after injection of 50μl samples into the HPLC system. The analytical method was validated according to FDA bioanalytical method validation guidance. The method was applied for pharmacokinetic study of cilnidipine and nebivolol tablets-10 mg and 5 mg were administered as a single dose to 6 healthy male rabbits under fasting condition. Twelve blood samples were withdrawn from each rabbit over 24 h periods. From the plasma concentration-time data of each individual, the pharmacokinetic parameters; Cmax, Tmax, AUC0-t and AUC0-∞ were calculated.Results: A peak area was obtained for cilnidipine and nebivolol at 3.943 and 4.719 min retention time respectively. Linearity was established at a concentration range of 0.20-20 μg/ml (r2=0.999, n=8) for cilnidipine and 0.02-2 μg/ml (r2=0.999, n=8) for nebivolol. The lower limit of quantitation (LLOQ) was identifiable and reproducible at 0.2μg/ml for cilnidipine and 0.02 μg/ml for nebivolol. The coefficients of variation (%cv) of the intra-day and inter-day precision of cilnidipine at 600, 1000 and 1600ng/ml levels were found to be 6.90%, 6.19%, 5.22%; and 7.74%, 6.54%, 5.77%, respectively, which are lower than the accepted criteria limits (15-20 %). The mean recovery (%) cilnidipine at 600, 1000, and 1600ng/ml was found to be 101.03%, 99.27% and 104.87%, and for nebivolol 60, 100, and 160 ng/ml was found to be 106.13%, 107.03% and 98.06% respectively. Stability at different conditions and in autosampler was also established. The mean pharmacokinetic parameters; Cmax, Tmax, AUC0-t and AUC0-∞ were 6 ng/ml, 2 hr, 96.76 mg. hr/ml, 63.45 mg. hr/ml for cilnidipine and 5.8ng/ml, 2hr, 74.78 mg. hr/ml, 100.25 mg. hr/ml for nebivolol respectively.Conclusion: The present analytical method was found to be specific, sensitive, accurate and precise for quantification of cilnidipine and nebivolol in human plasma. It can be successively applied for pharmacokinetics, bioavailability and bioequivalence studies.



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