scholarly journals BIOAVAILABILITY ENHANCEMENT BY FLOATING MICROBALLOONS OF DIPYRIDAMOLE AND CLOPIDOGREL: IN VIVO PHARMACOKINETIC STUDY

Author(s):  
SEELAM RAMYA KRISHNA ◽  
A. RAMU ◽  
S. VIDYADHARA ◽  
A. PRAMEELA RANI

Objective: In vivo pharmacokinetic studies of clopidogrel and dipyridamole floating microballoons to check their bioavailability enhancement. Methods: The bioanalytical method development was carried by using HPLC with column Poroshell 120 EC-C 18; 4.6x100 mm. The in vivo pharmacokinetic studies were performed in Wistar male rats and the obtained data from the pharmacokinetic parameters were analyzed using PK Solver software. Results: The developed bioanalytical method was found to be linear in the concentration range of 1-100 ng/ml for clopidogrel bisulfate and 0.02-4µg/ml for dipyridamole with correlation coefficient of 0.9993 and 0.9987 respectively. The study results showed that the method was simple, linear, accurate and precise. The in vivo studies indicated that the AUC was found to be increased by 33.3% and 154.5% for clopidogrel and dipyridamole micro balloons, respectively, when compared to their pure drugs. Conclusion: The bioanalytical methods development and their validation parameters indicated that the methods are accurate, precise and linear in the studied range of concentrations. In vivo test results infer to the effective, sustained release of both the drugs when formulated as micro balloons and increase in the absorption, thereby enhancing the bioavailability of the drugs. The pharmacokinetic studies also confirmed the increase in the mean residence time of the drugs when formulated as floating microballoons.

2019 ◽  
Vol 9 (4-A) ◽  
pp. 490-496
Author(s):  
M. Suresh Babu ◽  
T. E. Gopalakrishna Murthy

The objective of this study was to investigate differences in the pharmacokinetic patterns between pure drug and an optimized  formulation of fast dissolving tablets  of Simvastatin. The formulations were administered to 2 groups of white New Zealand rabbits (n=6) following cross over design pattern and the plasma levels were measured using LC-MS/MS method. Pharmacokinetic parameters were determined for each formulation. The comparison of the plasma time curves of the dosage forms showed that each dosage form caused significant differences in the drug plasma levels.  The highest mean Cmax value was observed for optimized fast dissolving tablets (68.33 ± 0.42ng/ml) compared to  pure drug (27.72 ± 0.31ng/ml). The mean time taken to peak plasma concentration for (Tmax) following administration of pure drug  was  11.53 ± 0.011hours, while it was 6.09 ± 0.072 hour following administration of selected optimized fast dissolving tablets.The elimination rate constant (Kel) for pure drug and optimized fast dissolving tablets were found to be 0.58 ± 0.012h-1and 0.53 ± 0.014 h-1 respectively.  The absorption rate constant (Ka) for pure drug and optimized fast dissolving tablets were found to be 1.68 ± 0.01h-1and 5.53 ± 0.02h-1 respectively. The AUC0-αvalues observed with optimized fast dissolving tablets686.1.±2.07 nghr/ml in compared to pure drug values 191 ± 1.43 nghr/ml. Thus, the results of pharmacokinetic studies indicated rapid and higher oral absorption of Simvastatin when administered as its fast dissolving tablets. Both Ka and AUC were markedly increased by fast dissolving tablets. Keywords: LC-MS/MS, Simvastatin, fast dissolving, In-vivo studies, pharmacokinetic parameters.


2020 ◽  
Vol 10 (5) ◽  
pp. 6513-6521

A biowaiver means that in vivo bioavailability and/or bioequivalence studies may be waived (not considered necessary for product approval). Instead of conducting expensive and time consuming in vivo studies, a dissolution test could be adopted as the surrogate basis for the decision as to whether the two pharmaceutical products are equivalent. The biowaiver approach based on BCS is intended to replace bioequivalence in vivo studies. The aim of the study was to study dissolution kinetics of amlodipine tablets in order to assess their equivalence under conditions in vitro according to the biowaiver. The study of dissolution kinetics of drugs in the form of amlodipine tablets has been carried out in accordance with the requirements of the “biowaiver” procedure, the recommendations of the SPhU and the WHO requirements in order to assess the possibility of replacing the pharmacokinetic studies in vivo by tests in vitro. The possibility to use the recommendations of the "biowaiver" procedure for the registration of generics amlodipine tablets has been found. The studies conducted have shown that amlodipine can be referred to class І of the biopharmaceutical classification system, i.e. substances with a high biopharmaceutical solubility and a high penetration rate. It will allow conducting comparative studies in vitro to confirm the equivalence of drugs. The evaluated amlodipine drugs fulfill biowaiver criteria for drugs containing BCS Class I active pharmaceutical ingredients. Both drugs are “rapidly dissolving,” both meet the criteria of dissolution profile similarity, f2 (i.e., the dissolution profile of the test product is similar to that of the reference product in pH 1.2, 4.5, and 6.8 buffers using the paddle method at 75 rpm), and both are considered to be in vitro equivalent without in vivo evaluation. The proposed chromatographic methods are simple, rapid and accurate for the determination of amlodipine in pharmaceutical dosage forms and can be used for routine quality control of drugs and in vitro dissolution study.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1815
Author(s):  
Aboli Girme ◽  
Sandeep Pawar ◽  
Chetana Ghule ◽  
Sushant Shengule ◽  
Ganesh Saste ◽  
...  

Kashmir saffron (Crocus sativus L.), also known as Indian saffron, is an important Asian medicinal plant with protective therapeutic applications in brain health. The main bioactive in Kashmir or Indian Saffron (KCS) and its extract (CSE) are apocarotenoids picrocrocin (PIC) and safranal (SAF) with carotenoids, crocetin esters (crocins), and crocetins. The ultra-fast liquid chromatography(UFLC)- photodiode array standardization confirmed the presence of biomarkers PIC, trans-4-GG-crocin (T4C), trans-3-Gg-crocin (T3C), cis-4-GG-crocin (C4C), trans-2-gg-crocin (T2C), trans-crocetin (TCT), and SAF in CSE. This study’s objectives were to develop and validate a sensitive and rapid UFLC-tandem mass spectrometry method for PIC and SAF along T4C and TCT in rat plasma with internal standards (IS). The calibration curves were linear (R2 > 0.990), with the lower limit of quantification (LLOQ) as 10 ng/mL. The UFLC-MS/MS assay-based precision (RSD, <15%) and accuracy (RE, −11.03–9.96) on analytical quality control (QC) levels were well within the acceptance criteria with excellent recoveries (91.18–106.86%) in plasma samples. The method was applied to investigate the in vivo pharmacokinetic parameters after oral administration of 40 mg/kg CSE in the rats (n = 6). The active metabolite TCT and T4C, PIC, SAF were quantified for the first time with T3C, C4C, T2C by this validated bioanalytical method, which will be useful for preclinical/clinical trials of CSE as a potential neuroprotective dietary supplement.


1997 ◽  
Vol 77 (04) ◽  
pp. 660-667 ◽  
Author(s):  
G C White ◽  
S Courter ◽  
G L Bray ◽  
M Lee ◽  
E D Gomperts ◽  
...  

SummaryA prospective, open-label multicenter investigation has been conducted to compare pharmacokinetic parameters of recombinant DNA-derived FVIII (rFVIII) and plasma-derived FVIII concentrate (pdFVIII) and to assess safety and efficacy of long-term home-treat- ment with rFVIII for subjects with hemophilia A. Following comparative in vivo pharmacokinetic studies, 69 patients with severe (n = 67) or moderate (n = 2) hemophilia A commenced a program of home treatment using rFVIII exclusively for prophylaxis and treatment of all bleeding episodes for a period of 1.0 to 5.7 years (median 3.7 years). The mean in vivo half-lives of rFVIII and pdFVIII were both 14.7 h. In vivo incremental recoveries at baseline were 2.40%/IU/kg and 2.47%/IU/kg, respectively (p = 0.59). The response to home treatment with rFVIII was categorized as good or excellent in 3,195 (91.2%) of 3,481 evaluated bleeding episodes. Thirteen patients received rFVIII for prophylaxis for twenty-four surgical procedures. In all cases, hemostasis was excellent. Adverse reactions were observed in only 13 of 13,591 (0.096%) infusions of rFVIII; none was serious. No patient developed an inhibitor to r FVIII.


Author(s):  
Kishan Veerabrahma ◽  
Swapna Madishetty ◽  
Muzammil Afzal Syed ◽  
Prabhakar Kandadi

Cationic nanoemulsions were reported to have increased bioavailability. The aim of present study was to prepare a cationic lipid nanoemulsion of diclofenac acid (LNEs) for improved oral bioavailability to treat arthritic conditions. The LNEs of diclofenac acid were prepared by using soya bean oil, egg lecithin, cholesterol and stearylamine. Stearylamine was used as positive charge inducer. The LNEs were processed by homogenization and ultrasonication. The formulation composition was selected based on earlier reports. The LNEs were characterized for size and zeta potential. The physical stability of LNEs was studied using autoclaving, centrifugal, desorption (dilution effect) stresses and on storage. The total drug content and entrapment efficiency were determined using HPLC. During in vivo studies in Wistar rats, the pharmacokinetic parameters of LNEs were compared with a prepared diclofenac suspension in sodium CMC mucilage. The selected formulations, F1, F2 and F3, were relatively stable during centrifugal stress, dilution stress and on storage. The drug content was found to be 2.38 ± 1.70 mg/ml for F1, 2.30 ± 0.82 mg/ml for F2, and 2.45 ± 0.66 mg/ml for F3. The entrapment efficiencies were 97.83 ± 0.53%, 97.87 ± 1.22% and 98.25 ± 0.21% for F1, F2 and F3 respectively. The cumulative percentage drug release from F1, F2 and F3 showed more release in pH 6.8 phosphate buffer than in pH 1.2 HCl. During oral bioavailability studies, the LNEs showed higher serum concentrations than a suspension. The relative bioavailability of the LNE formulations F1, F2 and F3 were found to be 2.35, 2.94 and 6.28 times that of F4 suspension and were statistically significant. Of all, the cationic lipid nanoemulsion (F3) was superior in improving bioavailability, when compared with plain emulsion (F1) and cholesterol containing LNE (F2). The study helps in designing the cationic oral nanoemulsions to improve the oral bioavailability of diclofenac.


2021 ◽  
Vol 33 (7) ◽  
pp. 1692-1698
Author(s):  
S.S. Jadiya ◽  
N. Upmanyu ◽  
S. Arulmozhi ◽  
V. Jain ◽  
S. Sankaran ◽  
...  

In present study, an advanced, simple and a rapid reverse phase high performance liquid chromatography (RP-HPLC) method was developed for the quantitative determination of sulfasalazine in rabbit plasma. Sulfasalazine was separated using Chromatopak C-18 basic peerless (250 mm × 4.6 mm, 5μ) column in an isocratic mode using mobile phase consisting of the mixture of 10mM Ammonium acetate pH adjusted to 4.5 and acetonitrile (70:30 v/v) with a flow rate of about 1.0 mL/min at ambient temperature. An ultra-violet detection of sulfasalazine and the internal standard was carried out at 362 nm. Both sulfasalazine and internal standard (IS, 4-hydroxy benzoate) were extracted from plasma matrices with high efficiency using a simple protein precipitation method. The method was found to be highly selective with no carryover effects. Linearity of sulfasalazine was found with the range of 2.5-100 μg/mL with the value of r2 > 0.995 a correlation coefficient. At all three quality control levels, developed bioanalytical method was found as repeatable and reproducible as well. The average recoveries of sulfasalazine from plasma were in the range of 95.59-97.16%. The bioanalytical samples showed good and acceptable stability of sulfasalazine solution at different storage, packaging and handling conditions. Hence, in conclusion, the validated and developed HPLC-UV method could be effectively utilized for determination of sulfasalazine in pharmacokinetic studies involving novel formulations.


2021 ◽  
Vol 62 (2) ◽  
pp. 144-162
Author(s):  
Mounika Chidurala ◽  
Raveendra Reddy J

Introduction: The drawbacks assosiated with oral administration of drugscan be controlled or minimized by gastro retentive formulations that remain buoyant within the stomach for an extended time by providing prolonged gastric retention and releasethe drug in an exceedingly extended manner thereby improving bioavailability. The current research was to develop and optimize Domperidone and Famotidine floating tablets with extended release by Quality by Design approach. Method: Based on QTPP (Quality Target Product Profile), CQAs (Critical Quality Attributes)wereidentified. Risk analysis by the evaluation of formulation and process parameters showed that optimizing the levels of polymers could reduce high risk to achieve the target profile. A 23factor experimental design with midpoints was selected for statistical analysis and optimization. Results: HPMC K100 and Carbopol 934P had a positive effect while ethyl cellulose demonstrated a negative effect on the selected responses. Drug release kinetics followed the first-order release with Higuchi diffusion and Fickian diffusion. Optimized formula satisfying all the required parameters was selected and evaluated. The predicted response values were in close agreement with experimental response values. Abdominal X-ray imaging after oral administration of the tablets on a healthy rabbit’s stomach confirmed the extended floating behavior with shorter lag time. In vivo, pharmacokinetic studies in rabbits revealed that the optimized formulation exhibited prolonged drug release with enhanced Cmax, tmax, AUCo-t, and t1/2 of an optimized product when compared to the marketed product. Conclusions: It has been concluded that the application of Quality by Design in the formulation and optimization reduced the number of trials to produce a cost-effective formula.


2018 ◽  
Vol 33 (2) ◽  
pp. 65-73 ◽  
Author(s):  
Dmitriy V. Ivashchenko ◽  
Anastasia V. Rudik ◽  
Andrey A. Poloznikov ◽  
Sergey V. Nikulin ◽  
Valeriy V. Smirnov ◽  
...  

Abstract Background: Phenazepam (bromdihydrochlorphenylbenzodiazepine) is the original Russian benzodiazepine tranquilizer belonging to 1,4-benzodiazepines. There is still limited knowledge about phenazepam’s metabolic liver pathways and other pharmacokinetic features. Methods: To determine phenazepam’s metabolic pathways, the study was divided into three stages: in silico modeling, in vitro experiment (cell culture study), and in vivo confirmation. In silico modeling was performed on the specialized software PASS and GUSAR to evaluate phenazepam molecule affinity to different cytochromes. The in vitro study was performed using a hepatocytes’ cell culture, cultivated in a microbioreactor to produce cytochrome P450 isoenzymes. The culture medium contained specific cytochrome P450 isoforms inhibitors and substrates (for CYP2C9, CYP3A4, CYP2C19, and CYP2B6) to determine the cytochrome that was responsible for phenazepam’s metabolism. We also measured CYP3A activity using the 6-betahydroxycortisol/cortisol ratio in patients. Results: According to in silico and in vitro analysis results, the most probable metabolizer of phenazepam is CYP3A4. By the in vivo study results, CYP3A activity decreased sufficiently (from 3.8 [95% CI: 2.94–4.65] to 2.79 [95% CI: 2.02–3.55], p=0.017) between the start and finish of treatment in patients who were prescribed just phenazepam. Conclusions: Experimental in silico and in vivo studies confirmed that the original Russian benzodiazepine phenazepam was the substrate of CYP3A4 isoenzyme.


Sign in / Sign up

Export Citation Format

Share Document