scholarly journals Microsponges for controlled release and enhanced oral bioavailability of carbamazepine

Author(s):  
Karam F. Abdalla ◽  
Mohamed A. Osman ◽  
Ahmed T. Nouh ◽  
Gamal M. El Maghraby

Abstract The oral absorption and hence the oral bioavailability of carbamazepine (CBZ) is variable even after administration of rapidly dissolving formulation. This problem was attributed to supersaturation of CBZ and transformation to the less soluble carbamazepine dihydrate (CBD). Accordingly, formulation of sustained release products of CBZ is a promising approach to overcome this problem. Microsponges is an emerging formulation which can help in this direction. The aim of this work was to optimize the composition of microsponges for better encapsulation and sustained release of CBZ for oral administration. CBZ microsponges were prepared using quasi emulsion solvent diffusion technique with varying composition of ethyl cellulose and polyvinyl alcohol (PVA). Microsponges were evaluated using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction. Production yield, entrapment efficiency and surface morphology of microsponges were assessed in addition to drug release. Optimum formulation was administered orally to albino rabbits to evaluate the oral bioavailability with reference to unprocessed CBZ. The Instrumental analysis reflected the encapsulation of CBZ in amorphous or molecularly dispersed form in the microsponges. The size and entrapment efficiency of the microsponges increased with increasing polymer contents. This was associated with reduction in CBZ release. Optimum formulation enhanced the oral absorption of CBZ. This was manifested by 2.6-fold increase in the area under the plasma concentration versus time curve compared to that of unprocessed CBZ. The study introduced microsponges as promising carriers for sustained oral delivery of CBZ.

Author(s):  
H. C. KIRAN ◽  
DHANDAPANI NAGASAMY VENKATESH ◽  
RAMAN RAJESHKUMAR

Objective: The main aim of the present investigation was to formulate and evaluate microbeads of zaltoprofen. Zaltoprofen, a BCS class II drug used in the treatment of rheumatoid arthritis. Zaltoprofen has a shorter half-life of 2.8 h, and it is administered at a dose of 80 mg thrice a day. By encapsulating the drug into microbeads, it is expected that the release of the drug would be prolonged and thereby, it reduces the frequency of administration and better patient compliance may be improved. Methods: Gellan-chitosan and calcium chloride beads of zaltoprofen were prepared employing ionotropic gelation method using different concentrations of gellan, chitosan, calcium chloride and zaltoprofen. The microbeads were evaluated for its various Physico-chemical parameters such as particle size determination, drug entrapment efficiency, infrared spectroscopy study, differential scanning calorimetry, X-ray diffraction analysis, scanning electron microscopy, in vitro drug release study and in vivo oral bioavailability studies. Results: The results suggested that the batch FG-II exhibited higher drug entrapment efficiency (72.42±0.013), a sustained drug release for a period of 24 h. The pharmacokinetic profile of the drug from microbeads exhibited an enhanced oral bioavailability (2.4 times higher than that of pure drug), lower elimination rate (1.14 times lesser for the drug in microbeads) with prolonged elimination half-life (2.561 times higher than pure zaltoprofen). Conclusion: Zaltoprofen entrapped microbeads demonstrated as a better delivery system for the sustained release of drug and also to circumvent the drawbacks associated with conventional therapy.


Author(s):  
Venu Madhav K ◽  
Somnath De ◽  
Chandra Shekar Bonagiri ◽  
Sridhar Babu Gummadi

Fenofibrate (FN) is used in the treatment of hypercholesterolemia. It shows poor dissolution and poor oral bioavailability after oral administration due to high liphophilicity and low aqueous solubility. Hence, solid dispersions (SDs) of FN (FN-SDs) were develop that might enhance the dissolution and subsequently oral bioavailability. FN-SDs were prepared by solvent casting method using different carriers (PEG 4000, PEG 6000, β cyclodextrin and HP β cyclodextrin) in different proportions (0.25%, 0.5%, 0.75% and 1% w/v). FN-SDs were evaluated solubility, assay and in vitro release studies for the optimization of SD formulation. Differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) analysis was performed for crystalline and morphology analysis, respectively. Further, optimized FN-SD formulation evaluated for pharmacokinetic performance in Wistar rats, in vivo in comparison with FN suspension.  From the results, FN-SD3 and FN-SD6 have showed 102.9 ±1.3% and 105.5±3.1% drug release, respectively in 2 h. DSC and PXRD studies revealed that conversion of crystalline to amorphous nature of FN from FT-SD formulation. SEM studies revealed the change in the orientation of FN when incorporated in SDs. The oral bioavailability FN-SD3 and FN-SD6 formulations exhibited 2.5-folds and 3.1-folds improvement when compared to FN suspension as control. Overall, SD of FN could be considered as an alternative dosage form for the enhancement of oral delivery of poorly water-soluble FN.


Author(s):  
Arundhati Bhattacharyya ◽  
M Bajpai

Ketoconazole is an imidazole antifungal drug belonging to the class II of Biopharmaceutic Classification System. Maintenance of gastric acidity is essential for adequate dissolution and absorption of ketoconazole. Concurrent administration of antacid and antiulcer preparations decreases the oral absorption of ketoconazole often causing therapeutic failure.  The aim of this study was to evaluate whether a self-emulsifying formulation of ketoconazole would be able to overcome the pH dependent dissolution and oral bioavailability. Self-emulsifying drug delivery system (SEDDS) was prepared after selecting the oil, surfactant and co-surfactant by solubility analysis. Optimum ratio of the components was finalized on the basis of drug content, self-emulsification and mean droplet diameter. The effect of pH on dissolution was studied in comparison to the pure drug. Oral bioavailability was determined in comparison to aqueous suspension in rats and the effect of co-administration of ranitidine hydrochloride solution and a commercially available liquid antacid preparation was studied. The optimized formulation containing 20% Capryol 90 and 40% each of Carbitol and Tween 80, exhibited 100% drug release regardless of the pH whereas the pure drug exhibited a highly pH dependent dissolution. The AUC0-24 resulted with oral administration of the SEDDS formulation was about 34%, 43% and 60% higher compared to the aqueous suspension when administered alone, administered with ranitidine and administered with antacid respectively. The results of the present study demonstrate that self-emulsifying formulations can be utilized for oral delivery of weakly basic drugs like ketoconazole which exhibit pH dependent dissolution.


Author(s):  
Kumara Swamy S ◽  
Ramesh Alli

The purpose of this study was to develop and evaluate irbesartan (IS) loaded solid lipid nanoparticles (SLNs; IS-SLNs) that might enhance the oral bioavailability of IS. IS, an angiotensin-receptor antagonist, used to treat hypertension. However, poor aqueous solubility and poor oral bioavailability has limited therapeutic applications of IS. Components of the SLNs include either of trimyristin/tripalmitin/tristearin/trilaurate/stearic acid/beeswax, and surfactants (Poloxamer 188 and soylecithin). The IS-SLNs were prepared by hot homogenization followed by ultrasonication method and evaluated for particle size, poly dispersity index (PDI), zeta potential (ZP), entrapment efficiency (EE), drug content and in vitro drug release. The physical stability of optimized formulation was studied at refrigerated and room temperature for two months. The optimized IS-SLN formulation (F4) had a mean diameter of about 217.6±3.62 nm, PDI of 0.163±0.032, ZP of -28.5±4.12, assay of 99.8±0.51 and EE of 93.68±2.47%. The formulation showed sustained drug release compared with control formulation over 24 h. Optimized formulation was found to be stable over two months. IS-SLN showed nearly spherical in shape using and converted to amorphous form by DSC. Thus, the results conclusively demonstrated SLNs could be considered as an alternative delivery system for the oral bioavailability enhancement of IS.


Pharmaceutics ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 135 ◽  
Author(s):  
Seung Han ◽  
Qili Lu ◽  
Kyeong Lee ◽  
Young Choi

P-glycoprotein (P-gp)-mediated efflux of docetaxel in the gastrointestinal tract mainly impedes its oral chemotherapy. Recently, LC478, a novel di-substituted adamantyl derivative, was identified as a non-cytotoxic P-gp inhibitor in vitro. Here, we assessed whether LC478 enhances the oral bioavailability of docetaxel in vitro and in vivo. LC478 inhibited P-gp mediated efflux of docetaxel in Caco-2 cells. In addition, 100 mg/kg of LC478 increased intestinal absorption of docetaxel, which led to an increase in area under plasma concentration-time curve (AUC) and absolute bioavailability of docetaxel in rats. According to U.S. FDA criteria (I, an inhibitor concentration in vivo tissue)/(IC50, inhibitory constant in vitro) >10 determines P-gp inhibition between in vitro and in vivo. The values 15.6–20.5, from (LC478 concentration in intestine, 9.37–12.3 μM)/(IC50 of LC478 on P-gp inhibition in Caco-2 cell, 0.601 μM) suggested that 100 mg/kg of LC478 sufficiently inhibited P-gp to enhance oral absorption of docetaxel. Moreover, LC478 inhibited P-gp mediated efflux of docetaxel in the ussing chamber studies using rat small intestines. Our study demonstrated that the feasibility of LC478 as an ideal enhancer of docetaxel bioavailability by P-gp inhibition in dose (concentration)-dependent manners.


Author(s):  
DHANDAPANI NAGASAMY VENKATESH ◽  
PREETY RAO ◽  
RAMAN RAJESHKUMAR

Objective: The main objective of the present investigation was to develop microbeads of tenofovir. Tenofovir, a BCS class III drug has a poor bioavailability of 25%, and it is administered 300 mg once a day. By incorporating the drug into a microparticulate carrier, it is expected that the dissolution profile and the oral bioavailability may be increased. Methods: Reinforced gellan-chitosan and calcium chloride beads of tenofovir were prepared by ionotropic gelation method employing various different concentrations of gellan, chitosan, calcium chloride and tenofovir. The beads were evaluated for various physico-chemical parameters such as particle size determination, drug entrapment efficiency, swelling studies, infra red spectroscopy study, differential scanning calorimetry, x-ray diffraction analysis, scanning electron microscopy, in vitro drug release study, cytotoxicity study and in vivo oral bioavailability studies. Results: From the results, it can be concluded that the formulation TB-III exhibited higher drug entrapment efficiency (46.09±0.21), a higher swelling index, sustained drug release for a period of 24 h. The pharmacokinetic profile of the drug from microbeads exhibited an increased oral bioavailability (1.25 times higher than that of pure drug), decreased elimination rate (1.32 times lesser for drug in microbeads) with prolonged elimination half-life (1.32 times higher than pure tenofovir). Conclusion: Tenofovir loaded microbeads demonstrated as a better delivery system for the modified release of drug and also to navigate the drawbacks associated with the conventional therapy.


2020 ◽  
Vol 15 (8) ◽  
pp. 1934578X2094835
Author(s):  
Chengxia Liu ◽  
Ting-ting Jiang ◽  
Zhi-xiang Yuan ◽  
Yu Lu

Triptolide (TP), a broad-spectrum antitumor drug, has very poor solubility and oral bioavailability, which limits its clinical use. Compared with conventional formulations of TP, a casein (Cas)-based drug delivery system has been reported to have significant advantages for the improvement of solubility and bioavailability of insoluble drugs. In this paper, we report the successful preparation of TP-loaded Cas nanoparticles (TP-Cas) using the self-assembly characteristics of Cas in water and the optimization of the formulation by evaluation of entrapment efficiency (EE) and loading efficiency (LE). Dynamic light scattering, transmission electron microscopy, Fourier-transform infrared spectrometry, X-ray diffractometry (XRD), and differential scanning calorimetry (DSC) was adopted to characterize the TP-Cas. Results showed that the obtained TP-Cas were approximately spherical with a particle size of 128.7 ± 11.5 nm, EE of 72.7 ± 4.7 %, and LE of 8.0% ± 0.5%. Furthermore, in vitro release behavior of TP-Cas in PBS (pH = 7.4) was also evaluated, showing a sustained-release profile. Additionally, an in vivo study in rats displayed that the mean plasma concentration of TP after oral administration of TP-Cas was significantly higher than that treated with TP oral suspension. The C max value for TP-Cas (8.0 ± 4.4 μg/mL) was significantly increased compared with the free TP (0.9 ± 0.3 μg/mL). Accordingly, the area under the curve (AUC0-8) of TP-Cas was 2.8 ± 0.8 mg/L·h, 4.3-fold higher than that of TP suspension (0.6 ± 0.1 mg/L·h). Therefore, it can be concluded that TP-Cas enhanced the absorption and improved oral bioavailability of TP. Taking the good oral safety of Cas into consideration, TP-Cas should be a more promising preparation of TP for clinical application.


Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5432
Author(s):  
Haniza Hassan ◽  
Siti Khadijah Adam ◽  
Ekram Alias ◽  
Meor Mohd Redzuan Meor Mohd Affandi ◽  
Ahmad Fuad Shamsuddin ◽  
...  

Treatment of herpes simplex infection requires high and frequent doses of oral acyclovir to attain its maximum therapeutic effect. The current therapeutic regimen of acyclovir is known to cause unwarranted dose-related adverse effects, including acute kidney injury. For this reason, a suitable delivery system for acyclovir was developed to improve the pharmacokinetic limitations and ultimately administer the drug at a lower dose and/or less frequently. In this study, solid lipid nanoparticles were designed to improve the oral bioavailability of acyclovir. The central composite design was applied to investigate the influence of the materials on the physicochemical properties of the solid lipid nanoparticles, and the optimized formulation was further characterized. Solid lipid nanoparticles formulated from Compritol 888 ATO resulted in a particle size of 108.67 ± 1.03 nm with an entrapment efficiency of 91.05 ± 0.75%. The analyses showed that the optimum combination of surfactant and solid lipid produced solid lipid nanoparticles of good quality with controlled release property and was stable at refrigerated and room temperature for at least 3 months. A five-fold increase in oral bioavailability of acyclovir-loaded solid lipid nanoparticles was observed in rats compared to commercial acyclovir suspension. This study has presented promising results that solid lipid nanoparticles could potentially be used as an oral drug delivery vehicle for acyclovir due to their excellent properties.


2016 ◽  
Vol 70 (2) ◽  
Author(s):  
Gwendolen Ong Sze Huei ◽  
Saravanan Muniyandy ◽  
Thenapakiam Sathasivam ◽  
Anand Kumar Veeramachineni ◽  
Pushpamalar Janarthanan

The formation and smooth recovery of ibuprofen encapsulated in microcapsules using gelatin and carboxymethyl cellulose (CMC) complex coacervation without glutaraldehyde were the objectives of this investigation. The microcapsules were recovered as ionically cross-linked beads using aqueous ferric chloride in 50 vol. % of 2-propanol. A physical mixture of CMC/gelatin (FP1) and CMC alone (FP2) beads was also prepared for comparison. The drug-entrapment efficiency of complex coacervate beads (FP3–FP5) was dependent on the drug-to-polymer ratio and was in the range of 86–92 mass %. Beads prepared with the highest ratio of the drug (FP5) exhibited the lowest entrapment. FP1 and FP2 beads exhibited an entrapment efficiency of 98.5 mass % and 91.3 mass %, respectively. Infrared spectroscopy (FTIR) revealed different functional groups in complex coacervate, physical mixture and FP2 beads. Optical and scanning electron microscopy revealed the distinct appearance and surface morphology of the various beads. The stable and crystalline nature of ibuprofen in the beads was confirmed by FTIR and differential scanning calorimetry (DSC), respectively. Ibuprofen release from FP1 and FP2 beads was very slow and unsuitable for oral delivery. The bead prepared by complex coacervation (FP5) showed a better release profile over 48 h and could be developed as a sustained drug delivery system.


ADMET & DMPK ◽  
2020 ◽  
Author(s):  
Tahlia R Meola ◽  
Kara Paxton ◽  
Paul Joyce ◽  
Hayley B Schultz ◽  
Clive A Prestidge

<p class="ADMETabstracttext">Lipid-based formulations (LBFs) are well-known to improve the oral bioavailability of poorly water-soluble drugs (PWSDs) by presenting the drug to the gastrointestinal environment in a molecularly dispersed state, thus avoiding the rate-limiting dissolution step. Risperidone and lurasidone are antipsychotics drugs which experience erratic and variable absorption, leading to a low oral bioavailability. The aim of this research was to develop and investigate the performance of risperidone and lurasidone when formulated as an emulsion and silica-lipid hybrid (SLH). Lurasidone and risperidone were dissolved in Capmul® MCM at 100% and 80% their equilibrium solubility, respectively, prior to forming a sub-micron emulsion. SLH microparticles were fabricated by spray-drying a silica stabilised sub-micron emulsion to form a solid powder. The performances of the formulations were evaluated in simulated intestinal media under digesting conditions, where the emulsion and SLH provided a 17-fold and 23-fold increase in LUR solubilisation, respectively. However, the performance of RIS was reduced by 2.2-fold when encapsulated within SLH compared to pure drug. Owing to its pKa, RIS adsorbed to the silica and thus, dissolution was significantly hindered. The results reveal that LBFs may not overcome the challenges of all PWSDs and physiochemical properties must be carefully considered when predicting drug performance.</p>


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