Thermosensitive Liposomes Encapsulating Anti-Cancer Agent Lomustine, and Contrast Medium Iohexol, for Thermochemotherapy: Preparation, Characterization, and In Vivo Evaluation

2020 ◽  
Vol 20 (10) ◽  
pp. 6070-6076
Author(s):  
Shuoye Yang ◽  
Wensheng Zhu ◽  
Zhenwei Wang ◽  
Yongmei Xiao ◽  
Pu Mao ◽  
...  

Thermosensitive liposome-based drug delivery systems (DDS) are powerful tools for site-specific delivery of chemotherapeutics, especially when combined with regional hyperthermia. The objective of this work was to develop a novel thermosensitive liposomal DDS loaded with lomustine, a chemotherapeutic compound, and iohexol, a contrast medium for visualization by CT. Thermosensitive compound liposomes (TSCLs) composed of DPPC were prepared by reverse-phase evaporation and investigated for encapsulation efficiency, temperature-sensitivity, release kinetics, and In Vivo pharmacokinetics. The size and zeta-potential of TSCLs ranged from 250 to 300 nm and −15 to −30 mV, respectively. At 41 °C, TSCLs were shown to release over 90% of iohexol and lomustine within 4 h. The in vitro release profiles of iohexol and lomustine at 41 °C conformed to first-order kinetics and Weibullmodel, respectively. Phase-transition did not occur after incorporation of cholesterol and soybean phospholipids. In Vivo evaluation performed with C6 glioma model rats proved the prolonged half-lives and improved bioavailability by liposomal encapsulation for both compounds under mild local hyperthermia. The TSCLs used in this study may offer a clinically promising mean of increasing efficacy and controlling toxicity.

Author(s):  
Mohini Sihare ◽  
Rajendra Chouksey

Aim: Nateglinide is a quick acting anti-diabetic medication whose potent activity lasts for a short duration. One of the dangerous side effects of nateglinide administration is rapid hypoglycemia, a condition that needs to be monitored carefully to prevent unnecessary fatalities. The aim of the study was to develop a longer lasting and slower releasing formulation of nateglinide that could be administered just once daily. Methods: Matrix tablets of nateglinide were prepared in combination with the polymers hydroxypropylmethylcellulose (HPMC), eudragits, ethyl cellulose and polyethylene oxide and the formulated drug release patterns were evaluated using in vitro and in vivo studies. Conclusion: Of the seventeen formulated matrix tablets tested, only one formulation labelled HA-2 that contained 15% HPMC K4M demonstrated release profile we had aimed for. Further, swelling studies and scanning electron microscopic analysis confirmed the drug release mechanism of HA-2. The optimized formulation HA-2 was found to be stable at accelerated storage conditions for 3 months with respect to drug content and physical appearance. Mathematical analysis of the release kinetics of HA-2 indicated a coupling of diffusion and erosion mechanisms. In-vitro release studies and pharmacokinetic in vivo studies of HA-2 in rabbits confirmed the sustained drug release profile we had aimed for. Keywords: Hydroxypropylmethylcellulose, Matrix tablets, Nateglinide, Sustained release


Author(s):  
Bhikshapathi D.V. R. N. ◽  
Ranjith Kumar K

The aim of the present investigation was to prepare and evaluate the Misoprostol mucoadhesive microspheres for gastroretentive drug delivery. Sodium alginate and sodium carboxy methyl cellulose were used as mucoadhesive polymers. Microsphere formulations were prepared using Ionotropic gelation technique. All the microspheres were characterized for particle size, scanning electron microscopy, FT-IR study, percentage yield, drug entrapment, stability studies and for in vitro release kinetics. Based on the results, the formulation M12 was selected as optimized formulation. In vitro drug release study of optimized formulation M12 showed 98.23% after 12 h in a controlled manner, which is essential for anti ulcer therapy. The marketed product shows the drug release of 95.23 within 1 h. The results of mucoadhesion study showed better retention of prepared microspheres (8) h in chic duodenal and jejunum regions of intestine. The results showed significant higher retention of mucoadhesive microspheres in upper GI tract. Pharmacokinetic study revealed that the bioavailability was found to be increased significantly when compared with marketed tablets. The drug release of Misoprostol optimized formulation M12 followed zero order, Higuchi and Korsmeyer-Peppas kinetics indicating diffusion controlled with non-Fickian (anomalous) transport thus it projected that delivered its active ingredient by coupled diffusion and erosion. Overall, the result indicated prolonged delivery with improved bioavailability of Misoprostol from mucoadhesive microspheres due to higher retention in the upper GI tract.


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.


2012 ◽  
Vol 512-515 ◽  
pp. 1821-1825
Author(s):  
Lin Zhang ◽  
Xue Min Cui ◽  
Qing Feng Zan ◽  
Li Min Dong ◽  
Chen Wang ◽  
...  

A novel microsphere scaffolds composed of chitosan and β-TCP containing vancomycin was designed and prepared. The β-TCP/chitosan composite microspheres were prepared by solid-in-water-in-oil (s/w/o) emulsion cross-linking method with or without pre-cross-linking process. The mode of vancomycin maintaining in the β-TCP/chitosan composite microspheres was detected by Fourier transform infrared spectroscopy (FTIR). The in vitro release curve of vancomycin in simulated body fluid (SBF) was estimated. The results revealed that the pre-cross-linking prepared microspheres possessed higher loading efficiency (LE) and encapsulation efficiency (EE) especially decreasing the previous burst mass of vancomycin in incipient release. These composite microspheres got excellent sphere and well surface roughness in morphology. Vancomycin was encapsulated in composite microspheres through absorption and cross-linking. While in-vitro release curves illustrated that vancomycin release depond on diffusing firstly and then on the degradation ratio later. The microspheres loading with vancomycin would be to restore bone defect, meanwhile to inhibit bacterium proliferation. These bioactive, degradable composite microspheres have potential applications in 3D tissue engineering of bone and other tissues in vitro and in vivo.


2009 ◽  
Vol 12 (1) ◽  
pp. 129 ◽  
Author(s):  
Zhihong Zhang ◽  
Bo Peng ◽  
Xinggang Yang ◽  
Chao Wang ◽  
Guangmei Sun ◽  
...  

PURPOSE. Find a novel delivery system for oral administration of drugs that have absorption window in the upper part of gastrointestinal (GI) track. METHODS. Dipyridamole was chosen as the model drug. A novel system, which combined the osmotic pump controlled release system and the floating system, was designed; matrix tablets (MT) were prepared for compares. The effects of pH, temperature and hydrodynamic conditions on drug release and the floating behavior of floating osmotic pump system (FOP) were investigated. In vivo evaluation was performed by a three-crossover study in six Beagle dogs relative to the conventional tablet (CT). Cumulative percent input in vivo was compared with that of in vitro release profiles. RESULTS. Floating behavior of FOP, drug releases from FOP and MT were sensitive to pH of dissolution media but not sensitive to temperature; the release of dipyridamole from MT was influenced by stirring rate while drug release from FOP was not. AUC of FOP was larger than MT and CT. The linear correlations between fraction absorbed in vivo and fraction dissolved in vitro was established for FOP-a true zero-order release formula, whereas only a nonlinear correlation was obtained for MT. CONCLUTIONS. FOP could be a novel way for the oral administration for drugs like dipyridamole.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1658
Author(s):  
Dalia H. Abdelkader ◽  
Ahmed Kh. Abosalha ◽  
Mohamed A. Khattab ◽  
Basmah N. Aldosari ◽  
Alanood S. Almurshedi

Atorvastatin Calcium (At-Ca) has pleiotropic effect as anti-inflammatory drug beside its main antihyperlipidemic action. Our study was conducted to modulate the anti-inflammatory effect of At-Ca to be efficiently sustained for longer time. Single oil-water emulsion solvent evaporation technique was used to fabricate At-Ca into polymeric nanoparticles (NPs). In vitro optimization survey was performed on Poly(lactide-co-glycolide) (PLGA) loaded with At-Ca regrading to particle size, polydispersity index (PDI), zeta potential, percent entrapment efficiency (% EE), surface morphology and in vitro release pattern. In vitro drug-polymers interactions were fully scanned using Fourier-Transform Infrared Spectroscopy (FTIR) and Differential Scanning calorimetry (DSC) proving that the method of fabrication is an optimal strategy maintaining the drug structure with no interaction with polymeric matrix. The optimized formula with particle size (248.2 ± 15.13 nm), PDI (0.126 ± 0.048), zeta potential (−12.41 ± 4.80 mV), % EE (87.63 ± 3.21%), initial burst (39.78 ± 6.74%) and percent cumulative release (83.63 ± 3.71%) was orally administered in Male Sprague–Dawley rats to study the sustained anti-inflammatory effect of At-Ca PLGA NPs after carrageenan induced inflammation. In vivo results demonstrate that AT-Ca NPs has a sustained effect extending for approximately three days. Additionally, the histological examination revealed that the epidermal/dermal layers restore their typical normal cellular alignment with healthy architecture.


Author(s):  
UPPULURU ASHOK KUMAR ◽  
GANDE SURESH

Objective: The present study aims at development of solid dispersions (SD) of candesartan cilexetil for enhanced solubility and bioavailability. Methods: About 18 SD formulations of candesartan cilexetil were prepared by solvent evaporation technique and evaluated. The in vitro release studies were conducted and the best formulation chosen was further characterized for Fourier transform infrared spectroscopy, Scanning electron microscope, X-ray, and stability. The in vivo evaluation study conducted in rats. Results: The formulation SD16 containing drug and Soluplus in 1:3 ratio along with 2% selective laser sintering was chosen optimal based on drug content (99.08%), and drug release (99.7%). In vivo studies conducted on SD16 showed that mean time to peak concentration (Tmax) was 2.0±0.05 and 4±0.2 h for the optimized and pure drug, respectively, while mean maximum drug concentration (Cmax) was 570.63±2.65 ng/mL and was significant as compared to the candesartan pure drug 175.146±0.07 ng/mL. Area under curve AUC0-∞ infinity for candesartan SD16 was higher (4860.61±1.05 ng.h/ml) than pure drug suspension 1480±1.72 ng.h/ml. Conclusion: Hence, the developed SD formulations enhanced the bioavailability of drug by 3 folds.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Gustavo H. Rodrigues da Silva ◽  
Gabriela Geronimo ◽  
Juan P. García-López ◽  
Lígia N. M. Ribeiro ◽  
Ludmilla D. de Moura ◽  
...  

AbstractAnesthetic failure is common in dental inflammation processes, even when modern agents, such as articaine, are used. Nanostructured lipid carriers (NLC) are systems with the potential to improve anesthetic efficacy, in which active excipients can provide desirable properties, such as anti-inflammatory. Coupling factorial design (FD) for in vitro formulation development with in vivo zebrafish tests, six different NLC formulations, composed of synthetic (cetyl palmitate/triglycerides) or natural (avocado butter/olive oil/copaiba oil) lipids were evaluated for loading articaine. The formulations selected by FD were physicochemically characterized, tested for shelf stability and in vitro release kinetics and had their in vivo effect (anti-inflammatory and anesthetic effect) screened in zebrafish. The optimized NLC formulation composed of avocado butter, copaiba oil, Tween 80 and 2% articaine showed adequate physicochemical properties (size = 217.7 ± 0.8 nm, PDI = 0.174 ± 0.004, zeta potential = − 40.2 ± 1.1 mV, %EE = 70.6 ± 1.8) and exhibited anti-inflammatory activity. The anesthetic effect on touch reaction and heart rate of zebrafish was improved to 100 and 60%, respectively, in comparison to free articaine. The combined FD/zebrafish approach was very effective to reveal the best articaine-in-NLC formulation, aiming the control of pain at inflamed tissues.


Author(s):  
Chandra Sekhar Kolli ◽  
Ramesh Gannu ◽  
Vamshi Vishnu Yamsani ◽  
Kishan V ◽  
Madhsudan Rao Yamsani

The aim of this investigation was to develop and evaluate mucoadhesive buccal patches of prochlorperazine (PCPZ). Permeation of PCPZ was calculated in vitro using porcine buccal membrane. Buccal formulations were developed by solvent-casting technique using hydroxy propylmethyl cellulose (HPMC) as mucoadhesive polymer. The patches were evaluated for in vitro release, moisture absorption and mechanical properties. The optimized formulation, based on in vitro release and moisture absorption studies, was subjected for bioadhesion studies using porcine buccal membrane. In vitro flux of PCPZ was calculated to be 2.14 ± 0.01 µg. h–1.cm–2 and buccal absorption was also demonstrated in vivo in human volunteers.             In vitro drug release and moisture absorbed was governed by HPMC content. Increasing concentration of HPMC delayed the drug release. All formulations followed Zero order release kinetics whereas the release pattern was non-Fickian. The mechanical properties, tensile strength (10.28 ± 2.27 kg mm–2 for formulation P3) and elongation at break reveal that the formulations were found to be strong but not brittle. The peak detachment force and work of adhesion for formulation P3 were 0.68 ± 0.15 N and 0.14 ± 0.08 mJ, respectively. The results indicate that suitable bioadhesive buccal patches of PCPZ with desired permeability and suitable mechanical properties could be prepared


Sign in / Sign up

Export Citation Format

Share Document