Formulation Optimization and Evaluation of Nanostructured Lipid Carriers Containing Valsartan

Author(s):  
Ravish J Patel ◽  
Zil P Patel

Nanostructured lipid carriers (NLCs), a lipid based colloidal carrier system, offer many advantages such as increase the solubility, improves the bioavailability and therapeutic efficacy. Incorporation of liquid lipid can improve the drug loading capacity in the NLCs. Valsartan is an antihypertensive drug with low oral bioavailability ranging from 10-35% because of poor solubility and extensive first pass hepatic metabolism. The purpose of present study was to develop and characterize the valsartan loaded nanostructured lipid carriers (Val-NLCs) to enhance the solubility, bypass the hepatic first-pass metabolism, and enhance the lymphatic absorption leading to greater oral bioavailability. Valsartan loaded NLCs were prepared by melt emulsification method and optimized using a two level full factorial design. Effect of content of Capmul MCM EP on crystallinity of tristearin was studied by differential scanning calorimetry (DSC) method. The particle size, entrapment efficiency, drug loading and zeta potential values of optimized batch were 62±0.494 nm, 86.59±0.671, 8.65±0.06 % and -17.4 mV, respectively. TEM images showed spherical particles with diameter of around 50 nm. In vitro drug release of 70% was observed at the end of 12 hrs. Ex-vivo drug release of 90% was observed in 2 hrs. Stability study indicated that the prepared Val-NLCs suspension was stable at refrigerator conditions for one month. Lyophilization produced free flowing Val-NLCs powder from suspension and was easy to reconstitute. Based on these results, it is concluded that NLCs are promising drug delivery for improving the oral bioavailability of valsartan.

Author(s):  
Pierre A. Hanna ◽  
Mamdouh M. Ghorab ◽  
Shadeed Gad

Introduction: Betamethasone dipropionate is a highly effective corticosteroid anti-inflammatory. However, the main drawback of its topical use is the limited skin penetration into deeper skin layers. Also, its systemic use has shown many side effects. </P><P> Objective: The goal of this research was to formulate betamethasone dipropionate in nanostructured lipid carriers (NLC) formulae that contain oleic acid to aid its penetration to deeper skin layers and to aid absorption to local regions upon topical application. </P><P> Methods: NLC formulae were prepared by high shear homogenization then sonication. Formulae were characterized for their particle size, size distribution, electric potential, occlusion factor, entrapment efficiency, drug loading, transmission electron microscopy, in vitro drug release, and ex vivo skin penetration. Compatibility of ingredients with drug was tested using differential scanning calorimetry. Formulae were shown to have appropriate characteristics. NLC formulae were superior to traditional topical formulation in drug release. </P><P> Results: Upon testing ex vivo skin penetration, betamethasone dipropionate prepared in NLC formulae was shown to penetrate more efficiently into skin layers than when formulated as a traditional cream. NLC formulation that contained higher percentage of oleic acid showed higher penetration and higher amount of drug to pass through skin. </P><P> Conclusion: In general, NLC with lower oleic acid percentage was shown to deliver betamethasone dipropionate more efficiently into deeper skin layers while that of a higher oleic acid percentage was shown to deliver the drug more efficiently into deeper skin layers and through the skin, transdermally.


Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1085 ◽  
Author(s):  
Aditya Murthy ◽  
Punna Rao Ravi ◽  
Himanshu Kathuria ◽  
Shrinivas Malekar

Raloxifene hydrochloride (RLX) shows poor bioavailability (<2%), high inter-patient variability and extensive gut metabolism (>90%). The objective of this study was to develop nanostructured lipid carriers (NLCs) for RLX to enhance its bioavailability. The NLC formulations were produced with glyceryl tribehenate and oleic acid. The particle characteristics, entrapment efficiency (EE), differential scanning calorimetry (DSC), in vitro drug release, oral bioavailability (in rats) and stability studies were performed. The optimized nanoparticles were 120 ± 3 nm in size with positive zeta potential (14.4 ± 0.5 mV); % EE was over 90% with the drug loading of 5%. The RLX exists in an amorphous form in the lipid matrix. The optimized RLX-NLC formulation showed sustained release in vitro. The RLX-NLC significantly (p < 0.05) enhanced oral bioavailability 3.19-fold as compared to RLX-free suspension in female Wistar rats. The RLX-NLC can potentially enhance the oral bioavailability of RLX. It can also improve the storage stability.


2020 ◽  
Vol 17 (3) ◽  
pp. 246-256
Author(s):  
Kriti Soni ◽  
Ali Mujtaba ◽  
Md. Habban Akhter ◽  
Kanchan Kohli

Aim: The intention of this investigation was to develop Pemetrexed Diacid (PTX)-loaded gelatine-cloisite 30B (MMT) nanocomposite for the potential oral delivery of PTX and the in vitro, and ex vivo assessment. Background: Gelatin/Cloisite 30 B (MMT) nanocomposites were prepared by blending gelatin with MMT in aqueous solution. Methods: PTX was incorporated into the nanocomposite preparation. The nanocomposites were investigated by Fourier Transmission Infra Red Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Scanning Electron Microscope (SEM) X-Ray Diffraction (XRD) and Confocal Laser Microscopy (CLSM). FT-IR of nanocomposite showed the disappearance of all major peaks which corroborated the formation of nanocomposites. The nanocomposites were found to have a particle size of 121.9 ± 1.85 nm and zeta potential -12.1 ± 0.63 mV. DSC thermogram of drug loaded nanocomposites indicated peak at 117.165 oC and 205.816 oC, which clearly revealed that the drug has been incorporated into the nanocomposite because of cross-linking of cloisite 30 B and gelatin in the presence of glutaraldehyde. Results: SEM images of gelatin show a network like structure which disappears in the nanocomposite. The kinetics of the drug release was studied in order to ascertain the type of release mechanism. The drug release from nanocomposites was in a controlled manner, followed by first-order kinetics and the drug release mechanism was found to be of Fickian type. Conclusion: Ex vivo gut permeation studies revealed 4 times enhancement in the permeation of drug present in the nanocomposite as compared to plain drug solution and were further affirmed by CLSM. Thus, gelatin/(MMT) nanocomposite could be promising for the oral delivery of PTX in cancer therapy and future prospects for the industrial pharmacy.


2012 ◽  
Vol 62 (4) ◽  
pp. 529-545 ◽  
Author(s):  
Anuj Chawla ◽  
Pooja Sharma ◽  
Pravin Pawar

The aim of the study was to prepare site specific drug delivery of naproxen sodium using sodium alginate and Eudragit S-100 as a mucoadhesive and pH-sensitive polymer, respectively. Core microspheres of alginate were prepared by a modified emulsification method followed by cross-linking with CaCl2, which was further coated with the pH dependent polymer Eudragit S-100 (2.5 or 5 %) to prevent drug release in the upper gastrointestinal environment. Microspheres were characterized by FT-IR spectroscopy, X-ray diffraction, differential scanning calorimetry and evaluated by scanning electron microscopy, particle size analysis, drug loading efficiency, in vitro mucoadhesive time study and in vitro drug release study in different simulated gastric fluids. Stability studies of the optimized formulation were carried out for 6 months. SEM images revealed that the surface morphology was rough and smooth for core and coated microspheres, respectively. Core microspheres showed better mucoadhesion compared to coated microspheres when applied to the mucosal surface of freshly excised goat colon. The optimized batch of core microspheres and coated microspheres exhibited 98.42 ± 0.96 and 95.58 ± 0.74 % drug release, respectively. Drug release from all sodium alginate microsphere formulations followed Higuchi kinetics. Moreover, drug release from Eudragit S-100 coated microspheres followed the Korsmeyer-Peppas equation with a Fickian kinetics mechanism. Stability study suggested that the degradation rate constant of microspheres was minimal, indicating 2 years shelf life of the formulation.


2019 ◽  
Vol 11 (11) ◽  
pp. 1522-1530
Author(s):  
Mahwish Kamran ◽  
Mir Azam Khan ◽  
Muhammad Shafique ◽  
Maqsood ur Rehman ◽  
Waqar Ahmed ◽  
...  

Atorvastatin is an extensively used lipid lowering agent. But the vital issue associated with it is low oral bioavailability (12%) owing to poor aqueous solubility. To overcome this tribulation, binary solid lipid nano suspension of Atorvastatin (ATO) was formulated by solvent diffusion method. The combination of stearic acid and oleic acid was utilized as a lipid carrier with Tween-80 (surfactant) along with Polyvinylpyrrolidone (co-surfactant). Optimized nano formulation was prepared by changing the formulation variables. Optimized nano suspension (ATO-4) represented particle size 228.3 ± 2.1 nm and polydispersity index (PDI) 0.225 ± 0.02 with zeta potential (ZP) – 33.6 ± 0.02 mV. Encapsulation efficiency along with drug loading capacity was 88.3 ± 2.5% and 4.9 ± 0.14% respectively. Scanning electron microscopic (SEM) analysis exposed spherical shaped amorphous particles. Differential scanning calorimetry (DSC) as well as X-ray powder diffraction (P-XRD) established reduction in drug's crystalline state. Fourier transform infrared (FTIR) spectroscopy exposed no interaction amongst the drug and formulation contents. In-vitro studies revealed sustained pattern of drug release. Stability studies confirmed refrigerated temperature as most suitable for storage of binary solid lipid nano suspension. Plasma concentration versus time curve ascertained 2.78-fold increase in oral bioavailability of ATO nano suspension compared to the marketed product (Lipitor®). Findings proposed desired improvement in oral bioavailability of ATO nano suspension with sustained drug release profile. Thus, binary solid lipid nano suspension could be utilized as an advanced drug delivery system for oral deliverance of hydrophobic drugs.


Author(s):  
Pooja Shettigar ◽  
Marina Koland ◽  
S. M. Sindhoor ◽  
Ananth Prabhu

Background: Clarithromycin is a macrolide antibiotic used in acne treatment, but it has poor solubility, which decreases its permeability through lipid barriers such as skin. Nanostructured lipid carriers can enhance the permeability of clarithromycin through the skin, thus improving its potential for controlling acne. Aim: To formulate and evaluate Nanostructured lipid carriers of clarithromycin for topical delivery in acne treatment Methods: Nanostructured lipid carriers were prepared by emulsification and ultrasonication methods using lipids such as glycerol monostearate and oleic with poloxamer 188 as stabilizer. These nano-carriers were optimized with the help of the Quality by Design (QbD) approach employing Design-Expert® software. The nanoparticles were characterized for particle size analysis, zeta potential, drug-excipient compatibility, entrapment efficiency, and surface morphology by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The nano-carriers were also investigated for in vitro drug release and ex vivo permeation through excised goat skin. The optimized formulation was incorporated into topical carbopol gel base, formulated and examined for pH, viscosity, spreadability, in vitro drug release, ex vivo permeation, and stability under accelerated conditions. Results: The average particle size of the optimized nanoparticles was 164.8 nm, and zeta potential was -39.2 mV. FTIR studies showed that drug and lipids are compatible with each other. The morphology study by SEM and TEM showed spherical shaped particles. The entrapment efficiency of the optimized formulation was found to be 88.16%. In vitro drug release studies indicated sustained release from the formulation due to diffusion through the lipid matrix of the particles. The ex vivo permeation study using goat skin produced greater permeation from the NLC gel (89.5%) than marketed gel (65%) due to the lipid solubility of the nanoparticles in the skin. The formulation was stable under accelerated conditions. Conclusion: The optimized formulation can be considered as promising nano-carriers suitable for the sustained release of clarithromycin into the skin for effective control of acne.


2019 ◽  
Vol 16 (3) ◽  
pp. 242-253 ◽  
Author(s):  
Kaleem Ullah ◽  
Muhammad Sohail ◽  
Abdul Mannan ◽  
Haroon Rashid ◽  
Aamna Shah ◽  
...  

Objective: The study describes the development of chitosan-based (AMPS-co-AA) semi-IPN hydrogels using free radical polymerization technique. Methods: The resulting hydrogels were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), X-Ray diffraction (XRD), and Scanning Electron Microscopy (SEM). The successful crosslinking of chitosan, 2- Acrylamido-2-Methylpropane Sulfonic Acid (AMPS), and Acrylic Acid (AA) was confirmed by FT IR. Unloaded and drug-loaded hydrogels exhibited higher thermal stability after crosslinking compared to the individual components. XRD confirmed the decrease in crystallinity after hydrogel formation and molecular dispersion of Oxaliplatin (OXP) in the polymeric network. SEM showed rough, vague and nebulous surface resulting from crosslinking and loading of OXP. Results: The experimental results revealed that swelling and drug release were influenced by the pH of the medium being low at acidic pH and higher at basic pH. Increasing the concentration of chitosan and AA enhanced the swelling, drug loading and drug release while AMPS was found to act inversely. Conclusion: It was confirmed that the hydrogels were degraded more by specific enzyme lysozyme as compared to the non-specific enzyme collagenase. In-vitro cytotoxicity suggested that the unloaded hydrogels were non-cytotoxic while crude drug and drug-loaded hydrogel exhibited dose-dependent cytotoxicity against HCT-116 and MCF-7. Results of acute oral toxicity on rabbits demonstrated that the hydrogels are non-toxic up to 3900 mg/kg after oral administration, as no toxicity or histopathological changes were observed in comparison to control rabbits. These pH-sensitive hydrogels appear to provide an ideal basis as a safe carrier for oral drug delivery.


Author(s):  
Himabindu Peddapalli ◽  
Vasudha Bakshi ◽  
Narender Boggula

Objective: Olmesartan belongs to a class of angiotensin II receptor blockers. It is used in the treatment of hypertension. However, it undergoes extensive hepatic first-pass metabolism, resulting in low oral bioavailability is about 26%. The aim of this study was to prepare and evaluate the mucoadhesive buccal tablets of olmesartan with a goal to increase the bioavailability and improve the patient compliance.Methods: Mucoadhesive buccal tablets were prepared by a direct compression technique using mucoadhesive polymers such as hydroxypropyl methylcellulose (HPMC K4M), sodium carboxymethylcellulose (SCMC), and Carbopol 934P. The tablets were evaluated for weight variation, thickness, hardness, friability, surface pH, swelling index, drug content uniformity, in vitro drug release, ex vivo mucoadhesive strength, ex vivo mucoadhesive time, and ex vivo permeation studies. The release kinetics was calculated to determine the drug release mechanism. Results: The physicochemical properties of all the formulations were shown to be within the limits. The optimized buccal tablets F2, F7, and F11 showed satisfactory drug release rates with the diffusion controlled mechanism. Optimized buccal tablets developed for olmesartan possess reasonable mucoadhesive strength, mucoadhesive time, and surface pH was in an acceptable salivary pH 6.76±0.28–6.89±0.34. The ex vivo permeation studies for optimized tablets were shown satisfactory drug permeation and could meet the target flux 0.991 mg h−1cm−2.Conclusion: The obtained results could be used as a platform to develop the buccal delivery of this drug, which bypasses the first-pass metabolism and results in the improvement of bioavailability. Hence, the present study concludes that the olmesartan could be delivered through the buccal route.


Author(s):  
Banasmita Kalita ◽  
Kritika Saikia ◽  
Bhupen Kalita

ABSTRACTObjectives: The objective of the present work is to develop and characterize metronidazole microsphere-loaded bioadhesive vaginal gel to ensurelonger residence time at the infection site, providing a favorable release profile for the drug.Methods: Microsphere was prepared by solvent evaporation method in various ratios of metronidazole to poly-ε-caprolactone (PCL). Physicochemicalevaluation of microspheres includes determination of solubility in simulated vaginal fluid, partition coefficient (n-octanol/citrate phosphatebuffer pH 4.5), particle size distribution, entrapment efficiency, X-ray diffraction, and surface morphology by scanning electron microscopy (SEM).Drug excipient compatibility was established by Fourier transform infrared and differential scanning calorimetry studies. Bioadhesive gel wasprepared using Carbopol 934P and HPMC K4M in various concentrations, and methyl paraben was used as a preservative. The pH was adjustedwith triethanolamine which resulted in a translucent gel. The optimized metronidazole microsphere formulation was dispersed into the gel base.Microspheres in gel formulations were evaluated for pH, viscosity, spreadability, drug content, and gelling strength. Ex vivo mucoadhesive strength ofthe gel was determined on goat vaginal mucosa. In vitro drug release study was performed using cellophane membrane.Results: The optimized batch of microsphere F4 (drug-polymer ratio 1:4) showed entrapment efficiency of 72.62±3.66%, solubility of 1.5 mg/ml, andpartition coefficient of 0.12. Particle size of all the formulations was observed below 100 μm. Regular and spherical particles were observed in theSEM photomicrographs. The optimized gel formulation G5 (Carbopol and HPMC at 1: 0.25 ratio) showed viscosity of 7538 cps at 100 RPM, gel strengthrecorded as 35 secobds for a 1000.00 mg load, and spreadability of 4.6 g.cm/seconds. G5 showed 82.4% drug release at 10.0 hrs and mucoadhesivestrength of 6.5±1.2 g.Conclusion: The study results suggest that metronidazole-loaded PCL microsphere in mucoadhesive gel would provide a mean for sustainedtreatment of vaginal infections.Keywords: Microsphere, Metronidazole, Bioadhesive vaginal gel.


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