Physical stability, centrifugation tests, and entrapment efficiency studies of carnauba wax–decyl oleate nanoparticles used for the dispersion of inorganic sunscreens in aqueous media

2006 ◽  
Vol 63 (2) ◽  
pp. 115-127 ◽  
Author(s):  
J.R. Villalobos-Hernández ◽  
C.C. Müller-Goymann
Keyword(s):  
Aqueous Media ◽  
Physical Stability ◽  
Entrapment Efficiency ◽  
Carnauba Wax

Lipid-Polymer Hybrid Nanocarriers for Oral Delivery of Felodipine: Formulation, Characterization and Ex-Vivo Evaluation

2021 ◽  
Author(s):  
Hayder Kadhim Drais ◽  
Ahmed Abbas Hussein
Keyword(s):  
Oral Delivery ◽  
Ph Value ◽  
Ex Vivo ◽  
Drug Loading ◽  
Aqueous Media ◽  
Physical Stability ◽  
Entrapment Efficiency ◽  
Light Transmittance ◽  
Sustained Drug Delivery ◽  
Polymer Hybrid

Purpose: Felodipine, is a calcium-channel antagonist used for hypertension and angina pectoris. It is practically insoluble in aqueous media and shows low oral bioavailability (15%-20%). This investigation aims to prepare and characterize oral felodipine lipid-polymer hybrid nanocarriers (LPHNs) to increase solubility and control delivery for increasing bioavailability and enhance patient compliance. Methods: The newly microwave-based method was prepared with felodipine LPHNs (H1-H35) successfully. The (H1-H35) were subjected to thermodynamic stability experiments. After that, select nine felodipine LPHNs (F1-F9) that have smart physical stability for further optimization of different characterization processes. Results: The felodipine LPHNs (F4) are considered the most optimized formula. It was characterized by lower particle size (33.3 nm), lower PDI (0.314), high zeta potential (13.6 mV), entrapment efficiency is (81.645 %w/w), drug loading is (16.329 % w/w), the pH value is 4, excellent percent of light transmittance (95.5%), pseudoplastic rheogram, significantly high (p< 0.05) dissolution rate with sustained drug delivery and success ex-vivo intestinal permeation attributes. The (F4) subject for further investigations of fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The results of FTIR, AFM, and TEM indicate there is no interaction between the felodipine and excipients and that the particulate system in the nanoscale dispersion system confirms the high stability. Conclusion: The optimized felodipine LPHNs (F1-F9) formulations were smart formulations for sustained oral delivery of felodipine and that F4 was the most optimized formula according to its characterization processes.

scholarly journals PRONIOSOMES: A VESICULAR DRUG DELIVERY SYSTEM

2021 ◽  
pp. 32-36
Author(s):  
SARITHA M. ◽  
SATYA PRAKASH PANDA ◽  
SRAVANI BUDDHA ◽  
P. V. KAMALA KUMARI ◽  
Y. SRINIVASA RAO
Keyword(s):  
Drug Delivery ◽  
Aqueous Media ◽  
Physical Stability ◽  
Entrapment Efficiency ◽  
Systemic Circulation ◽  
Vital Role ◽  
Water Soluble ◽  
In Vitro Drug Release ◽  
Vesicular Carriers

In the development of new dosage forms, drug delivery using nanotechnology is playing a vital role. Vesicular drug delivery systems have gained wide attention in the field of nanotechnology, such as niosomes, liposomes and proniosomes. Among the vesicular carriers, proniosomes are superior. Proniosomes are water-soluble carrier particles that are coated with surfactant so these are dry formulations. They are rehydrated to use on agitation in hot aqueous media within minutes to form niosomal dispersion immediately. Both hydrophilic and lipophilic drugscan be incorporated into these proteasomes. The physical stability problems of niosomes like aggregation, fusion and leaking are minimized in proniosomes, routes, such as oral, parenteral, dermal and transdermal, ocular, oral mucosal, vaginal, pulmonary, and intranasal. Proniosomes prolong the existence of the drug in the systemic circulation and finally reduces toxicity. This review focuses on different aspects of proniosomes such as preparation, characterization, in vitro drug release, entrapment efficiency, applications in the present scenario in the market and future trends.

Cationic Diclofenac Lipid Nanoemulsion for Improved Oral Bioavailability: Preparation, Characterization and In Vivo Evaluation

2015 ◽  
Vol 8 (2) ◽  
pp. 2874-2880
Author(s):  
Kishan Veerabrahma ◽  
Swapna Madishetty ◽  
Muzammil Afzal Syed ◽  
Prabhakar Kandadi
Keyword(s):  
Oral Bioavailability ◽  
Physical Stability ◽  
Cationic Lipid ◽  
Entrapment Efficiency ◽  
In Vivo Studies ◽  
Pharmacokinetic Parameters ◽  
In Vivo Evaluation ◽  
Drug Content ◽  
Lipid Nanoemulsion

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.

scholarly journals Silica-Coated Magnetic Nanocomposites for Pb2+ Removal from Aqueous Solution

2020 ◽  
Vol 10 (8) ◽  
pp. 2726 ◽  
Author(s):  
Roxana Nicola ◽  
Otilia Costişor ◽  
Mihaela Ciopec ◽  
Adina Negrea ◽  
Radu Lazău ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Adsorption Capacity ◽  
Aqueous Media ◽  
Physical Stability ◽  
Absorption Capacity ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
Similar Materials ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Magnetic iron oxide-silica shell nanocomposites with different iron oxide/silica ratio were synthesized and structurally characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), small-angle neutron scattering, magnetic and N2-sorption studies. The composite that resulted with the best properties in terms of contact surface area and saturation of magnetization was selected for Pb2+ adsorption studies from aqueous media. The material presented good absorption capacity (maximum adsorption capacity 14.9 mg·g−1) comparable with similar materials presented in literature. Its chemico-physical stability and adsorption capacity recommend the nanocomposite as a cheap adsorbent material for lead.

A COMPARATIVE ASSESSMENT OF VESICULAR FORMULATIONS: TRANSFERSOMES AND CONVENTIONAL LIPOSOMES LOADED IVABRADINE HYDROCHLORIDE

2020 ◽  
pp. 51-55
Author(s):  
GITA CHAURASIA ◽  
NARENDRA LARIYA
Keyword(s):  
Drug Release ◽  
Physical Stability ◽  
Physical Appearance ◽  
Spherical Shape ◽  
Entrapment Efficiency ◽  
Tween 80 ◽  
Molar Ratio ◽  
Drug Release Study ◽  
Release Study

Objective: Ivabradine hydrochloride (IH), a benzazepine derivative used to treat cardiovascular disease angina pectoris. In this study IH-loaded novel carrier systems transfersomes (TFs) and conventional liposomes (CLs) were developed and compared for their efficacy to enhance the stability of drugs from degradation. Methods: TFs formulations (TF-1, TF-2 and TF-3) were prepared by using different biocompatible surfactants; tween-80 (TW), span-80(S) and sodium deoxycholate (SC) in the concentration ratio of 15 parts with 85 parts of soy phosphatidylcholine as phospholipid by thin-film hydration method. These vesicles were compared with CLs formulation (L-1) prepared in 7:3 molar ratio of soy phosphatidylcholine: cholesterol by following the same method. These vesicles were compared for physical appearance, vesicle shape, and size, percentage drug entrapment efficiency (%DEE), deformability index (DI), in vitro percentage cumulative drug release study, and physical stability studies. The chosen optimized novel carriers were observed under scanning electron microscopy. Results: The compared data demonstrated that the physical appearance for all vesicles was turbid and had a spherical shape. The size distribution was in the range of 129.0 nm to 273.5 nm in vesicles. The %DEE (79.0±0.94) and DI (35.0±1.9) was found maximum in TF-1 formulation that was 2.3 times higher than L-1 formulation. The in vitro percentage cumulative drug release study followed second-order polynomial kinetics that was 2.0 times higher than L-1and 2.9 times higher than the plain drug in 30 min (90.4±0.06%) from TF-1. The vesicles were found to be stable at refrigeration conditions. Conclusion: Thus, amongst of all vesicles TW loaded TFs (TF-1) was chosen as an excellent novel vesicular carrier for hydrophilic drugs due to its higher deformability behavior than CLs that protects the certain drugs from biodegradation and provides stability.

scholarly journals Entrapment of α-Amylase in Agar Beads for Biocatalysis of Macromolecular Substrate

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Manu Sharma ◽  
Vinay Sharma ◽  
Dipak K. Majumdar
Keyword(s):  
Thermal Stability ◽  
Half Life ◽  
Thermal Inactivation ◽  
Scale Up ◽  
Physical Stability ◽  
Entrapment Efficiency ◽  
Substrate Affinity ◽  
Michaelis Constant ◽  
Size Dependent ◽  
Temperature Optima

Attempts have been made to optimize immobilization parameters, catalytic property, and stability of immobilized α-amylase in agar. The work compares natural entrapment efficiency of agar with the ionotropically cross-linked agar hydrogel, with the advantage of easy scale-up and cost and time effectiveness. Beads prepared with 3% (w/v) agar and 75 mM calcium chloride and hardened for 20 minutes were selected for further studies on the basis of entrapment efficiency (80%) and physical stability. Following entrapment, pH and temperature optima of enzyme were shifted from 6 to 6.5 and 50 to 55°C, respectively. Michaelis constant (Km) for both free and entrapped enzymes remained the same (0.83%) suggesting no change in substrate affinity. However, Vmax⁡ of entrapped enzyme decreased ~37.5-fold. The midpoint of thermal inactivation for entrapped enzyme increased by 8 ± 1°C implying its higher thermal stability. The entrapped enzyme in calcium agar bead had an Ea value of 27.49 kcal/mol compared to 17.6 kcal/mol for free enzyme indicating increased stability on entrapment. Half-life of enzyme increased ~2.2 times after entrapment in calcium agar at 60°C indicating stabilization of enzyme. The reusability of beads was size dependent. Beads with diameter <710 μm were stable and could be reused for 6 cycles with ~22% loss in activity.

scholarly journals Characterization of Alginate-Cellulose-Kaolin Composites for Slow-Release Urea Fertilizer

2021 ◽  
Vol 8 (3) ◽  
pp. 219-227
Author(s):  
Sunardi Sunardi ◽  
Gusti Nia Faramitha ◽  
Uripto Trisno Santoso
Keyword(s):  
Slow Release ◽  
Aqueous Media ◽  
Entrapment Efficiency ◽  
Swelling Ratio ◽  
Release Agent ◽  
Urea Fertilizer ◽  
Wet Condition ◽  
Slow Release Urea ◽  
Cie Lab

Research on the effect of cellulose and kaolin addition to alginate-cellulose-kaolin composites' characteristics as a slow-release agent of urea fertilizer has been done. The technique used in composites' preparation is an extrusion technique using 2% CaCl2 solution as a cross-linker. The compositions of alginate-cellulose-kaolin were varied to determine their effect on composites' characteristics such as diameter, color, swelling ratio, entrapment efficiency, and release of urea. The results showed that the diameter of beads in wet condition produced ranges from 2.98 to 3.54 mm, whereas the diameter of dry beads ranges from 1.22 to 1.92 mm. The addition of cellulose and kaolin affected the color of the beads produced based on CIE Lab analysis. The value of the swelling ratio decreased with the addition of cellulose and kaolin. The entrapment efficiency of urea in beads obtained ranged from 37.25 to 45.06%. The release of urea in aqueous media showed that cellulose and kaolin's addition into the alginate affected the amount of released urea.

scholarly journals Dual delivery of nucleic acids and PEGylated-bisphosphonates via calcium phosphate nanoparticles

2019 ◽  
Author(s):  
Sofia Bisso ◽  
Simona Mura ◽  
Bastien Castagner ◽  
Patrick Couvreur ◽  
Jean-Christophe Leroux
Keyword(s):  
Calcium Phosphate ◽  
Plasmid Dna ◽  
Transfection Efficiency ◽  
Gene Transfection ◽  
Physical Stability ◽  
Entrapment Efficiency ◽  
Endosomal Escape ◽  
Particle Uptake ◽  
Success Stories

AbstractDespite many years of research and a few success stories with gene therapeutics, efficient and safe DNA delivery remains a major bottleneck for the clinical translation of gene-based therapies. Gene transfection with calcium phosphate (CaP) nanoparticles brings the advantages of low toxicity, high DNA entrapment efficiency and good endosomal escape properties. The macroscale aggregation of CaP nanoparticles can be easily prevented through surface coating with bisphosphonate conjugates. Bisphosphonates, such as alendronate, recently showed promising anticancer effects. However, their poor cellular permeability and preferential bone accumulation hamper their full application in chemotherapy. Here, we investigated the dual delivery of plasmid DNA and alendronate using CaP nanoparticles, with the goal to facilitate cellular internalization of both compounds and potentially achieve a combined pharmacological effect on the same or different cell lines. A pH-sensitive poly(ethylene glycol)-alendronate conjugate was synthetized and used to formulate stable plasmid DNA-loaded CaP nanoparticles. These particles displayed good transfection efficiency in cancer cells and a strong cytotoxic effect on macrophages. The in vivo transfection efficiency, however, remained low, calling for an improvement of the system, possibly with respect to the extent of particle uptake and their physical stability.Graphical abstract

scholarly journals DIACEREIN-LOADED NIOSOMES (DC-NS): A NEW TECHNIQUE TO SUSTAIN THE RELEASE OF DRUG ACTION

2022 ◽  
pp. 156-163
Author(s):  
RASHAD M. KAOUD ◽  
EMAN J. HEIKAL ◽  
TAHA M. HAMMADY
Keyword(s):  
Physical Stability ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Stability Study ◽  
Molar Ratios ◽  
Tween 40 ◽  
A New Technique ◽  
The Stability ◽  
Tween 60

Objective: The study's main goal is to develop a suitable niosomes (NS) encapsulated drug for anti-inflammatory effects such as diacerein (DC) and to evaluate the system's vesicle size (VS), entrapment efficiency (EE %), physical stability and in vitro release. Methods: Tween (40 and 60), cholesterol, and stearylamine were used in a 1:1:0.1 molar ratios as non-ionic surfactants. Thin film hydration was used to create the NS. Results: The higher EE% was observed with NS (F11) prepared from tween 60, cholesterol and 2.5 min sonication. These formulations' release patterns were Higuchi diffusion and first order. For the stability study, NS formulations were stored at temperature between 2-8 °C for 60 d retains the most drugs when compared to room and high temperature conditions. Conclusion: The findings of this study have conclusively shown that after NS encapsulation of DC, drug release is prolonged at a constant and controlled rate.

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