Pharmacokinetic performance of the nitrendipine intravenous submicron emulsion in rats

Development and optimization of nanoemulsion based gel for enhanced transdermal delivery of nitrendipine using box-behnken statistical design

Objective: The purpose of present research was to develop and statistically optimize nitrendipine nanoemulsion gel for transdermal delivery using box-behnken statistical design.Method: The nanoemulsion formulations bearing nitrendipine were prepared by application of ternary phase diagram and spontaneous emulsification method. Box-behnken design was employed for the optimization of nitrendipine loaded nanoemulsion. The independent variables were oil, surfactant and co-surfactant while globule size, drug content and zeta potential were dependent variables. The optimized nanoemulsion formulation was incorporated into gel and evaluated for in-vitro release, ex-vivo permeation studies, confocal laser scanning microscopy, skin irritation and histopathological studies.Results: The optimized formulation through box-behnken statistical design showed globule size of 20.43 ± 1.50 nm, drug content of 97.05 ± 1.77% and zeta potential of -15.45 ± 0.35 mV. The ex-vivo study confirmed the enhanced delivery of nitrendipine from nanoemulsion gel than compare to drug solution by virtue of better permeation and solubility. Nanoemulsion gel was proved significantly superior by confocal laser scanning microscopy for satisfactory permeation and distribution of gel, deep into the rat skin. The optimized gel was found with no allergic dermal effects and was proved safe by histopathological studies for transdermal application.Conclusions: Results reveals that developed nitrendipine nanoemulsion gel overcomes the limitation of low penetration and accentuate permeation through albino Wistar rat skin. It was concluded that nanoemulsion gel could be utilized as a potential carrier for transdermal delivery of nitrendipine.

Preparation of a Mesoporous Structure of SnO2 for Increasing the Oral Bioavailability and Dissolution Rate of Nitrendipine

In this study, mesoporous SnO₂ (MSn) with a three-dimensional mesoporous structure was prepared using MCM-48 as the template in order to increase the oral bioavailability and dissolution rate of insoluble drugs. The model drug, nitrendipine (NDP), was loaded into the MSn by the adsorption method. The structural features of MSn were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and N₂ adsorption (desorption) analysis. NDP was existed in the pore channels of MSn in an amorphous state, which was characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). MSn showed a good biocompatibility in the cell toxicity assay for Caco-2 cells. In vitro dissolution results suggested that MSn could significantly enhance the dissolution rate of NDP compared with commercial NDP tablets. Pharmacokinetic studies indicated that NDP-MSn tablets effectively enhanced the oral bioavailability of NDP. In conclusion, MSn was found to be a potential carrier for improving the solubility of insoluble drugs.

Solubility and Thermodynamic Analysis of Antihypertensive Agent Nitrendipine in Different Pure Solvents at the Temperature Range of 298.15 to 318.15°K

The aim of the present study was to ascertain the solubility of nitrendipine (NP), an antihypertensive drug in six different pure solvents such as water, ethyl acetate (EA), ethanol, isopropyl alcohol (IPA), polyethylene glycol-400 (PEG-400), and Transcutol at temperature from 298.15 to 318.15 K under atmospheric pressure (p) of 0.1 MPa. Experimental solubility data of NP was fitted with Apelblat and ideal models. The mole fraction solubility of NP was found maximum in PEG-400 (6.85 × 10^-2 at 318.15 K) followed by Transcutol (4.65 × 10^-2 at 318.15 K), EA (1.68 × 10^-2 at 318.15 K), ethanol (2.83 × 10^-3 at 318.15 K), IPA (2.69 × 10^-3 at 318.15 K), and water (1.29 × 10^-7 at 318.15 K). The dissolution activity of NP was observed as an endothermic, spontaneous, and an entropy-driven in most of studied pure solvents. The solubility data of NP obtained in the present study could be useful in purification, recrystallization, and dosage forms design of NP.

Nanotechnology Based Approaches for Enhancing Oral Bioavailability of Poorly Water Soluble Antihypertensive Drugs

Oral administration is the most convenient route among various routes of drug delivery as it offers high patient compliance. However, the poor aqueous solubility and poor enzymatic/metabolic stability of drugs are major limitations in successful oral drug delivery. There are several approaches to improve problems related to hydrophobic drugs. Among various approaches, nanotechnology based drug delivery system has potential to overcome the challenges associated with the oral route of administration. Novel drug delivery systems are available in many areas of medicine. The application of these systems in the treatment of hypertension continues to broaden. The present review focuses on various nanocarriers available in oral drug administration for improving solubility profile, dissolution, and consequently bioavailability of hydrophobic antihypertensive drugs.

Cinnamaldehyde in a Novel Intravenous Submicrometer Emulsion: Pharmacokinetics, Tissue Distribution, Antitumor Efficacy, and Toxicity

The purpose of our research is to find a new lipid emulsion to deliver a low water-soluble compound, cinnamaldehyde (CA). Its characteristics, pharmacokinetics, antitumor efficacy, and toxicity were evaluated. The mean particle size, zeta potential, and encapsulation efficiency of the submicromemter emulsion of CA (SME-CA) were 130 ± 5.92 nm, -25.7 ± 6.00 mV, and 99.5 ± 0.25%, respectively. The area under the curve from 0 h to termination time (AUC(0-t)) of SME-CA showed a significantly higher value than that of CA (589 ± 59.2 vs 375 ± 83.5 ng h/L, P < 0.01). Tissue distribution study showed various changes; among them, a 27% higher concentration was found in brain tissue when using SME-CA at 15 min after administration. For the efficacy evaluation, SME-CA exhibited 8- and 11-fold antitumor activity in the depression of HeLa and A549 cell lines with the IC50 decreasing to 0.003 and 0.001 mmol/L, respectively. The LD50 values of CA and SME-CA in mice were 74.8 and 125 mg/kg, suggesting increased safety from the new formulation. The new formulation exhibited lower toxicity, higher antitumor activity, and a more satisfactory pharmacokinetic property, which displayed great potential for future pharmacological application.