Formulation and pharmacokinetic evaluation of once-daily sustained-released system of nifedipine with solid dispersion and coating techniques

Supercritical fluid technology as a strategy for nifedipine solid dispersions formulation: In vitro and in vivo evaluation

Supercritical fluid technology (SFT) is an insufficiently investigated approach for the production of solid dispersions, it is environmentally acceptable and has a high potential for application in the pharmaceutical industry. The aim of this work was to formulate and characterize nifedipine solid dispersions (SDs) produced by the SFT and compare the results with ones obtained by the classical solvent based kneading method. The following in vitro tests were conducted: assay and yield, solvent residues, solid state characterization (FTIR, DSC, XRD), flowability, hygroscopicity, solubility, dissolution and stability. Additionally, bioavailability was examined on an animal model (Wistar rats). The formulation selection for in vivo study was performed using the multilevel categoric experimental design and the health risk assessment. Solid state characterization revealed that formulation obtained by the SFT method and higher ratio of polymer (1:5) have had nifedipine in completely amorphous form. Polymer ratio and method of SDs preparation do influence the investigation characteristics. Dissolution rate was fastest in SDs prepared by the SFT and higher polymer ration (1:5). In vivo data of selected SDs prepared by the kneading (ratio 1:1) and the SFT (ratio 1:5) showed alteration in pharmacokinetic profile after i.v. and p.o. application.

Novel Curcumin Derivative-Decorated Ultralong-Circulating Paclitaxel Nanoparticles: A Novel Delivery System with Superior Anticancer Efficacy and Safety

Purpose

Paclitaxel (PTX) has been widely utilized for the treatment of breast cancer. However, drawbacks, such as poor aqueous solubility, rapid blood clearance and severe toxicity, greatly reduce its efficacy and safety. Herein, a novel self-developed curcumin derivative (CUD) was chosen as the carrier to develop a long-acting PTX nano-delivery system (PTX-Sln@CUD) in order to improve its pharmacokinetic behavior, anti-breast cancer efficacy and safety.

Methods

PTX-Sln@CUD was prepared using solid dispersion and ultrasonic technology. Relevant physical and chemical properties, including stability and release behavior, were characterized. The clearance of PTX-Sln@CUD in vivo was studied by pharmacokinetic experiments. The anti-tumor activity of PTX-Sln@CUD was investigated in vitro and in vivo. Hemolysis experiments, acute toxicity and cumulative toxicity studies were performed in mice to determine the safety of PTX-Sln@CUD.

Results

The average particle size, PDI, Zeta potential, encapsulation efficiency and loading efficiency of the PTX-Sln@CUD were 238.5 ± 4.79 nm, 0.225 ± 0.011, −33.8 ± 1.26 mV, 94.20 ± 0.49% and 10.98 ± 0.31%, respectively. PTX-Sln@CUD was found to be stable at room temperature for half a year. The cumulative release rates of PTX-Sln@CUD at 24, 96 and 168 h were 17.98 ± 2.60, 57.09 ± 2.32 and 72.66 ± 4.16%, respectively, which were adherent to zero-order kinetics. T_1/2, MRT _(0-t) and AUC _(0-t) of the PTX-Sln@CUD group were 4.03-fold (44.293 h), 7.78-fold (38.444 h) and 6.18-fold (14.716 mg/L*h) of the PTX group, respectively. PTX-Sln@CUD group demonstrated stronger anti-breast cancer activity than the PTX group. Importantly, the PTX-Sln@CUD group was safer compared to the PTX group both in vitro and in vivo.

Conclusion

PTX-Sln@CUD was verified as promising therapeutic nanoparticles for breast cancer and provided a novel strategy to solve the problem of low efficacy and poor safety of clinical chemotherapy drugs.

The Effects of a Novel Curcumin Derivative Loaded Long-Circulating Solid Lipid Nanoparticle on the MHCC-97H Liver Cancer Cells and Pharmacokinetic Behavior

Purpose

Methods

Results

Conclusion

Integration of lornoxicam nanocrystals into hydroxypropyl methylcellulose-based sustained release matrix to form a novel biphasic release system

The study aims to (a) enhance the solubility of a poorly soluble drug by optimization of nanocrystal formulation using the top-down approach and (b) modify the release profile of this drug, which exhibits a short elimination half-life, by the integration of a fast-release phase containing the optimized nanocrystals and a sustained-release phase in a compression-coated tablet. Nanocrystals of the model drug (lornoxicam; LNX) was prepared by simultaneous application of jet-milling and ball-milling techniques. Investigation of the precipitation inhibition capacity, thermal property, and interaction of different polymers with the drug revealed polyvinyl pyrrolidone K30 (PVP) as the most effective stabilizer for nanocrystals. The immediate-release layer containing the optimized nanocrystals (size of 279.5 ± 11.25 nm and polydispersity index of 0.204 ± 0.01) was then compressed on a zero-order sustained-release matrix core using different derivatives of hydroxypropyl methylcellulose (HPMC). Application of the Design of Experiment approach (DoE) was applied to optimize the formulation of tablet. Analysis of drug concentration in dog plasma by liquid chromatography-tandem mass spectrometry demonstrated an improvement in the release behavior of LNX from the optimal compression-coated tablet integrating a HPMC-based sustained release matrix core and a PVP-stabilized lornoxicam nanocrystals coating layer compared to the reference product.