Synchronous delivery of felodipine and metoprolol tartrate using monolithic osmotic pump technology

Microfluidics for Drug Development: From Synthesis to Evaluation

Drug development is a long process whose main content includes drug synthesis, drug delivery, and drug evaluation. Compared with conventional drug development procedures, microfluidics has emerged as a revolutionary technology in that it offers a miniaturized and highly controllable environment for bio(chemical) reactions to take place. It is also compatible with analytical strategies to implement integrated and high-throughput screening and evaluations. In this review, we provide a comprehensive summary of the entire microfluidics-based drug development system, from drug synthesis to drug evaluation. The challenges in the current status and the prospects for future development are also discussed. We believe that this review will promote communications throughout diversified scientific and engineering communities that will continue contributing to this burgeoning field.

A novel preparative method for nanoparticle albumin-bound paclitaxel with high drug loading and its evaluation both in vitro and in vivo

We developed a novel preparative method for nanoparticle albumin-bound (nab) paclitaxel with high drug loading, which was based on improved paclitaxel solubility in polyethylene glycol (PEG) and self-assembly of paclitaxel in PEG with albumin powders into nanoparticles. That is, paclitaxel and PEG were firstly dissolved in ethanol, which was subsequently evaporated under vacuum. The obtained liquid was then mixed with human serum albumin powders. Thereafter, the mixtures were added into phosphate-buffered saline and nab paclitaxel suspensions emerged after ultrasound. Nab paclitaxel was finally acquired after dialysis and freeze drying. The drug loading of about 15% (W/V) were realized in self-made nab paclitaxel, which was increased by approximately 50% compared to 10% (W/V) in Abraxane. Now this new preparative method has been authorized to obtain patent from China and Japan. The similar characteristics of self-made nab paclitaxel compared to Abraxane were observed in morphology, encapsulation efficiency, in vitro release, X-ray diffraction analysis, differential scanning calorimetry analysis, and circular dichroism spectra analysis. Consistent concentration-time curves in rats, biodistributions in mice, anti-tumor activities in mice, and histological transmutation in mice were also found between Abraxane and self-made nanoparticles. In a word, our novel preparative method for nab paclitaxel can significantly improve drug loading, obviously decrease product cost, and is considered to have potent practical value.

Effects of Borneol on the Release of Compound Danshen Colon-Specific Osmotic Pump Capsule In Vitro and Pharmacokinetics Study in Beagle Dogs

Borneol can enhance the bioavailability of several other drugs by opening the blood-brain barrier and inhibiting P-glycoprotein (P-gp) efflux. However, whether borneol will impact the bioavailability and the mechanism of compound Danshen colon-specific osmotic pump capsule (CDCOPC) remains unclear. This study aimed to determine the effects of borneol on the in vitro release and in vivo pharmacokinetic characteristics of CDCOPC. Besides, the in vitro release behavior of CDCOPC was further assessed by chromatographic fingerprints. The in vitro release studies showed that borneol followed the zero-order release and hardly impacted the in vitro release of Salvia miltiorrhiza and Panax notoginseng in CDCOPC. Moreover, as revealed from the similarity results of fingerprints, the in vitro release of different components of CDCOPC was almost simultaneous. Compared with the commercially available tablets, the pharmacokinetics studies suggested that both CDCOPCs containing and lacking borneol could significantly prolong the retention time of these effective components; their average relative bioavailability values increased to 448.70% and 350.97%, respectively. Notably, borneol significantly improved the relative bioavailability of some components of CDCOPC, such as salvianolic acid B (SAB), tanshinone IIA (Tan IIA), notoginsenoside R₁ (R₁), ginsenoside Rg₁ (Rg₁), and ginsenoside Re (Re) from CDCOPC, while it slightly impacted ginsenoside Rb₁ (Rb₁) and ginsenoside Rd (Rd). Summarily, borneol is capable of improving the bioavailability of some effective components in CDCOPC, which is critical to design with CDCOPC for enhanced bioavailability. This study could also help reveal the composition principle of the compound Danshen formula (CDF).

Visualized analysis and evaluation of simultaneous controlled release of metformin hydrochloride and gliclazide from sandwiched osmotic pump capsule

The aim of this study was to develop the Metformin Hydrochloride and Gliclazide (MH-GZ) sandwiched osmotic pump capsule which could overcome the problems associated with short half-life and burst release. The system could deliver drugs with different solubility simultaneously at zero-order rate, in which MH-GZ were filled in both sides of the push layer respectively. The single factor and orthogonal test were employed to obtain the optimized formulation with the evaluation index of similarity factor (ƒ₂). R language was used to visualized analyze the main influence factors of drug release and their correlations. Pharmacokinetic study was performed in beagle dogs compared to the marketed conventional product, which showed decreased C_max, prolonged T_max, and improved bioavailability, independent of pH and agitational speed but related to osmotic pressure differences across the semi permeable membrane. The designed sandwiched osmotic pump capsule proposed a promising substitute for the marketed product for the treatment of type 2 diabetes.

Development and Evaluation of Controlled and Simultaneous Release of Compound Danshen Based on a Novel Colon-Specific Osmotic Pump Capsule

In the study, we developed a novel oral dosage form of Compound Danshen to resolve the problems of low bioavailability, disequilibrium in drug release, and stomach degradation of active components of Compound Danshen in conventional formulas. A colon-specific osmotic pump capsule (COPC) of Compound Danshen was prepared using a semipermeable shell with the core components. Using a single-factor method, we obtained the optimal formulation that consisted of Salvia miltiorrhiza extract, Panax notoginseng extract, Borneol, sodium chloride, polyethylene oxide wsr-N10, hydroxypropyl-β-cyclodextrin, and ludipress. Moreover, in vitro dissolution test showed simultaneous releases of active ingredients from Compound Danshen COPC over 12 h at pH 7.8, displaying zero-order release characteristics. The impetus of drug release mainly depended on the difference in osmotic pressure across the capsule shell. Next, scanning electron microscopy showed morphological changes in the capsule shell during the dissolution test. More importantly, pharmacokinetic study in beagle dogs indicated that relative bioavailability was 330.58% and retention time was greatly prolonged in Compound Danshen COPC, compared with those in marketed Compound Danshen tablet products. Finally, in vivo imaging studies in beagle dogs showed that COPC was stable in gastrointestinal tract and the drug was specifically released in the colon region. A colon-specific osmotic pump capsule (COPC) of Compound Danshen was developed and optimized to achieve simultaneous zero-order release of multiple active components of Compound Danshen in the colon. More importantly, the COPC have proved to improve the bioavailability and prolong the retention time of Compound Danshen, compared with those in a marketed product.