Investigation on fabrication process of dissolving microneedle arrays to improve effective needle drug distribution.

The dissolving microneedle array (DMNA) offers a novel potential approach for transdermal delivery of biological macromolecular drugs and vaccines, because it can be as efficient as hypodermic injection and as safe and patient compliant as conventional transdermal delivery. However, effective needle drug distribution is the main challenge for clinical application of DMNA. This study focused on the mechanism and control of drug diffusion inside DMNA during the fabrication process in order to improve the drug delivery efficiency.

[Preparation and in vitro embolic efficiency evaluation of hydroxycamptothecine-loaded liquid embolic agent].

The purpose of this study is to investigate the preparation of hydroxycamptothecine (HCPT)-loaded cubic crystal liquid embolic precursor solution, and evaluate its in vitro embolic efficiency. Phytantriol was used as cubic crystal liquid embolic material, and the optimal formulation was selected according to ternary phase diagram. Polarized light microscopy, differential scanning calorimetry, and small angle X-ray scattering (SAXS) were used to characterize the cubic crystal structure.

[Preparation and in vitro study on diffusion of capsaicin cubosome].

This study was to investigate the permeability and absorbability of capsaicin cubosome across abdominal skin of the SD rats in vitro. Diffusion of capsaicin cubosome and cream was performed with the modified Franz diffusion cell technique. The capsaicin cubosome showed no enhancement of skin permeation within 24 hours.

Improving oral bioavailability of metformin hydrochloride using water-in-oil microemulsions and analysis of phase behavior after dilution.

Microemulsions show significant promise for enhancing the oral bioavailability of biopharmaceutics classification system (BCS) class II drugs, but how about class III drugs remains unclear. Here we employed metformin hydrochloride (MET) as the model drug and prepared drug-loaded water-in-oil (W/O) microemulsions selecting different hydrophile-lipophile balance (HLB) surfactant systems, using HLB 8 as a cut-off. We examined the phase behaviors of microemulsions after dilution and attempted to correlate these behaviors to drug oral bioavailability.

Proniosome-derived niosomes for tacrolimus topical ocular delivery: in vitro cornea permeation, ocular irritation, and in vivo anti-allograft rejection.

The objective of this study was to develop proniosome-derived niosomes for topical ophthalmic delivery of Tacrolimus (FK506). The FK506 loaded proniosomes containing poloxamer 188 and lecithin as surfactants, cholesterol as a stabilizer, and minimal amount of ethanol and trace water reconstituted to niosomes prior to use. The stability of FK506 loaded proniosomes was assessed, and the morphology, size, zeta potential, surface tension, and entrapment efficiency of the derived niosomes were characterized, indicating they were feasible for instillation in the eyes.

A novel technology using transscleral ultrasound to deliver protein loaded nanoparticles.

This study was designed to investigate the feasibility of silk fibroin nanoparticles (SFNs) for sustained drug delivery in transscleral ultrasound. Fluorescein isothiocynate labeled bovine serum albumin (FITC-BSA, MW 66.45 kDa) was chosen as a model macromolecular protein drug and SFNs were used as nano-carrier systems suitable for ocular drug delivery.

Comparison of novel granulated pellet-containing tablets and traditional pellet-containing tablets by artificial neural networks.

Novel granulated pellets technique was adopted to prepare granulated pellet-containing tablets (GPCT). GPCT and traditional pellet-containing tablets (PCT) were prepared according to 29 formulations devised by the Design Expert 7.0, with doxycycline hydrochloride as model drug, blends of Eudragit FS 30D and Eudragit L 30D-55 as coating materials, for the comparison study to confirm the superiority of GPCT during compaction.

Formulation and evaluation of novel reverse microemulsions containing salmon calcitonin in hydrofluoroalkane propellants.

To develop reverse microemulsion as a potential strategy for pulmonary delivery of salmon calcitonin (sCT) in HFA134a propellant of pressurized metered dose inhalers (pMDIs), pluronic P85 (P85) was chosen as the most appropriate surfactant to form microemulsions containing sCT. Formulation parameters, including the surfactant and ethanol content, water content, and sCT loading, were optimized to obtain two desired pMDI formulations A and B with clear and transparent appearance, Tyndall effect, good physical stability and aerosolization properties. Aerosolization properties of the optimized pMDIs were assessed by next generation impactor (NGI) and twin-stage impactor (TSI), and the dose of sCT in each stage was assayed by HPLC.

Plasma pharmacokinetics and lung distribution of tetrahydropalmatine after topical application of cold asthma recipe extract: Feishu (BL 13) versus Non-Feishu acupoint.

Ethnopharmacological Relevance: Acupoint application of cold asthma recipe (CAR) was a traditional Chinese medicine (TCM) method, widely used as an alternative medicine for clinical prevention of the common winter diseases of asthma and bronchitis. Tetrahydropalmatine (THP) was a main active ingredient of CAR extract. The aim of this study is to compare plasma pharmacokinetics and lung distribution of THP between Feishu (FS) acupoint (BL 13) and Non-Feishu (NFS) acupoint application of CAR extract by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).

Influence of processing parameters and formulation factors on the bioadhesive, temperature stability and drug release properties of hot-melt extruded films containing miconazole.

This study investigated the processing parameters and formulation factors on the bioadhesive properties, temperature stability properties, and drug release properties of miconazole in PolyOx® and Klucel® matrix systems produced by Hot-melt Extrusion (HME) technology. Miconazole incorporated into these matrix systems were found to be stable for 8 months by X-ray diffraction (XRD). The addition of miconazole increased area under the curve (AUC) at contact time intervals of 30 and 60 sec, while the bioadhesion decreased with an increase in processing temperatures.

Percutaneous delivery of econazole using microemulsion as vehicle: formulation, evaluation and vesicle-skin interaction.

This project was carried out to exploit the feasibility of using microemulsion (ME) as an alternative carrier for percutaneous delivery econazole nitrate (ECN) and elucidate the underlying mechanism of permeation enhancement. The ME was developed based on Labrafil M 1944 Cs as oil phase, Solutol HS15 and Span 80 as surfactants, Transcutol P as cosurfactant and water as aqueous phase. The solubility of ECN was firstly determined for screening the ingredients of the system.

Comparative pharmacokinetics of tetramethylpyrazine phosphate in rat plasma and extracellular fluid of brain after intranasal, intragastric and intravenous administration.

The purpose of this study was to compare the pharmacokinetic profiles of tetramethylpyrazine phosphate (TMPP) in plasma and extracellular fluid of the cerebral cortex of rats via three delivery routes: intranasal (i.n.), intragastric (i.

The utilization of drug-polymer interactions for improving the chemical stability of hot-melt extruded solid dispersions.

Objective: Interactions between drugs and polymers were utilized to lower the processing temperature of hot-melt extrusion (HME), and thus minimize the thermal degradation of heat-sensitive drugs during preparation of amorphous solid dispersions.

Methods: Diflunisal (DIF), which would degrade upon melting, was selected as a model drug. Hydrogen bonds between DIF and polymeric carriers (PVP K30, PVP VA64, hydroxypropyl methylcellulose and Soluplus) were revealed by differential scanning calorimetry and Fourier transform infrared spectroscopy.

Development of high drug-loading nanomicelles targeting steroids to the brain.

The objective of this research was to develop and evaluate high drug-loading ligand-modified nanomicelles to deliver a steroidal compound to the brain. YC1 (5α-cholestane-24-methylene-3β, 5α, 6β, 19-tetraol), with poor solubility and limited access to the brain, for the first time, has been proved to be an effective neuroprotective steroid by our previous studies. Based on the principle of 'like dissolves like', cholesterol, which shares the same steroidal parent nucleus with YC1, was selected to react with sodium alginate, producing amphiphilic sodium alginate- cholesterol derivatives (SACDs).

Approvals of Pharmaceutical Drugs in China in the Post-Drug Registration Regulation II Era.

Objective: To delineate the impact of the revised Drug Registration Regulation (DRR II) issued in 2007 on drug approval in China and reveal the change in approval situations for new drugs and generic drugs in the post-DRR II era (2007-2011).

Methods: Data of drug approvals were collected from the database of the China Food and Drug Administration (CFDA) and were analyzed by introducing 3 ratio indicators and utilizing statistical analysis tools.

Results: In the post-DRR II era, the drug approvals showed a general trend of the following: (1) a statistically significant rise in both the absolute number and proportion of new drugs, (2) a nonsignificant change for drugs in new dosage forms, and (3) a statistically significant drop in both the absolute number and proportion of generic drugs.

Skin penetration of topically applied white mustard extract and its effects on epidermal Langerhans cells and cytokines.

White mustard (Sinapis alba L.), a traditional Chinese medicine, is widely used in China for clinical prevention and treatment of the common winter diseases of asthma and bronchitis by percutaneous administration in the summer. The present study is to investigate the skin penetration behavior of white mustard extract to elucidate the possible mechanism underlying its immune regulation activity.

Process Investigation of a Novel Compaction Technique With Pellet-Containing Granules.

Objective: The purpose of this study was to investigate the influence of the preparing process on the properties of pellet-containing granules and tablets.

Methods: Coated pellets were granulated by centrifugal granulation, and the obtained pellet-containing granules were mixed with cushioning granules and compressed into tablets. Tablets were characterized for a drug release rate as compared with the original coated pellets.

Application of hot melt extrusion for poorly water-soluble drugs: limitations, advances and future prospects.

Hot melt extrusion (HME) is a powerful technology to enhance the solubility and bioavailability of poorly water-soluble drugs by producing amorphous solid dispersions. Although the number of articles and patents about HME increased dramatically in the past twenty years, there are very few commercial products by far. The three main obstacles limiting the commercial application of HME are summarized as thermal degradation of heat-sensitive drugs at high process temperature, recrystallization of amorphous drugs during storage and dissolving process, and difficulty to obtain products with reproducible physicochemical properties.

Nanostructured cubosomes as advanced drug delivery system.

Some kinds of amphiphilic lipids can spontaneously self-assemble with a proper ratio of water to form liquid crystalline, also known as cubic phase. With a curved bi-continuous lipid bilayer and two congruent networks of water channels, cubic phases can enclose hydrophilic, amphiphilic and hydrophobic drugs for delivery. Nanostructured cubosomes, prepared by fragmentation of bulk cubic phase gels or lyotropic methods, retain the same inner structure of cubic phase and possess much larger specific surface area and lower viscosity.

Cubic phase nanoparticles for sustained release of ibuprofen: formulation, characterization, and enhanced bioavailability study.

In order to improve the oral bioavailability of ibuprofen, ibuprofen-loaded cubic nanoparticles were prepared as a delivery system for aqueous formulations. The cubic inner structure was verified by cryogenic transmission electron microscopy. With an encapsulation efficiency greater than 85%, the ibuprofen-loaded cubic nanoparticles had a narrow size distribution around a mean size of 238 nm.

Analysis of the Current Situation of Antibiotics Use in China: A Hospital-Based Perspective.

Objective: To investigate the present situation of antibiotics use in selected hospitals in China according to 2 indicators: hospital-based market sales and frequency of usage; based on this information, to assess the government's containment policies toward antibiotics overuse.

Methods: Marketing and clinical usage data of antibiotics in 420 selected hospitals from 21 major cities and 1 district in China during 2008-2011 were collected and analyzed. Usage frequency was measured by the defined daily dose (DDD) analytic approaches recommended by World Health Organization (WHO), and the growth rate of DDDs per patient was compared for 3 categories of antibiotics: nonlimited (first line), limited (second line), and specially controlled (third line).

Increasing the oral bioavailability of poorly water-soluble carbamazepine using immediate-release pellets supported on SBA-15 mesoporous silica.

Background And Methods: The aim of this study was to develop an immediate-release pellet formulation with improved drug dissolution and adsorption. Carbamazepine, a poorly water-soluble drug, was adsorbed into mesoporous silica (SBA-15-CBZ) via a wetness impregnation method and then processed by extrusion/spheronization into pellets. Physicochemical characterization of the preparation was carried out by scanning electron microscopy, transmission electron microscopy, nitrogen adsorption, small-angle and wide-angle x-ray diffraction, and differential scanning calorimetry.

Molecular modeling-based inclusion mechanism and stability studies of doxycycline and hydroxypropyl-β-cyclodextrin complex for ophthalmic delivery.

The aim of the present study was to prepare a stable complex of doxycycline (Doxy) and hydroxypropyl-β-cyclodextrin (HPβCD) for ophthalmic delivery and investigate the inclusion mechanism and the inclusion effects on the stability of Doxy. The Doxy/HPβCD complex was prepared by solution stirring and then characterized by scanning electron microscopy and ultraviolet spectroscopy. Based on results of nuclear magnetic resonance, molecular model of Doxy/HPβCD complex was established using computational simulation of PM3 method implemented in Gaussian 03.

Development of amphotericin B-loaded cubosomes through the SolEmuls technology for enhancing the oral bioavailability.

The oral administration of amphotericin B (AmB) has the major drawback of poor bioavailability. The aim of this work was to evaluate the potential of AmB-loaded cubosomes as an oral formulation with improved bioavailability. This manuscript firstly developed AmB-loaded cubosomes by using the SolEmuls technology.