Efficient extraction of phycobiliproteins from dry biomass of Spirulina platensis using sodium chloride as extraction enhancer.

An efficient strategy for phycobiliprotein extraction from Spirulina platensis dry biomass has been developed by using NaCl as an enhancer. Different sodium ion and chloride ion salts were screened, and NaCl was selected as the most appropriate solvent for phycobiliprotein extraction. The extraction parameters with NaCl were optimized using response surface methodology. Under optimal operating conditions, a phycobiliprotein extraction rate of 74.8 % and a phycocyanin extraction yield of 102.4 mg/g with a purity of 74.0 % were achieved. Adding NaCl resulted in smaller fragments and destroyed the cell integrity of S. platensis, facilitating phycobiliprotein exudation. The secondary structure and antioxidant activity of phycobiliproteins were not affected by NaCl extraction. The stability of the phycobiliproteins was improved by adding NaCl. This study provides a potential method for phycobiliprotein extraction with high efficiency and good quality using an inexpensive extraction enhancer.

Current Therapeutic Strategy in the Nasal Delivery of Insulin: Recent Advances and Future Directions.

BACKGROUND: Insulin (INS) has been used in the treatment of diabetes mellitus. Due to its large molecular weight and short half-life, it has been usually administered subcutaneously accompanied with side effects such as the possibility of hypoglycemia episodes, weight gain and inadequate post-meal glucose control. OBJECTIVE: In order to overcome these limitations, alternative delivery routes of insulin are expected to provide better safety and compliance for the patient. Non-invasive insulin delivery system represents one of the most challenging goals for pharmaceutical industry. Nasal insulin delivery has been extensively studied as an alternative to subcutaneous injection for the treatment of diabetes. The pharmacokinetic profile of nasal insulin is similar to that obtained by intravenous injection. RESULT & CONCLUSION: This review discusses the most recent developments in nasal insulin administration technology. Firstly, the structure and physiology of the nasal cavity are introduced. Then, the advantages and disadvantages of nasal administration are discussed. Next, the methods of enhancing nasal insulin absorption and the dosage forms for insulin nasal administration are described. Furthermore, new therapeutic indications of nasal insulin administration were also investigated. Finally, the future development and respective technology of nasal insulin administration are prospected.

Spray-dried curcumin nanoemulsion: A new road to improvement of oral bioavailability of curcumin.

In this study a new soluble solid curcumin nanoemulsion powder was prepared using spray-drying technology to improve the solubility and bioavailability of curcumin. The liquid nanoemulsion consisted of curcumin, Capryol 90, Transcutol P, and Cremophor RH40. The solid nanoemulsion was prepared by spray-drying the liquid nanoemulsion in laboratory spray dryer, using lactose as solid carrier. The in vitro release from powder formulation was 97.6% within 15 min while the release from the curcumin crystalline was about 10%. An oral pharmacokinetic study was conducted in rats and the relative bioavailability of spray-dried curcumin powder significantly increased compared with that of curcumin crystalline. The Cmax value of solid curcumin nanoemulsion powder was 5.5-fold greater than the value of the curcumin crystalline in aqueous suspension. The absorption mechanism of the spray-dried curcumin powders was discussed. The results indicate that spray-drying in combination with nanoemulsion was a powerful methodology for improving the dissolution rate and oral bioavailability of curcumin.

Evaluation of High-Performance Curcumin Nanocrystals for Pulmonary Drug Delivery Both In Vitro and In Vivo.

This paper focused on formulating high-performance curcumin spray-dried powders for inhalation (curcumin-DPIs) to achieve a high lung concentration. Curcumin-DPIs were produced using wet milling combined with the spray drying method. The effects of different milling times on particle size and aerodynamic performance were investigated. The curcumin-DPIs were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), and in vitro dissolution. Furthermore, the in vivo pharmacokinetic behavior and tissue distribution after pulmonary administration were also evaluated. Results showed that the drug dissolution was significantly enhanced by processing into curcumin-DPIs. The aerodynamic results indicated that the DPIs displayed a good aerosol performance. The plasma curcumin concentration was obviously enhanced by inhalation, and most of the curcumin-DPIs were deposited in the lung. This study demonstrated that inhalation was an effective way to carry drug to the lung, and curcumin-DPIs were hopeful for lung cancer treatment in the future.

Enhanced antitumor efficacy of folate targeted nanoparticles co-loaded with docetaxel and curcumin.

BACKGROUND: The current study aimed to investigate whether the novel folate (FT) modified nanoparticles (NPs) co-loaded with docetaxel (DT) and curcumin (CU) (named as FT-NPs) could enhance the delivery efficiency to tumor compared with the NPs without FT (non-targeted NPs). METHODS: FT-NPs were successfully formulated in this article. In vitro cytotoxic activity against A549 cells and in vivo antitumor activity of FT-NPs in S180 cell bearing mice were conducted. Cellular uptake test was used to evaluate uptake efficiency of FT-NPs. Histological observation was used to determine the lung security. Besides, the physical chemical properties such as stability, particle size, zeta potential, drug encapsulation efficiency, transmission electron microscopy (TEM) were also conducted. RESULTS: FT-NPs exhibited stronger growth inhibition effects on A549 cells compared with non-targeted NPs, moreover, the novel FT-NPs indicated more effective antitumor efficacy in inhibiting tumor growth. Confocal laser scanning microscopy indicated that the uptake of FT-NPs was facilitated and effective. Histological observation meant that FT-NPs were biocompatible and appropriate for pulmonary administration. CONCLUSION: These results confirmed that FT-NPs with relatively high drug loading capacity could effectively inhibit tumor growth and reduce toxicity. The novel FT-NPs could produce as an outstanding nanocarrier for the targeted treatment of cancers.

Enhancement of transdermal delivery of ibuprofen using microemulsion vehicle.

OBJECTIVES: The objective of this study was to find a stable microemulsion vehicle for transdermal delivery of ibuprofen to improve the skin permeability. MATERIALS AND METHODS: Microemulsion was prepared using different sorts of oils, surfactants and co-surfactants. Pseudo-ternary phase diagrams were used to evaluate the microemulsion domain. The effects of oleic acid and surfactant mixture on skin permeation of ibuprofen were evaluated with excised skins. RESULTS: The optimum formulation F3 consisting of 6% oleic acid, 30% Cremophor RH40/Transcutol P (2:1, w/w) and 59% water phase, showed a high permeation rate of 42.98 µg/cm(2)/hr. The mean droplet size of microemulsion was about 43 nm and no skin irritation signs were observed on the skin of rabbits. CONCLUSION: These results indicated that this novel microemulsion is a useful formulation for the transdermal delivery of ibuprofen.

Investigation of inclusion complex of cilnidipine with hydroxypropyl-ß-cyclodextrin.

The objective of this study was to improve the water-solubility and photostability of cilnidipine by complexing it with hydroxypropyl-ß-cyclodextrin (HP-ß-CD or HP-beta-CD). The interactions of cilnidipine and HP-ß-CD were characterized by ultra violet-visible (UV/VIS) spectroscopy, differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Fourier transformation-infrared (FT-IR) spectroscopy and (1)H nuclear magnetic resonance ((1)H NMR) spectroscopy to verify the formation of cilnidipine-HP-ß-CD complex inclusion. Moreover, the binding sites in the HP-ß-CD structure were also tracked through (1)H NMR spectroscopy analysis. All the characterization information proved the formation of cilnidipine-HP-ß-CD inclusion complex, and the results demonstrated the superiority of the inclusion complex in dissolution rates and photostability; in addition, the apparent solubility of cilnidipine was increased more than 10,000-fold in the presence of HP-ß-CD. The stability constant (1:1) was found to be 50,116 M(-1), suggesting a high tendency of the drug to enter the HP-ß-CD cavity. These results identified the cilnidipine-HP-ß-CD inclusion complex as an effective new approach to design a novel formulation for pharmaceutical application.