Engineering 5-flourouracil and leucovorin-loaded vesicular systems for possible colon specific delivery: In vitro evaluation and real time cell assay against HCT-116 colon cell lines.

5-flourouracil (5-FU) is typically modulated with leucovorin (LEU) in clinical practice to improve clinical efficacy and patient survival rates. However, this combination has undesirable side effects and makes 5-FU more toxic. Hence, integrating a vesicular system (proniosomes) with another delivery vehicle may improve drug targeting, while resolving the aforementioned drawbacks. This study aimed to engineer 5-FU/LEU proniosomes for possible delivery to the colon. The modified slurry approach was used to create drug-loaded proniosomes (150 mg/9 g of carrier) using both water-soluble (dextrin (DEX) and lactose (LAC)) and insoluble (Neusilin FH2 (NEU)) carriers. The powdered formulations were filled into Eudragit S100 (10 %)-coated capsules or Eudragit FS 30D capsules for enteric- or colon-specific delivery. In vitro evaluations (flow properties, powder X-ray diffractometry (XRD) analysis, particle size analysis, entrapment efficiency, drug release, scanning electron microscopy (SEM), polydispersity index, Fourier transform infrared spectroscopy (FTIR), and stability studies) were performed on the formulations. An in vitro cytotoxicity test [real-time cell assay (RTCA)] against HCT-116 colon cancer cell lines was performed using the optimized formulation. In vitro evaluations showed that the nanoparticles had good physicochemical properties. RTCA studies showed sustained cell death with the formulations compared to the pure drug and placebo. The sequential drug release of the colon-targeted capsules containing 5-FU and LEU- loaded proniosomes showed negligible drug release in SGF (pH 1.2) and phosphate buffer solution (pH 6.8) (approximately 11 %) but profound drug release (>80 %) at pH 7.4. Drug-loaded proniosomes engineered for colon targeting (Eudragit S100 (10 %) capsules or Eudragit FS 30D capsules) showed good colon-specific targeting and favorable in vitro cytotoxicity profiles.

Evaluation of the Antimicrobial Activity of a Formulation Containing Ascorbic Acid and Eudragit FS 30D Microparticles for the Controlled Release of a Curcumin-Boric Acid Solid Dispersion in Turkey Poults Infected with Salmonella enteritidis: A Therapeutic Model.

The selection of components within a formulation or for treatment must stop being arbitrary and must be focused on scientific evidence that supports the inclusion of each one. Therefore, the objective of the present study was to obtain a formulation based on ascorbic acid (AA) and Eudragit FS 30D microparticles containing curcumin-boric acid (CUR-BA) considering interaction studies between the active components carried out via Fourier transform infrared spectrometry (FTIR) and differential scanning calorimetry (DSC) to minimize antagonistic effects, and comprehensively and effectively treat turkey poults infected with Salmonella enteritidis (S. enteritidis). The DSC and FTIR studies clearly demonstrated the interactions between AA, BA, and CUR. Consequently, the combination of AA with CUR and/or BA should be avoided, but not CUR and BA. Furthermore, the Eudragit FS 30D microparticles containing CUR-BA (SD CUR-BA MP) showed a limited release of CUR-BA in an acidic medium, but they were released at a pH 6.8-7.0, which reduced the interactions between CUR-BA and AA. Finally, in the S. enteritidis infection model, turkey poults treated with the combination of AA and SD CUR-BA MP presented lower counts of S. enteritidis in cecal tonsils after 10 days of treatment. These results pointed out that the use of an adequate combination of AA and CUR-BA as an integral treatment of S. enteritidis infections could be a viable option to replace the indiscriminate use of antibiotics.

Preparing simvastatin nanoparticles by a combination of pH-sensitive and timed-release approaches for the potential treatment of ulcerative colitis.

In this study, an emulsion solvent evaporation method was used to produce Eudragit RL (ERL) nanoparticles (NPs) loaded with simvastatin (SIM) for the treatment of ulcerative colitis (UC). Accordingly, the effects of different formulation variables on the properties of NPs were evaluated using the Box-Behnken design. The optimized NPs were then coated by Eudragit FS30D (EFS30D). Drug release was studied in different physiological environments. Colitis was induced by 3% of acetic acid in rats, which received NPs of SIM (10 mg/kg/day), mesalazine (150 mg/kg/day), blank NPs and normal saline orally for 5 days. Macroscopic histopathological evaluation and biochemical analysis, including myeloperoxidase (MPO) activity and malondialdehyde (MDA) level in the colon tissues, were carried out in this study. The optimized SIM-ERL NPs showed the particle size of 182.48 ± 4.57 nm, the polydispersity index of 0.29 ± 0.12, the zeta potential of 26.45 ± 4.57 mV, drug loading % of 34.64 ± 0.48, the encapsulation efficiency % of 98.68 ± 0.69, and the release efficiency % of 35.78 ± 1.37. Coating the optimized NPs with EFS30D caused an increase in particle size and a decrease in the zeta potential of NPs. The optimized SIM-EFS30D/RL NPs improved the macroscopic and histopathological scores. Also, MPO activity and MDA level were reduced significantly by NPs, as compared to the control group. Therefore, this drug delivery system can be an alternative to the previous treatments of UC.

Development of enoxaparin sodium polymeric microparticles for colon-specific delivery.

BACKGROUND AND AIMS: Recent studies have shown that low molecular weight heparins are effective in the treatment of inflammatory bowel disease. Therefore, there is considerable interest in the development of an oral colonic delivery pharmaceutical system allowing targeted release of heparin in the inflamed tissue. The objective of this study was to prepare microparticles for the oral administration and colonic release of enoxaparin and to evaluate the influence of certain formulation factors on their characteristics. METHODS: Microparticles were prepared by water/oil/water double emulsion technique followed by solvent evaporation. The influence of several formulation factors on the characteristics of microparticles were evaluated. The formulation factors were alginate concentration in the inner aqueous phase, polymer (Eudragit(®) FS 30D and Eudragit(®) RS PO) concentration in the organic phase and ratios between the two polymers. The microparticles were characterized in terms of morphology, size, entrapment efficiency and enoxaparin release. RESULTS: The results showed that increasing sodium alginate percentage reduced the encapsulation efficiency of enoxaparin and accelerated enoxaparin release. Regarding the influence of the two polymers, reducing polymer concentration in the organic phase led to a smaller size of microparticles, a lower entrapment efficiency and an important retardation of enoxaparin release. The formulation prepared with Eudragit(®) FS 30D limited the release to a maximum of 3% in gastric simulated environment, a specific characteristic of oral systems for colonic delivery, and fulfilled our objective to delay the release. CONCLUSIONS: Microparticles prepared with Eudragit(®) FS 30D represent a suitable and potential oral system for the colonic delivery of enoxaparin.

pH-sensitive poly(lactide-co-glycolide) nanoparticle composite microcapsules for oral delivery of insulin.

This study proposes a new concept of pH-sensitive poly(lactide-co-glycolide) (PLGA) nanoparticle composite microcapsules for oral delivery of insulin. Firstly, insulin-sodium oleate complex was prepared by the hydrophobic ion pairing method and then encapsulated into PLGA nanoparticles by the emulsion solvent diffusion method. In order to reduce the burst release of insulin from PLGA nanoparticles and deliver insulin to specific gastrointestinal regions, hence to enhance bioavailability of insulin, the PLGA nanoparticles were further encapsulated into Eudragit(®) FS 30D to prepare PLGA nanoparticle composite microcapsules by organic spray-drying method. The preparation was evaluated in vitro and in vivo, and the absorption mechanism was discussed. The in vitro drug release studies revealed that the drug release was pH dependent, and the in vivo results demonstrated that the formulation of PLGA nanoparticle composite microcapsules was an effective candidate for oral insulin delivery.