Lipid-core nanocapsules restrained the indomethacin ethyl ester hydrolysis in the gastrointestinal lumen and wall acting as mucoadhesive reservoirs

Advances in natural compound-based nanomedicine and the interaction with gut microbiota in ulcerative colitis therapy

Ulcerative colitis (UC) is a chronic inflammatory bowel disorder of the large intestine. Previous studies have indicated that the gut microbiota plays an important role in the triggers, development, and treatment response of UC. Natural active molecules and their nanoformulations show huge potential for treating UC. The nanoparticles can regulate the gut microbiota and metabolites, whereas gut microbiota-mediated effects on nanomedicines can also bring additional therapeutic benefits. Therefore, this review aims to integrate current research on natural active molecule-based nanomedicines for UC therapy and their interaction with the gut microbiota. Here, this discussion focuses on the effects and functions of gut microbiota and metabolites in UC. The use of active molecules and the nanoformulation from natural compounds for UC therapy have been provided. The interactions between the gut microbiota and nanomedicines are derived from natural products and elucidate the possible biological mechanisms involved. Finally, the challenges and future directions for enhancing the therapeutic efficacy of nanomedicine in treating UC are proposed.

The Anti-Arthritic Activity of Diclofenac Lipid-Core Nanocapsules: Stereological Analysis Showing More Protection of Deep Joint Components

Diclofenac is the most prescribed nonsteroidal anti-inflammatory drug worldwide and is used to relieve pain and inflammation in inflammatory arthritis. Diclofenac is associated with serious adverse effects, even in regular-dose regimens. Drug delivery systems can overcome this issue by reducing adverse effects and optimizing their efficacy. This study evaluated the activity of lipid-core nanocapsules loaded with diclofenac (DIC-LNCs) in an experimental model of adjuvant-induced arthritis. The diclofenac nanoformulation was obtained via self-assembly. A stereological analysis approach was applied for the morphological quantification of the volume, density, and cellular profile count of the metatarsophalangeal joints of rats. Proinflammatory cytokines and biochemical profiles were also obtained. Our results showed that the diclofenac nanocapsule DIC-LNCs were able to reduce arthritis compared with the control group and the DIC group. DIC-LNCs efficiently reduced proinflammatory cytokines, C-reactive protein, and xanthine oxidase levels. Additionally, DIC-LNCs reduced the loss of synoviocytes and chondrocytes compared with the DIC (p < 0.05) and control groups (p < 0.05). These data suggest that DIC-LNCs have anti-arthritic activity and preserve joint components, making them promising for clinical use.

Innovated pirfenidone loaded lecithin nanocapsules for targeting liver fibrosis: Formulation, characterization and in vivo study

Increasing interest in developing antifibrotic therapies became a paramount priority due to the globally raised incidence of deaths secondary to hepatic cirrhosis. This work deals with the development of innovative antifibrotic pirfenidone -loaded lecithin core nanocapsules. This with the intention to target the liver and to increase the drug bioavailability, reducing drug liver toxicity, and studying the associated hepatic microenvironment changes. PFD-loaded lecithin nanocapsules (PFD-LENCs) were prepared using the natural lipoid S45 for its dual benefits of being both a lipid and an amphiphilic surfactant. The selected formulation exhibited in vitro sustained drug release up to 24 h compared to free PFD, which is consistent with the studied pharmacokinetic profile. The studied cytotoxicity of PFD as well as PFD-LENCs exhibited negligible cytotoxicity in normal oral epithelial cells. For exploring the capability of the PFD-LENCs in reaching the liver; in vivo tracing using CLSM, in vivo biodistribution to the vital organs were conducted and electron microscopic examination for depicting nanoparticles in liver tissue was performed. Results revealed the capability of the prepared fluorescent LENC2 in reaching the liver, PFD-LENCs detection in the Disse space of the liver and the significant accumulation of PFD-LENCs in liver tissue compared to the other tested organs. The assessment of the necro-inflammatory, antioxidant and the anti-fibrotic effect of PFD-LENCs (50 & 100 mg/kg) exhibited a significant decrease of liver enzymes, TNF-α, TGF-β, Col-1, α-SMA, and TIMP-1, and a significant increase of catalase enzyme and MMP2 compared to free PFD. EM studies, revealed often detection of dendritic cells in PFD-LENCs (100 mg/kg) treated mice and abnormal collagen structure which can represent an adjunct contribution to the antifibrotic mechanism of PFD-LENCs. In conclusion, the development of this innovative PFD loaded lecithin nanocapsules achieved a targeting ability to the liver, controlled drug release, thereby increase the PFD therapeutic value in downregulating hepatic fibrosis in adjunct with the reduction of liver toxicity.

Polycaprolactone and polycaprolactone triol blends to obtain a stable liquid nanotechnological formulation: synthesis, characterization and in vitro - in vivo taste masking evaluation

The use of polymeric blends is a potential strategy to obtain novel nanotechnological formulations aiming at drug delivery systems. Saquinavir, an antiretroviral drug, was chosen as a model drug for the development of new stable liquid formulations with unpleasant taste masking properties. Three formulations containing different polymeric ratios (1:3, 1:1 and 3:1) were prepared and properly characterized by particle size distribution, zeta potential, pH, drug content and encapsulation efficiency measurements. The stability was verified by monitoring the zeta potential, particle size distribution, polydispersity index and drug content by 90 days. The light backscattering analysis was used to early identify possible phenomena of instability in the formulations. The in vitro drug release and saquinavir cytotoxicity were evaluated. The in vitro and in vivo taste masking properties were studied using an electronic tongue and a human sensory panel. All formulations presented nanometric sizes around 200 nm and encapsulation efficiency above 99%. The parameters evaluated for stability remained constant throughout 90 days. The in vitro tests showed a controlled drug release and absence of toxic effects on human T lymphocytes. The electronic tongue experiment showed taste differences for all formulations in comparison to drug solutions, with a more pronounced difference for the formulation with higher polycaprolactone content (3:1). This formulation was chosen for in vivo sensory panel evaluation which results corroborated the electronic tongue experiments. In conclusion, the polymer blend nanoformulation developed herein showed the promising application to incorporate drugs aiming at pharmaceutical taste-masking properties.

Nanoformulation Shows Cytotoxicity against Glioblastoma Cell Lines and Antiangiogenic Activity in Chicken Chorioallantoic Membrane

Glioblastoma (GB) is a histological and genetically heterogeneous brain tumor that is highly proliferative and vascularized. The prognosis is poor with currently available treatment. In this study, we evaluated the cytotoxicity and antiangiogenic activity of doxorubicin-loaded-chitosan-coated-arginylglycylaspartic acid-functionalized-poly(ε-caprolactone)-alpha bisabolol-LNC (AB-DOX-LNC-L-C-RGD). The nanoformulation was prepared by self-assembling followed by interfacial reactions, physicochemically characterized and evaluated in vitro against GB cell lines (U87MG and U138MG) and in vivo using the chicken chorioallantoic membrane assay (CAM). Spherical shape nanocapsules had a hydrodynamic mean diameter of 138 nm, zeta potential of +13.4 mV, doxorubicin encapsulation of 65%, and RGD conjugation of 92%. After 24 h of treatment (U87MG and U138MG), the median inhibition concentrations (IC₅₀) were 520 and 490 nmol L⁻¹ doxorubicin-equivalent concentrations, respectively. The treatment induced antiproliferative activity with S-phase cell-cycle arrest and apoptosis in the GB cells. Furthermore, after 48 h of exposure, evaluation of antiangiogenic activity (CAM) showed that the relative vessel growth following treatment with the nanocapsules was 5.4 times lower than that with the control treatment. The results support the therapeutic potential of the nanoformulation against GB and, thereby, pave the way for future preclinical studies.

Current approaches in lipid-based nanocarriers for oral drug delivery

Lipid-based nanocarriers have gained much interest as carriers of drugs with poor oral bioavailability because of their remarkable advantages like low toxicity, affordable scale-up manufacture, strong biocompatibility or high drug loading efficiency. The potential of these nanocarriers lies in their ability to improve the gastrointestinal stability, solubility and permeability of their cargo drugs. However, achieving efficient oral drug delivery through lipid-based nanocarriers is a challenging task, since they encounter multiple physicochemical barriers along the gastrointestinal tract, e.g. the gastric acidic content, the intestinal mucus layer or the enzymatic degradation, that they must surmount to reach their target. These limitations may be turned into opportunities through a rational design of lipid-based nanocarriers. For that purpose, this review focuses on the main challenges of the oral route indicating the strategies undertaken for lipid-based nanocarriers in order to overcome them. Understanding their shortcomings and identifying their strengths will determine the future clinical success of lipid-based nanocarriers.

Paliperidone-Loaded Nanolipomer System for Sustained Delivery and Enhanced Intestinal Permeation: Superiority to Polymeric and Solid Lipid Nanoparticles

Paliperidone (PPD) is the most recent second-generation atypical antipsychotic approved for the treatment of schizophrenia. An immediate release dose causes extrapyramidal side effects. In this work, a novel nanolipomer carrier system for PPD with enhanced intestinal permeability and sustained release properties has been developed and optimized. PPD was successfully encapsulated into a lipomer consisting of a specific combination of biocompatible materials including poly-ε-caprolactone as a polymeric core, Lipoid S75, and Gelucire® 50/13 as a lipid shell and polyvinyl alcohol as a stabilizing agent. The lipomer system was characterized by dynamic light scattering, TEM, DSC, and FTIR. An optimized lipomer formulation possessed a particle size of 168 nm, PDI of 0.2, zeta potential of -23 mV and an encapsulation efficiency of 87.27% ± 0.098. Stability in simulated gastrointestinal fluids investigated in terms of particle size, zeta potential, and encapsulation efficiency measurements ensured the integrity of the nanoparticles upon oral administration. PPD-loaded nanolipomers demonstrated a superior sustained release behavior up to 24 h and better ex vivo intestinal permeation for PPD compared to the corresponding polymeric and solid lipid nanoparticles and drug suspension. The in vitro hemocompatibility test on red blood cells revealed no hemolytic effect of PPD-loaded lipomers which reflects its safety. The elaborated nanohybrid carrier system represents a promising candidate for enhancing the absorption of PPD providing a 2.6-fold increase in the intestinal permeation flux compared to the drug suspension while maintaining a sustained release behavior. It is a convenient alternative to the commercially available dosage form of PPD.

Improved photostability and cytotoxic effect of coenzyme Q10 by its association with vitamin E acetate in polymeric nanocapsules

The present study showed the development of nanocapsules containing the association of the coenzyme Q10 and vitamin E acetate and the evaluation of their effect on in vitro cells culture of malignant glioma and melanoma. In order to investigate if nanocapsules are able to protect coenzyme Q10 from degradation under UVC radiation, a photostability study was carried out. For this, three concentrations of vitamin E acetate were evaluated (1%, 2%, or 3%). Nanocapsules presented suitable physicochemical characteristics and were able to protect coenzyme Q10 from photodegradation. In addition, this protection was influenced by higher vitamin E acetate concentrations, attributing to this oil an important role on coenzyme Q10 photostabilization. Regarding to in vitro citotoxicity assay, nanocapsules containing coenzyme Q10 and 2% vitamin E significantly reduced glioma and melanoma cell viability in 61% and 66%, respectively. In this sense, these formulations represent interesting platforms for the delivery of coenzyme Q10 and vitamin E acetate, presenting effect on the reduction of malignant cells viability.

The use of chitosan as cationic coating or gel vehicle for polymeric nanocapsules: Increasing penetration and adhesion of imiquimod in vaginal tissue

The human papillomavirus (HPV) infection, which is strongly related to cervical cancer, can be reduced by the topical application of imiquimod. Some strategies have been used to increase the adhesion and penetration of drugs through the vaginal mucosa. Two of them are the development of mucoadhesive semisolid formulations and the development of polymeric nanocarriers. In this paper, we hypothesize that the combined use of these two strategies results in a better performance of the formulation to retain imiquimod into the vaginal tissue. Aiming this, two different systems are proposed: (a) chitosan-coated poly(ε-caprolactone)-nanocapsules incorporated into hydroxyethylcellulose gel (HEC-NC_imiq-chit), and (b) poly(ε-caprolactone)-nanocapsules incorporated into chitosan hydrogel (CHIT-NC_imiq). These formulations were submitted to three main tests: mucoadhesivity by interaction, permeation and washability test (or retention test). We developed an integrative index that allows comparing the global performance of the proposed formulations by considering jointly the results of these three tests. Thus, when considered the integrative indexes for the formulations, our results show that CHIT-NC_imiq presents the best performance for the treatment of HPV.

In vitro toxicity assessment of oral nanocarriers

The fascinating properties of nanomaterials opened new frontiers in medicine. Nanocarriers are useful systems in transporting drugs to site-specific targets. The unique physico-chemical characteristics making nanocarriers promising devices to treat diseases may also be responsible for potential adverse effects. In order to develop functional nano-based drug delivery systems, efficacy and safety should be carefully evaluated. To date, no common testing strategy to address nanomaterial toxicological challenges has been generated. Different cell culture models are currently used to evaluate nanocarrier safety using conventional in vitro assays, but overall they have generated a huge amount of conflicting data. In this review we describe state-of-the-art approaches for in vitro testing of orally administered nanocarriers, highlighting the importance of developing harmonized and validated standard operating procedures. These procedures should be applied in a safe-by-design context with the aim to reduce and/or eliminate the uncertainties and risks associated with nanomedicine development.

Novel therapeutic mechanisms determine the effectiveness of lipid-core nanocapsules on melanoma models

Melanoma is a severe metastatic skin cancer with poor prognosis and no effective treatment. Therefore, novel therapeutic approaches using nanotechnology have been proposed to improve therapeutic effectiveness. Lipid-core nanocapsules (LNCs), prepared with poly(ε-caprolactone), capric/caprylic triglyceride, and sorbitan monostearate and stabilized by polysorbate 80, are efficient as drug delivery systems. Here, we investigated the effects of acetyleugenol-loaded LNC (AcE-LNC) on human SK-Mel-28 melanoma cells and its therapeutic efficacies on melanoma induced by B16F10 in C57B6 mice. LNC and AcE-LNC had z-average diameters and zeta potential close to 210 nm and -10.0 mV, respectively. CytoViva(®) microscopy images showed that LNC and AcE-LNC penetrated into SK-Mel-28 cells, and remained in the cytoplasm. AcE-LNC in vitro treatment (18-90×10(9) particles/mL; 1 hour) induced late apoptosis and necrosis; LNC and AcE-LNC (3-18×10(9) particles/mL; 48 hours) treatments reduced cell proliferation and delayed the cell cycle. Elevated levels of nitric oxide were found in supernatant of LNC and AcE-LNC, which were not dependent on nitric oxide synthase expressions. Daily intraperitoneal or oral treatment (days 3-10 after tumor injection) with LNC or AcE-LNC (1×10(12) particles/day), but not with AcE (50 mg/kg/day, same dose as AcE-LNC), reduced the volume of the tumor; nevertheless, intraperitoneal treatment caused toxicity. Oral LNC treatment was more efficient than AcE-LNC treatment. Moreover, oral treatment with nonencapsulated capric/caprylic triglyceride did not inhibit tumor development, implying that nanocapsule supramolecular structure is important to the therapeutic effects. Together, data herein presented highlight the relevance of the supramolecular structure of LNCs to toxicity on SK-Mel-28 cells and to the therapeutic efficacy on melanoma development in mice, conferring novel therapeutic mechanisms to LNC further than a drug delivery system.

Transport features and structural optimization of solid lipid nanoparticles crossing the intestinal epithelium

In vitro simulated intestinal epithelial cell monolayer is a novel avenue to screen optimal SLNs formulations.

Do poly(epsilon-caprolactone) lipid-core nanocapsules induce oxidative or inflammatory damage after in vivo subchronic treatment?

Among the toxicity mechanisms linked to nanoparticles (NPs), oxidative stress (OS) and inflammation are, in general, presumed to mediate their toxicological responses.

Dithranol-loaded lipid-core nanocapsules improve the photostability and reduce the in vitro irritation potential of this drug

Dithranol is a very effective drug for the topical treatment of psoriasis. However, it has some adverse effects such as irritation and stain in the skin that make its application and patient adherence to treatment difficult. The aims of this work were to prepare and characterize dithranol-loaded nanocapsules as well as to evaluate the photostability and the irritation potential of these nanocarriers. Lipid-core nanocapsules containing dithranol (0.5 mg/mL) were prepared by interfacial deposition of preformed polymer. EDTA (0.05%) or ascorbic acid (0.02%) was used as antioxidants. After preparation, dithranol-loaded lipid-core nanocapsules showed satisfactory characteristics: drug content close to the theoretical concentration, encapsulation efficiency of about 100%, nanometric mean size (230-250 nm), polydispersity index below 0.25, negative zeta potential, and pH values from 4.3 to 5.6. In the photodegradation study against UVA light, we observed a higher stability of the dithranol-loaded lipid-core nanocapsules comparing to the solution containing the free drug (half-life times around 4 and 1h for the dithranol-loaded lipid-core nanocapsules and free drug solution containing EDTA, respectively; half-life times around 17 and 7h for the dithranol-loaded lipid-core nanocapsules and free drug solution containing ascorbic acid, respectively). Irritation test by HET-CAM method was conducted to evaluate the safety of the formulations. From the results it was found that the nanoencapsulation of the drug decreased its toxicity compared to the effects observed for the free drug.

Intestinal absorption and biological effects of orally administered amorphous silica particles

Although amorphous silica nanoparticles are widely used in the production of food products (e.g., as anticaking agents), there is little information available about their absorption and biological effects after oral exposure. Here, we examined the in vitro intestinal absorption and in vivo biological effects in mice of orally administered amorphous silica particles with diameters of 70, 300, and 1,000 nm (nSP70, mSP300, and mSP1000, respectively) and of nSP70 that had been surface-modified with carboxyl or amine groups (nSP70-C and nSP70-N, respectively). Analysis of intestinal absorption by means of the everted gut sac method combined with an inductively coupled plasma optical emission spectrometer showed that the intestinal absorption of nSP70-C was significantly greater than that of nSP70. The absorption of nSP70-N tended to be greater than that of nSP70; however, the results were not statistically significant. Our results indicate that silica nanoparticles can be absorbed through the intestine and that particle diameter and surface properties are major determinants of the degree of absorption. We also examined the biological effects of the silica particles after 28-day oral exposure in mice. Hematological, histopathological, and biochemical analyses showed no significant differences between control mice and mice treated with the silica particles, suggesting that the silica nanoparticles evaluated in this study are safe for use in food production.

Labeling the oily core of nanocapsules and lipid-core nanocapsules with a triglyceride conjugated to a fluorescent dye as a strategy to particle tracking in biological studies

The synthesis of novel fluorescent materials represents a very important step to obtain labeled nanoformulations in order to evaluate their biological behavior. The strategy of conjugating a fluorescent dye with triacylglycerol allows that either particles differing regarding supramolecular structure, i.e., nanoemulsions, nanocapsules, lipid-core nanocapsules, or surface charge, i.e., cationic nanocapsules and anionic nanocapsules, can be tracked using the same labeled material. In this way, a rhodamine B-conjugated triglyceride was obtained to prepare fluorescent polymeric nanocapsules. Different formulations were obtained, nanocapsules (NC) or lipid-core nanocapsules (LNC), using the labeled oil and Eudragit RS100, Eudragit S100, or poly(caprolactone) (PCL), respectively. The rhodamine B was coupled with the ricinolein by activating the carboxylic function using a carbodiimide derivative. Thin layer chromatography, proton nuclear magnetic resonance ((1)H-NMR), Fourier transform infrared spectroscopy (FTIR), UV-vis, and fluorescence spectroscopy were used to identify the new product. Fluorescent nanocapsule aqueous suspensions were prepared by the solvent displacement method. Their pH values were 4.6 (NC-RS100), 3.5 (NC-S100), and 5.0 (LNC-PCL). The volume-weighted mean diameter (D 4.3) and polydispersity values were 150 nm and 1.05 (NC-RS100), 350 nm and 2.28 (NC-S100), and 270 nm and 1.67 (LNC-PCL). The mean diameters determined by photon correlation spectroscopy (PCS) (z-average) were around 200 nm. The zeta potential values were +5.85 mV (NC-RS100), -21.12 mV (NC-S100), and -19.25 mV (LNC-PCL). The wavelengths of maximum fluorescence emission were 567 nm (NC-RS100 and LNC-PCL) and 574 nm (NC-S100). Fluorescence microscopy was used to evaluate the cell uptake (human macrophage cell line) of the fluorescent nanocapsules in order to show the applicability of the approach. When the cells were treated with the fluorescent nanocapsules, red emission was detected around the cell nucleus. We demonstrated that the rhodamine B-conjugated triglyceride is a promising new material to obtain versatile dye-labeled nanocarriers presenting different chemical nature in their surfaces.

In vivo toxicological evaluation of polymeric nanocapsules after intradermal administration

Polymeric nanocarriers have shown great promise as delivery systems. An alternative strategy has been to explore new delivery routes, such as intradermal (i.d.), that can be used for vaccines and patch-based drug delivery. Despite their many advantages, there are few toxicity studies, especially in vivo. We report a safety assessment of biodegradable poly(ɛ-caprolactone) lipid-core nanocapsules (LNC) with a mean size of 245±10nm following single and repeated intradermal injections to Wistar rats. Suspensions were prepared by interfacial deposition of polymer. The animals (n=6/group) received a single-dose of saline solution (1.2ml/kg) or LNC (7.2×10(12)LNC/kg), or repeated-doses of two controls, saline solution or Tween 80 (0.9ml/kg), or three different concentrations of LNC (1.8, 3.6, and 5.4×10(12)LNC/kg) for 28 consecutive days. Clinical and physiological signs and mortality were observed. Samples of urine, blood, and tissue were used to perform toxicological evaluation. There were no clinical signs of toxicity or mortality, but there was a slight decrease in the relative body weights in the Tween 80-treated group (p<0.01) after repeated administration. No histopathological alterations were observed in tissues or significant changes in blood and urinary biomarkers for tissue damage. Mild alterations in white blood cells count with increases in granulocytes in the Tween-80 group (p<0.05) were found. Genotoxicity was evaluated through the comet assay, and no statistical difference was observed among the groups. Therefore, we conclude that, under the conditions of these experiments, biodegradable LNC did not present appreciable toxicity after 28 consecutive days of intradermal administration and is promising for its future application in vaccines and patch-based devices for enhancing the delivery of drugs.

Nanoparticle toxicity by the gastrointestinal route: evidence and knowledge gaps

The increasing interest in nanoparticles for advanced technologies, consumer products, and biomedical applications has led to great excitement about potential benefits but also concern over the potential for adverse human health effects. The gastrointestinal tract represents a likely route of entry for many nanomaterials, both directly through intentional ingestion or indirectly via nanoparticle dissolution from food containers or by secondary ingestion of inhaled particles. Additionally, increased utilisation of nanoparticles may lead to increased environmental contamination and unintentional ingestion via water, food animals, or fish. The gastrointestinal tract is a site of complex, symbiotic interactions between host cells and the resident microbiome. Accordingly, evaluation of nanoparticles must take into consideration not only absorption and extraintestinal organ accumulation but also the potential for altered gut microbes and the effects of this perturbation on the host. The existing literature was evaluated for evidence of toxicity based on these considerations. Focus was placed on three categories of nanomaterials: nanometals and metal oxides, carbon-based nanoparticles, and polymer/dendrimers with emphasis on those particles of greatest relevance to gastrointestinal exposures.

Sulfobutylether-β-cyclodextrin/chitosan nanoparticles enhance the oral permeability and bioavailability of docetaxel

The aim of this research is to develop novel chitosan nanoparticles including cyclodextrins complexes for docetaxel (DTX), evaluate the performance of nanoparticles which could enhance the oral permeability and bioavailability of DTX in vitro and in vivo. DTX/sulfobutylether-β-cyclodextrin inclusion complexes were made and it was the main ingredient to prepare the DTX/sulfobutylether-β-cyclodextrin/chitosan nanoparticles due to their promising physicochemical properties. DTX/sulfobutylether-β-cyclodextrin/chitosan nanoparticles were prepared by the ionic gelation of chitosan with tripolyphosphate in the presence of cyclodextrins. Results indicated that DTX/sulfobutylether-β-cyclodextrin inclusion complexes and docetaxel/sulfobutylether-β-cyclodextrin/chitosan nanoparticles both had good performances in the studies of release and the rat small intestinal absorption in vitro. DTX/sulfobutylether-β-cyclodextrin/chitosan nanoparticles showed preferable capability in improving the small intestinal absorption and inhibiting the efflux of DTX. In pharmacokinetics study, the DTX/sulfobutylether-β-cyclodextrin/chitosan nanoparticles increased the AUC0→t and decreased the clearance significantly, and the oral relative bioavailability of the DTX/sulfobutylether-β-cyclodextrin/chitosan nanoparticles was as high as 1447.53% compared to the pure DTX formulation. The DTX/sulfobutylether-β-cyclodextrin/chitosan nanoparticles prepared in this study have a good prospect for oral administration as an alternative of current DTX formulations.

Everted gut sac model as a tool in pharmaceutical research: limitations and applications

OBJECTIVES

This review discusses the limitations and applications of the everted gut sac model in studying drug absorption, metabolism, and interaction.

KEY FINDINGS

The mechanism of drug absorption, interaction and the effect of factors such as age, sex, species, chronic therapy, and disease state on drug absorption have been summarized. The experimental conditions and their effects on the outcomes of trials have been discussed also.

SUMMARY

The everted sac model is an efficient tool for studying in-vitro drug absorption mechanisms, intestinal metabolism of drugs, role of transporter in drug absorption, and for investigating the role of intestinal enzymes during drug transport through the intestine.