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In this work, we propose the variable temperature multiple light scattering (VTMLS) as a novel method to determine an enthalpic term of the agglomeration process of submicrometric colloidal systems such as polymeric nanocapsules (NCs) and lipid-core nanocapsules (LNCs). Four different aqueous suspensions were prepared using a linear polyester, triacylglycerol, octyl methoxycinnamate and polysorbate 80 in the presence (individually and combined) or absence of the surfactants: phosphatidylcholine and sorbitan monostearate. Backscattering (BS) signals were monitored applying a temperature gradient from 23 °C to 56 °C (increase of 3 °C at 5-min intervals). Considering the Indefinite Self-Association Model, a relation between the BS signal and the equilibrium constant of the agglomeration process was established. The values of A′ΔH°, obtained by VTMLS for each colloidal aqueous suspension, were predictive of the system physical stability when compared to long-term stability studies. The use of phosphatidylcholine decreased the physical stability of either LNC or NC. The approach enabled to differentiate the first step of the physical destabilization, which corresponds to a reversible surfactant desorption. In conclusion, the new non-destructive analysis can be used to quickly compare the relative physical stability of colloidal systems representing a valuable tool to develop new formulations of dispersed systems.

Lipoic acid (LA) is a water- and lipid-soluble molecule with capacity to pass through cell membranes and with several antioxidant properties. Previous studies have shown that polymeric nanocapsules with LA favor the protection of this antioxidant, increasing their physical and chemical stability compared to formulations containing free LA. The aim of this study was to evaluate and compare the effect of free LA and LA-nanocapsules on antioxidant enzymes, the concentration of reduced glutathione (GSH) and a by-product of lipid peroxidation (malondialdehyde), as well as the expression of gene coding for different forms of glutathione-S-transferase (GST) in model fish. For this, carp Cyprinus carpio (Cyprinidae) were exposed (i.p.) to different forms of LA (free and in nanocapsules) for different times (48 h, 96 h and 1 week) and the brain, liver and muscle were analyzed. Results indicated that the organs respond differently depending on the time and form in which LA was delivered. After 96 h and 1 week, a better antioxidant response was found generally in the formulation with nanocapsules. The nanocapsule composition showed to be a factor to be considered in future studies, because in some organs and exposure times empty nanocapsules promoted an antioxidant effect and in others a pro-oxidant effect.

The development of novel therapeutic strategies to treat gliomas remains critical as a result of the poor prognoses, inef-. ficient therapies and recurrence associated with these tumors. In this context, biodegradable nanoparticles are emerging as efficient drug delivery systems for the treatment of difficult-to-treat diseases such as brain tumors. In the current study, we evaluated the antiglioma effect of trans-resveratrol-loaded lipid-core nanocapsules (RSV-LNC) based on in vitro (C6 glioma cell line) and in vivo (brain-implanted C6 cells) models of the disease. In vitro, RSV-LNC decreased the viability of C6 glioma cells to a higher extent than resveratrol in solution. Interestingly, RSV-LNC treatment was not cytotoxic to hippocampal organotypic cultures, a model of healthy neural cells, suggesting selectivity for cancer cells. RSV-LNC induced losses in glioma cell viability through induction of apoptotic cell death, as assessed by Annexin-FITC/PI assay, which was preceded by an early arrest in the S and G1 phases of the cell cycle. In brain-implanted C6 tumors, treatment with RSV-LNC (5 mg/kg/day, i.p.) for 10 days promoted a marked decrease in tumor size and also reduced the incidence of some malignant tumor-associated characteristics, such as intratumoral hemorrhaging, intratumoral edema and pseudopalisading, compared to resveratrol in solution. Taken together, the results presented herein suggest that nanoencapsulation of resveratrol improves its antiglioma activity, thus providing a provocative foundation for testing the clinical usefulness of nanoformulations of this natural compound as a new chemotherapeutic strategy for the treatment of gliomas.

Poly(ϵ-caprolactone) (PCL), a biodegradable and biocompatible polymer, is useful to encapsulate a wide range of drugs making it an interesting material for the preparation of carriers with potential applications in therapeutics.The design and development of those carriers to modulate drug release, to improve the drug stability or apparent solubility in aqueous media, as well as to target tissues and organs are discussed.Microencapsulation is a well-established process in pharmaceutical industry to protect drugs from chemical degradation and to control drug release. In this context, PCL is a useful polymer to prepare microcapsules. Nanoencapsulation, a more recent approach, offers new possibilities in drug delivery. PCL can be used as polymer to prepare different types of nanocapsules presenting diverse flexibility according to the chemical nature of the core. Those nanocapsules are capable of controlling drug release and improving photochemical stability. In addition, they can modulate cutaneous drug penetration/permeation and act as physical sunscreen due to their capability of light scattering. Considering the pharmaceutical point of view, PCL nanocapsules are versatile formulations, once they can be used in the liquid form, as well as incorporated into semi-solid or solid dosage forms.

In this study, we developed curcumin-loaded lipid-core nanocapsules (C-LNCs) in an attempt to improve the antiglioma activity of this polyphenol. C-LNC showed nanotechnological properties such as nanometric mean size (196 nm), 100% encapsulation efficiency, polydispersity index below 0.1, and negative zeta potential. The in vitro release assays demonstrated a controlled release of curcumin from lipid-core nanocapsules. In C6 and U251MG gliomas, C-LNC promoted a biphasic delivery of curcumin: the first peak occurred early in the treatment (1-3h), whereas the onset of the second phase occurred after 48 h. In C6 cells, the cytotoxicity of C-LNC was comparable to non-encapsulated curcumin only after 96 h, whereas C-LNCs were more cytotoxic than non-encapsulated curcumin after 24h of incubation in U251MG. Induction of G2/M arrest and autophagy were observed in C-LNC as well as in free-curcumin treatments. In rats bearing C6 gliomas, C-LNC (1.5mg/kg/day, i.p.) decreased the tumor size and malignance and prolonged animal survival when compared to same dose of non-encapsulated drug. In addition, serum markers of tissue toxicity and histological parameters were not altered. Considered overall, the data suggest that the nanoencapsulation of curcumin in LNC is an important strategy to improve its pharmacological efficacy in the treatment of gliomas.

Alzheimer's disease (AD), a neurodegenerative disorder exhibiting a gradual decline in cognitive function, is characterized by the presence of neuritic plaques composed of neurofibrillary tangles and amyloid-β (Aβ) peptide. Available drugs for AD therapy have small effect sizes and do not alter disease progression. Several studies have been shown that resveratrol is associated with anti-amyloidogenic properties, but therapeutic application of its beneficial effects is limited. Here we compared the neuroprotective effects of free resveratrol treatment with those of resveratrol-loaded lipid-core nanocapsule treatment against intracerebroventricular injection of Aβ1-42 in rats. Animals received a single intracerebroventricular injection of Aβ1-42 (2 nmol), and 1 day after Aβ infusion, they were administered either free resveratrol (RSV) or resveratrol-loaded lipid-core nanocapsules (5 mg/kg, each 12 h, intraperitoneally), for 14 days. Aβ1-42-infused animals showed a significant impairment on learning memory ability, which was paralleled by a significant decrease in hippocampal synaptophysin levels. Furthermore, animals exhibited activated astrocytes and microglial cells, as well as disturbance in c-Jun N-terminal kinase (JNK) and glycogen synthase kinase-3β (GSK-3β) activation, beyond destabilization of β-catenin levels. Our results clearly show that by using lipid-core nanocapsules, resveratrol was able to rescue the deleterious effects of Aβ1-42 while treatment with RSV presented only partial beneficial effects. These findings might be explained by the robust increase of resveratrol concentration in the brain tissue achieved by lipid-core nanocapsules. Our data not only confirm the potential of resveratrol in treating AD but also offer an effective way to improve the efficiency of resveratrol through the use of nanodrug delivery systems.

In this study, a novel method to determine the cloud point temperature variation in aqueous solutions of thermoresponsive homo- and copolymers was developed. Poly(N-vinylcaprolactam) (PVCL) and triblock copolymers of poly(t-butyl acrylate-co-acrylic acid)-b-poly(N-vinylcaprolactam)-b-(t-butyl acrylate-co-acrylic acid) (P[(tBA-co-AA)-b-PVCL-b-P(tBA-co-AA)] were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and used as models. The incorporation of AA units (hydrophilic segments) into the polymeric chain of PVCL influenced the phase transition, increasing the cloud point temperature of the final copolymer. The cloud point temperatures of the PVCL and the triblock copolymer P(tBA-co-AA)-b-PVCL-b-P(tBA-co-AA) were determined by measuring the transmittance of aqueous solutions of the polymers in a Turbiscan Lab instrument in the range of 29 to 40 C. This is the first study in which Turbiscan Lab is used to determine the cloud point temperature.

Several studies have described the benefits of nanoscience and nanotechnology (N&N) in different sectors such as agriculture, energy, environmental preservation, and public health. The rapid evolution of N&N can be shown through a panoramic analysis of scientific papers and patents. In the area of public health, it is estimated that the global market for nanotechnology products will expand to 160 billion U.S. dollars in 2015. The Brazilian government has also strengthened its innovative potential in N&N through economic subsidies, as observed for other countries. This review is focused on the current landscape of N&N in a therapeutic context, highlighting the development of nanotech-products produced with biocompatible and biodegradable materials that are already commercially available or under investigation. Most studies under investigation are focused on the development of nanotechnology-based formulations intended for treatment of cancer, inflammatory, cardiovascular, and neurological diseases. Although there are several advantages of N&N in healthcare, many challenges have to be conquered to increase the availability of nanotechnology products in toxicological, preclinical and clinical studies, scale-up, regulatory, and private investments.

Even though technologies involving nano/microparticles have great potential, it is crucial to determine possible toxicity of these technological products before extensive use. Fullerenes C60are nanomaterials with unique physicochemical and biological properties that are important for the development of many technological applications. The aim of this study was to evaluate the consequences of nonphotoexcited fullerene C60exposure in brain acetylcholinesterase expression and activity, antioxidant responses, and oxidative damage using adult zebrafish as an animal model. None of the doses tested (7.5, 15, and 30 mg/kg) altered AChE activity, antioxidant responses, and oxidative damage when zebrafish were exposed to nonphotoexcited C60nano/microparticles during 6 and 12 hours. However, adult zebrafish exposed to the 30 mg/kg dose for 24 hours have shown enhanced AChE activity and augmented lipid peroxidation (TBARS assays) in brain. In addition, the up-regulation of brain AChE activity was neither related to the transcriptional control (RT-qPCR analysis) nor to the direct action of nonphotoexcited C60nano/microparticles on the protein (in vitroresults) but probably involved a posttranscriptional or posttranslational modulation of this enzymatic activity. Taken together these findings provided further evidence of toxic effects on brain after C60exposure.

Aqueous solutions of lipid-core nanocapsules are interesting drug delivery systems for passive drug targeting. In this study, we hypothesized that the drug distribution mechanisms in lipid-core nanocapsule formulations could be categorized into six different types. To experimentally determine the type of drug distribution in these formulations, we proposed the use of an algorithm as an innovative strategy. The approach is shown to be a valuable tool to optimize and select formulations intended for drug delivery. The best physico-chemical parameter in terms of predicting the type of distribution was the log D value. In conclusion, the use of the algorithm developed in this study represents a simple and rapid approach through which it was possible to experimentally determine the drug distribution in colloidal formulations for eight drug models.

The influence of the composition and preparation method on the sol-gel transition temperature (Tsol-gel) and rheological response of poloxamer-based formulations was determined. Manual and more complex mechanical stirring were found to provide similar results. In addition, a linear dependence of Tsol-gel on the poloxamer content was observed in the range of concentrations analyzed, and a Poloxamer 407® concentration of 18% was selected. The addition of hyaluronic acid did not lead to significant changes in the Tsol-gel values. In contrast, the addition of microparticles caused a reduction in Tsol-gel without a significant reduction in gel strength, and pseudoplastic characteristics were observed, indicating that a thermoreversible gel was obtained with a rheology suitable for application in the treatment of burn wounds.

Owing to concerns over the effects of the physicochemical properties of nanoparticles and their interaction with biological systems, further investigation is required. We investigated, for the first time, the toxicity of lipid-core nanocapsules (LNCs) containing a polymeric wall of poly(ε-caprolactone) and a coating of polysorbate 80 used as drug delivery devices (~245nm) in Wistar rats after single- and repeated-dose treatments. The suspensions were prepared by interfacial deposition of the polymer and were physicochemically characterized. Toxicological effects were determined after single doses of 18.03, 36.06, and 72.12 × 10(12) LNC/kg and repeated doses of 6.01, 12.02, and 18.03 × 10(12) LNC/kg for 28 days by ip administration. The results for both the treatments showed no mortality or permanent body weight changes during the experiments. A granulomatous foreign body reaction was observed in the liver and spleen of higher dose groups in acute and subchronic treatments. Most of the hepatotoxicity and nephrotoxicity markers were within the reference values and/or were similar to the control group. However, a slight alteration in the hematologic parameters was observed in both the studies. Thus, to verify a possible methodological influence, we performed an in vitro test to confirm such influence. These findings are in agreement with earlier reports regarding no appreciable toxicity of biodegradable polymeric nanoparticles, indicating that LNC might be a safe candidate for drug delivery system. Furthermore, the results presented in this study are important for health risk assessment and to implement strategies for testing biodegradable polymeric nanoparticles.

In this study, chia seed oil was nanoencapsulated utilizing chia seed mucilage (CSM) as wall material. The viscosity, encapsulation efficiency, loading capacity, transmission electron microscopy, FT-IR spectroscopy and thermal properties of chia seed oil nanoparticles (CSO-NP) were performed after preparation. Particle size, zeta potential, span value, and pH of CSO-NP and oxidation stability of nanoencapsulated and unencapsulated oil were evaluated during 28 days of storage at accelerated conditions (40 °C). The CSO-NP showed spherical shape, an average size of 205 ± 4.24 nm and zeta potential of −11.58 ± 1.87 mV. The encapsulation efficiency (82.8%), loading capacity (35.38%) and FT-IR spectroscopy demonstrated the interaction between oil and mucilage. Furthermore, CSO-NP were thermally stable at temperatures up 300 °C and nanoencapsulated oil showed higher stability against oxidation than unencapsulated oil. The results suggest that chia seed mucilage represents a promising alternative to substitute synthetic polymers in nanoencapsulation.

Background In vitro evaluation of toxicity and/or efficacy of nanostructured drug delivery systems involves the uses of different controls, including positive and negative controls, as well as a solution or dispersion of the drug in water. One of the most frequently solvent used to dilute poorly water soluble drugs to in vitro tests are dimethylsulfoxide (DMSO). However, its different specific surface area and different diffusion coefficients could make the comparative effects difficult. We proposed that a solvent-free dispersions having similar specific surface area could be a better control than drug in solution against cell lines. Methods We evaluate the effect of curcumin-loaded lipid-core nanocapsules, curcumin-loaded nanoemulsion and curcumin DMSO-water solution on viability and colony forming efficiency of human breast cancer cell line, MCF7. Results The cytotoxic effect of nanocapsules at 24–72 h was similar to nanoemulsion and lower than drug solution. However, the nanocapsules had a superior anticancer activity when long periods (10 days) were evaluated, which highlight the sustained drug release by nanocapsules. Conclusions Our results showed a superior anticancer activity of curcumin-loaded lipid-core nanocapsules compared to curcumin-loaded nanoemulsion and curcumin dissolved in DMSO in long exposition time assay, wihch is not observed in short exposition time assays like MTT. When a poorly water-soluble drug is under investigation, the nanoemulsion prepared with the same compounds of the nanocapsules, except the polymer, could be a better control than DMSO-solution of drug.

To analyze the anti-inflammatory and analgesic effects of an adhesive resin containing indomethacin-loaded nanocapsules in rat model.Adhesive resin disks with or without indomethacin-loaded nanocapsules were subcutaneously implanted into right hind paw of rats. A week after surgical procedure, 2% formalin solution was intradermally injected into plantar surface of paw. Nociceptive and inflammatory responses were evaluated by formalin test. Paw edema by pletismometer and mechanical hyperalgesia by von Frey test were performed on day 2, day 4, day 6, day 8, day 10 and day 12 after surgery. IL-6, IL-10, and lactate dehydrogenase (LDH) serum levels were determined by ELISA-sandwich test.Group containing indomethacin-loaded nanocapsules (NC) presented lower edema in the right hind paw at 24h after formalin injection than those of the control group (CT) (P0.01). NC group showed decrease in the nociceptive response in phase I (neurogenic pain) compared to CT group (NC - 66.86±22.83s X CT - 130.17±35.83s, P0.001). NC group presented supporting higher intensity of stimulus on days 8 and 12 (24h and 72h after formalin injection) (P0.01 and P0.02 respectively). The IL-6 serum level was also significantly higher in the NC group than CT group (p0.001).These results indicate that an adhesive resin containing indomethacin-loaded nanocapsules has anti-inflammatory and nociceptive activities in a chemical model of acute inflammation. The present investigation confirms an adhesive resin with drug-loaded nanocapsules may be useful for improving therapeutic effect for adhesives to be used in deep cavities.

An innovative nanocapsule formulation for parenteral administration using selected vegetable oils (mango, jojoba, pequi, oat, annatto, calendula, and chamomile) was developed that has the potential to encapsulate various drugs. The vegetable oil-loaded nanocapsules were prepared by interfacial deposition and compared with capric/caprylic triglyceride-loaded lipid core nanocapsules. The major objective was to investigate the effect of vegetable oils on particle size distribution and physical stability and to determine the hemolytic potential of the nanocapsules, considering their applicability for intravenous administration. Taking into account the importance of accurately determining particle size for the selected route of administration, different size characterization techniques were employed, such as Laser Diffraction, Dynamic Light Scattering, Multiple Light Scattering, Nanoparticle Tracking Analysis, and Transmission Electronic Microscopy. Laser diffraction studies indicated that the mean particle size of all nanocapsules was below 300 nm. For smaller particles, the laser diffraction and multiple light scattering data were in agreement (D[3,2]-130 nm). Dynamic light scattering and nanoparticle tracking analysis, two powerful techniques that complement each other, exhibited size values between 180 and 259 nm for all nanoparticles. Stability studies demonstrated a tendency of particle creaming for jojoba-nanocapsules and sedimentation for the other nanoparticles; however, no size variation occurred over 30 days. The hemolysis test proved the hemocompatibility of all nanosystems, irrespective of the type of oil. Although all developed nanocapsules presented the potential for parenteral administration, jojoba oil-loaded nanocapsules were selected as the most promising nanoformulation due to their low average size and high particle size homogeneity.

Lipid-core nanocapsules (LNC) are formed by an organogel surrounded by poly(epsilon-caprolactone) and stabilized by polysorbate 80. LNCs increase the concentration of drugs in the brain after oral or intravenous administration. We proposed to determine whether the drug is released from the LNC to cross the blood brain barrier (BBB) or the drug-loaded LNCs can cross the BBB to release the drug. We synthesized a Rhodamine B-polymer conjugate to prepare a fluorescent-labeled LNC formulation, and intravital microscopy was used to determine the ability of the LNCs to cross the brain barrier using different administration routes in C57BI/6 mice. A glioblastoma model was used to determine the impact of the LNC as a shuttle for treatment. After pial vessel exposure, intense fluorescence was detected inside the vessels 10 min after intravenous or 20 min after intraperitoneal injections of fluorescent-labeled LNC. The fluorescence was observed in the perivascular tissue after 30 and 60 min, respectively. Increased tissue fluorescence was detected 240 min after oral administration. The integrity of the barrier was determined during the experiments. Normal leukocyte and platelet adhesion to the vessel wall indicated that Rhodamine B-labeled LNC did not cause pial vessel alterations. After intravenous or oral administration, Rhodamine B-labeled LNC-containing co-encapsulated indomethacin and indomethacin ethyl ester exhibited similar behavior in pial vessels, being more efficient in the treatment of mice with glioblastoma than indomethacin in solution. Therefore, we demonstrated that LNCs act as drug shuttles through the BBB, delivering drugs in brain tissue with high efficiency and reducing glioblastoma after intravenous or oral administration.

There are a range of products available which claim to accelerate the healing of burns; these include topical agents, interactive dressings and biomembranes. The aim of this study was to assess the effect of a gelatin-based membrane containing usnic acid/liposomes on the healing of burns in comparison to silver sulfadiazine ointment and duoDerme® dressing, as well as examining its quantification by high performance liquid chromatography. The quantification of the usnic acid/liposomes was examined using high performance liquid chromatography (HPLC) by performing separate in vitro studies of the efficiency of the biomembranes in terms of encapsulation, drug release and transdermal absorption. Then, second-degree 5cm2 burn wounds were created on the dorsum of nine male pigs, assigned into three groups (n=3): SDZ - animals treated with silver sulfadiazine ointment; GDU - animals treated with duoDerme®; UAL - animals treated with a gelatin-based membrane containing usnic acid/liposomes. These groups were treated for 8, 18 and 30days. In the average rate of contraction, there was no difference among the groups (p>0.05). The results of the quantification showed that biomembranes containing usnic acid/liposomes were controlled released systems capable of transdermal absorption by skin layers. A macroscopic assay did not observe any clinical signs of secondary infections. Microscopy after 8days showed hydropic degeneration of the epithelium, with intense neutrophilic infiltration in all three groups. At 18days, although epidermal neo-formation was only partial in all three groups, it was most incipient in the SDZ group. Granulation tissue was more exuberant and cellularized in the UAL and GDU groups. At 30days, observed restricted granulation tissue in the region below the epithelium in the GDU and UAL groups was observed. In the analysis of collagen though picrosirius, the UAL group showed greater collagen density. Therefore, the UAL group displayed development and maturation of granulation tissue and scar repair that was comparable to that produced by duoDerme®, and better than that produced by treatment with sulfadiazine silver ointment In addition, the UAL group showed increased collagen deposition compared to the other two groups.

The presence of an efficient physical barrier-stratum corneum, the outermost layer of the epidermis-impairs the optimal permeationand penetration of a substance across the skin. Many strategies arebeing researched to improve the delivery of substances to the viablelayers of the epidermis as well as the dermis and blood circulation,after topical administration. This chapter reviews the skin structureand its possible pathways for penetration and permeation, as wellas the most relevant alternatives regarding chemical and physicalmethods to modify drug transport across the skin, with a focus onthe role of composite nanoparticles based on lipids and/or polymersin this process. To comprehend and validate experimental research,a brief review about the available in vitro and in vivo methods to determine drug transport across skin is also included.

Carine C Drewes,1,* Luana A Fiel,2,* Celina G Bexiga,1 Ana Carolina C Asbahr,3 Mayara K Uchiyama,4 Bruno Cogliati,5 Koiti Araki,4 Sílvia S Guterres,2,3 Adriana R Pohlmann,2,3,6 Sandra P Farsky1 1Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, 2Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Sul, Porto Alegre, 3Postgraduate Program in Pharmaceutical Nanotechnology, Federal University of Rio Grande do Sul, Porto Alegre, 4Department of Fundamental Chemistry, Institute of Chemistry, 5Department of Pathology, Faculty of Veterinary Medicine, University of São Paulo, São Paulo, 6Department of Organic Chemistry, Institute of Chemistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil *These authors contributed equally to this work Abstract: 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 210nm and -10.0mV, 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 (18–90×109 particles/mL; 1hour) induced late apoptosis and necrosis; LNC and AcE-LNC (3–18×109 particles/mL; 48hours) 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 (1×1012 particles/day), but not with AcE (50mg/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. Keywords: capric/caprylic triglycerides, mice, acetyleugenol, B16F10 cells, SK-Mel-28, nitric oxide, cell proliferation, nanotoxicology

Achieving oral peptide delivery is an elusive challenge. Emulsion-based minispheres of salmon calcitonin (sCT) were synthesized using single multiple pill (SmPill®) technology incorporating the permeation enhancers (PEs): sodium taurodeoxycholate (NaTDC), sodium caprate (C10), or coco-glucoside (CG), or the pH acidifier, citric acid (CA). Minispheres were coated with an outer layer of Eudragit® L30 D-55 (designed for jejunal release) or Surelease®/Pectin (designed for colonic release). The process was mild and in vitro biological activity of sCT was retained upon release from minispheres stored up to 4 months. In vitro release profiles suggested that sCT was released from minispheres by diffusion through coatings due to swelling of gelatin and the polymeric matrix upon contact with PBS at pH 6.8. X-ray analysis confirmed that coated minispheres dissolved at the intended intestinal region of rats following oral gavage. Uncoated minispheres at a dose of ~ 2000 I.U. sCT/kg were administered to rats by intra-jejunal (i.j.) or intra-colonic (i.c.) instillation and caused hypocalcaemia. Notable sCT absolute bioavailability (F) values were: 5.5% from minispheres containing NaTDC (i.j), 17.3% with CG (i.c.) and 18.2% with C10 (i.c.). Coated minispheres administered by oral gavage at threefold higher doses also induced hypocalcaemia. A highly competitive F value of 2.7% was obtained for orally-administered sCT-minispheres containing CG (45 μmol/kg) and coated with Eudragit®. In conclusion, the SmPill® technology is a potential dosage form for several peptides when formulated with PEs and coated for regional delivery. PK data from instillations over-estimates oral bioavailability and poorly predicts rank ordering of formulations. Science Foundation Ireland

Lipid-core nanocapsules (LCNs) have been proposed as drug carriers to improve brain delivery by modulating drug pharmacokinetics (PK). However, it is not clear whether the LCNs carry the drug through the blood-brain barrier or increase free drug penetration due to changes in the barrier permeability. Quetiapine (QTP) penetration to the brain is mediated by influx transporters and therefore might be reduced by drug transporters inhibitiors as probenecid. The goal of this work was to investigate the role of type-III LCNs on brain penetration of QTP using microdialysis in the presence probenecid. QTP-loaded LCN (QLNC) was successfully obtained with a small particle size (143 ± 6 nm), low polydispersity index (PI0.1), and high encapsulation efficiency (95.4 ± 1.82%.). Total and free drug concentration in plasma and free drug concentration in brain were analyzed following i.v. bolus dosing of nonencapsulated drug (FQ) and QLNC formulations alone and in association with probenecid to male Wistar rats. QTP free plasma fraction right after administration of QLNC was smaller than the fraction observed after FQ dosing; however, it increased over time until similar free drug levels were attained, suggesting that type-III LNCs produce a short in vivo sustained release of the drug. The inhibition of influx transporters by PB led to a reduction of free QTP brain penetration, as observed by the reduction of penetration factor from 1.55 ± 0.17 to a value closer to unit (0.94 ± 0.15). However, when the drug was nanoencapsulated, the inhibition of influx transporters had no effect on the brain penetration factor (0.88 ± 0.21 to 0.92 ± 0.13) probably because QTP is loaded into LNC and not available to interact with transporters. Taken together, these results suggest that LNC type-III carried QTP in the bloodstream and delivered the drug to the brain.

Atherosclerosis is a chronic inflammatory disease responsible for the majority of cases of myocardial infarction and ischemic stroke. The electronegative low-density lipoprotein, a modified subfraction of native LDL, is pro-inflammatory and plays an important role in atherogenesis. To investigate the effects of a nanoformulation (scFv anti-LDL(-)-MCMN-Zn) containing a scFv reactive to LDL(-) on the inhibition of atherosclerosis, its toxicity was evaluated in vitro and in vivo and further it was also administered weekly to LDL receptor knockout mice. The scFv anti-LDL(-)-MCMN-Zn nanoformulation did not induce cell death in RAW 264.7 macrophages and HUVECs. The 5mg/kg dose of scFv anti-LDL(-)-MCMN-Zn did not cause any typical signs of toxicity and it was chosen for the evaluation of its atheroprotective effect in Ldlr(-/-) mice. This nanoformulation significantly decreased the atherosclerotic lesion area at the aortic sinus, compared with that in untreated mice. In addition, the Il1b mRNA expression and CD14 protein expression were downregulated in the atherosclerotic lesions at the aortic arch of Ldlr(-/-) mice treated with scFv anti-LDL(-)-MCMN-Zn. Thus, the scFv anti-LDL(-)-MCMN-Zn nanoformulation inhibited the progression of atherosclerotic lesions, indicating its potential use in a future therapeutic strategy for atherosclerosis.

In this work, a promising approach to increase the advantageous properties of melatonin through its encapsulation into lipid-core nanocapsules (LNC) was examined. Oocytes were treated during in vitro maturation with non-encapsulated melatonin (Mel), melatonin-loaded lipid-core nanocapsules (Mel-LNC), and unloaded LNC. Cytotoxicity, meiotic maturation rate, development to the blastocyst stage, reactive oxygen species (ROS) and glutathione levels, mean cell number and apoptotic cell/blastocyst, and mRNA quantification were evaluated. Both Mel and Mel-LNC enhanced in vitro embryo production, however, Mel-LNC proved to be more effective at decreasing ROS levels and the apoptotic cell number/blastocyst, increasing the cleavage and blastocyst rates, up-regulating the GPX1 and SOD2 genes, and down-regulating the CASP3 and BAX genes. Mel-LNC could penetrate into oocytes and remain inside the cells until they reach the blastocyst stage. In conclusion, when melatonin was encapsulated in LNC and applied during in vitro oocyte maturation, some quality aspects of the blastocysts were improved.

Melatonin has been used as a supplement in culture medium to improve the efficiency of in vitro produced mammalian embryos. Through its ability to scavenge toxic oxygen derivatives and regulate cellular mRNA levels for antioxidant enzymes, this molecule has been shown to play a protective role against damage by free radicals, to which in vitro cultured embryos are exposed during early development. In vivo and in vitro studies have been performed showing that the use of nanocapsules as active substances carriers increases stability, bioavailability and biodistribution of drugs, such as melatonin, to the cells and tissues, improving their antioxidant properties. These properties can be modulated through the manipulation of formula composition, especially in relation to the supramolecular structures of the nanocapsule core and the surface area that greatly influences drug release mechanisms in biological environments. This study aimed to evaluate the effects of two types of melatonin-loaded nanocapsules with distinct supramolecular structures, polymeric (NC) and lipid-core (LNC) nanocapsules, on in vitro cultured bovine embryos. Embryonic development, apoptosis, reactive oxygen species (ROS) production, and mRNA levels of genes involved in cell apoptosis, ROS and cell pluripotency were evaluated after supplementation of culture medium with non-encapsulated melatonin (Mel), melatonin-loaded polymeric nanocapsules (Mel-NC) and melatonin-loaded lipid-core nanocapsules (Mel-LNC) at 10−6, 10−9, and 10−12 M drug concentrations. The highest hatching rate was observed in embryos treated with 10−9 M Mel-LNC. When compared to Mel and Mel-NC treatments at the same concentration (10−9 M), Mel-LNC increased embryo cell number, decreased cell apoptosis and ROS levels, down-regulated mRNA levels of BAX, CASP3, and SHC1 genes, and up-regulated mRNA levels of CAT and SOD2 genes. These findings indicate that nanoencapsulation with LNC increases the protective effects of melatonin against oxidative stress and cell apoptosis during in vitro embryo culture in bovine species.

Polymeric nanocapsules represent an interesting carrier system for cutaneous applications. The possibilities of modulating skin penetration/permeation by altering the design of the formulation and the range of applicability are the main subjects under study. With this in mind, this chapter will address methods of nanocapsule preparation and the influence of the polymeric wall, the surface functionalization, and the vehicle on the skin penetration/permeation profile of active substances loaded in polymeric nanocapsules. Additionally, therapeutic and cosmetic applications of nanocapsules will also be discussed.

Isoflurane is a halogenated ether which is used for general anesthesia. To stabilize a new formulation in order to evaluate the potential to reduce the dose required for general anesthesia, an isoflurane-loaded nanoemulsion was proposed. A high-pressure homogenization technique was used to develop drug-loaded nanoemulsions which presented droplet size of 150 +/- 0.78 nm with a narrow size distribution and low polydispersity index (0.08 +/- 0.01). The zeta potential was -18 +/- 2.4 mV and pH was 6.03 +/- 0.04. Rheological analysis showed Newtonian behavior for the formulations, whose physical stability was confirmed by multiple light scattering. It was verified that isoflurane volatilization did not occur in these formulations. The preclinical evaluation, carried out via the end-tidal isoflurane concentration, showed that the dose required for anesthetic maintenance significantly decreased when the nanostructured formulation was administered compared to inhaled isoflurane. There was no significant difference (p < 0.05) between experimental groups (inhaled isoflurane and intravenous isoflurane-loaded nanoemulsion) in terms of the cardiac rate, oxygen hemoglobin saturation, and arterial blood pressure, as well as the biomarkers of renal, hepatic and skeletal muscle system functionalities. Slight tachypnea, edema, and erythema were observed after isoflurane-loaded or unloaded-nanoemulsion. The stability and significant dose reduction observed for drug-loaded nanoemulsion render this formulation a promising option for intravenous delivery of isoflurane.

Nanocapsules containing poly( d , l -lactide) shell and retinyl palmitate core have been prepared by the pre-formed polymer interfacial deposition method. Dynamic light scattering measurements yielded an average hydrodynamic diameter of ∼220 nm and a polydispersity index of ∼0.12. Small-angle neutron scattering experiments revealed the presence of two populations of nanocapsules of core diameters ∼192 and 65 nm. Freeze fracture transmission electron microscopy showed a polydisperse population of nanocapsules (NC), with a poly( d , l -lactide) shell thickness between 11 and 3 nm. For comparison purposes, nanoemulsions (NE, no polymer) and nanospheres (NS, polymer matrix) were also prepared. Each type of nanoparticles exhibited a different morphology (when examined by electron microscopy), in particular NC showed deformability by capillary adhesion. All three types of nanoparticles successfully encapsulated the poorly water-soluble molecules baicalein and benzophenone-3. The thermal behavior of the various nanoparticles was different to a physical mixture of its individual components. Cytotoxicity and phototoxicity assays, performed in human keratinocytes (HaCaT) and murine fibroblasts (BALB/c 3T3), showed that the NC were only cytotoxic at high concentrations. In vitro release studies of benzophenone-3, by the dialysis bag method using NC and NS, showed a sustained release; however, permeation studies using plastic surgery human abdominal skin in Franz diffusion cells showed that a higher amount of benzophenone-3 from NC penetrated into the skin, most probably due to the deformable nature of these nanoparticles.

Polymeric nanoparticles have been the focus of several researches in the last three decades in diverse areas including the delivery of pharmaceutical, diagnostic and cosmetic agents. These nanocarriers are able to improve the bioavailability and intrinsic solubility of drugs, to target different agents to a specific location or to protect the agent against extrinsic factors, such as radiation and extreme pH conditions. Despite the high interest in the development of these formulations, they hold some disadvantages like the limited physicochemical stability, which hinders the scaling-up of the preparation methods. In this context, spray-drying techniques have been proposed to obtain powder compositions containing polymeric nanoparticles allowing this limited property to be circumvented. In this context, this review is focused on the latest patents related to obtaining spray-dried polymeric nanoparticles, which have been divided into three different groups, according to their approach: i) spray-drying solutions to obtain nanoparticles, ii) spray-drying emulsions/ dispersions to obtain nanoparticles, and iii) nanoparticles dried by spray-drying.

Background The incorporation of substances in nanocarriers can modulate and/or manage their delivery profiles (immediate or sustained) and permeation through skin. Consequently, drug nanencapsulation intended for topical treatment can reduce the systemic absorption of the substance. Objective To obtain and characterize vitamin K1–loaded lipid core nanocapsules as well as to determine whether the nanoencapsulation influences the skin permeation of this vitamin. Methods The skin permeation study was performed by means of Franz-type diffusion cells followed by the tape stripping and retention techniques. The vitamin K1–loaded lipid core nanocapsules were obtained by the preformed polymer precipitation method and the particles were characterized. Results The nanocapsules presented average diameter of 211 ± 2 nm, pH of 5.7 ± 0.3, zeta potential of –14.9 ± 0.6 mV and drug content of 10.2 mg/mL (102.1%). The physical stability of the nanocapsule suspension was verified using multiple light backscattering analysis. The amount of vitamin K1 in the dermis after 8 h of drug permeation was higher when the nanocapsules were applied compared to the control. Moreover, retention in the outermost skin layer and a decrease in the skin permeation to the receptor compartment due to the nanoencapsulation were observed. Conclusion Thus, nanoencapsulation can lead to the selective permeation of vitamin K1 through the skin.

Vegetable oils might be alternatives to mineral or synthetic oils used in nanostructured systems for cutaneous application, due to their advantages with regard to skin care and protection. In this study, we propose the use of vegetable oils (Brazil nut, sunflower seed, olive, rose hip, grape seed and carrot oils) as oily core of Eudragit RS100® nanocapsules and determine their influence on the physicochemical properties of those nanoparticles, in comparison with nanocapsules with capric/caprylic triglycerides as oily core. The formulations containing vegetable oils as core presented pH values suitable for topical application, average diameter close to 280 nm (SPAN around 2.5) and zeta potential close to +7 mV, due to the cationic properties of the polymer. Their viscosities were not affected by the type of oil used as core. By means of multiple light scattering, a reversible particle creaming phenomenon was observed for all the formulations. The nanocapsules prepared using Brazil nut, sunflower seed, oliv...

DEVELOPMENT AND CHARACTERIZATION OF LIPID NANOPARTICLES FOR DAPSONE TOPICAL APPLICATION. In this work, theospheres (innovative lipid nanoparticles) were prepared by the high pressure homogenization technique using different surfactants for dapsone encapsulation. Mean particle size ranged from 105 to 153 nm and negative zeta potentials were obtained for all theosphere formulations. Atomic force microscopy images confirmed the spherical shape of theospheres. The HPLC method used to determine dapsone-loaded theospheres was selective, linear, exact and precise. The entrapment efficiency of dapsone was 91.4%. Theospheres provided controlled release of idebenone (52.7 ± 1.6%) in comparison to the free drug (103.1 ± 1.9%).

A reliable method using LC-UV to assay mometasone furoate (MF) in creams or nasal sprays using the same chromatographic conditions was set up. Methanol:water 80:20 (v/v) (1.0 mL min-1) was used as mobile phase. MF was detected at 248 nm and analyzed in a concentration range from 1.0 to 20.0 µg mL-1. The method provided acceptable theoretical plates, peak simmetry, peak tailing factor and peak resolution a short run (5 min). The method showed specificity, good linearity (r = 0.9999) and the quantification limit was 0.379 µg mL-1. Furthermore, the method was precise (RSD < 2.0%), accurate (recovery > 97%) and robust.

The aims of this work were to increase the photostability and to reduce the skin permeation of tretinoin through nanoencapsulation. Tretinoin is widely used in the topical treatment of various dermatological diseases such as acne, psoriasis, skin cancer, and photoaging. Tretinoin-loaded lipid-core polymeric nanocapsules were prepared by interfacial deposition of a preformed polymer. Carbopol hydrogels containing nanoencapsulated tretinoin presented a pH value of 6.08±0.14, a drug content of 0.52±0.01 mg g(-1), pseudoplastic rheological behavior, and higher spreadability than a marketed formulation. Hydrogels containing nanoencapsulated tretinoin demonstrated a lower photodegradation (24.17±3.49%) than the formulation containing the non-encapsulated drug (68.64±2.92%) after 8h of ultraviolet A irradiation. The half-life of the former was seven times higher than the latter. There was a decrease in the skin permeability coefficient of the drug by nanoencapsulation, independently of the dosage form. The liquid suspension and the semisolid form provided K(p)=0.31±0.15 and K(p)=0.33±0.01 cm s(-1), respectively (p≤0.05), while the samples containing non-encapsulated tretinoin showed K(p)=1.80±0.27 and K(p)=0.73±0.12 cm s(-1) for tretinoin solution and hydrogel, respectively. Lag time was increased two times by nanoencapsulation, meaning that the drug is retained for a longer time on the skin surface.

Lipoic acid is a widely studied substance, whose therapeutic effects are related to its antioxidant activity. Our objective was to develop lipoic acid-loaded lipid-core nanocapsules and evaluate their in vitro antioxidant effect against lipid peroxidation induced by ascorbyl free radicals, using soybean lecithin liposomes as the substrate. The nanocapsule suspensions were prepared by interfacial deposition of poly(epsilon-caprolactone) and characterized by particle size and polydispersion index (photon correlation spectroscopy), zeta potencial (eletrophoretic mobility), drug content and encapsulation efficiency (HPLC). The extent of lipid peroxidation was determined (TBARS). The nanostrucutures presented mean diameters of between 191 and 349 nm, zeta potential values from -14.1 +/- 4.5 to -10.4 +/- 0.6, and high lipoic acid encapsulation. A significant increase in the antioxidant activity of lipoic acid was achieved through nanoencapsulation or by increasing its concentration in the formulation. The protection results ranged from 48.9 +/- 3.4 to 57.4 +/- 9.1% for lipoic acid-loaded lipid-core nanocapsules. The lipoic acid release from nanostrucutures significantly decreased with increasing polymer concentration. Also, it was observed an increasing in the antioxidant activity as the lipoic acid release time decreased. The co-encapsulation of lipoic acid with melatonin in lipid-core nanocapsules did not improve the protection against lipid peroxidation. The results obtained demonstrate the optimal concentrations of polymer and lipoic acid in the formulations in terms of enhancing the antioxidant activity. Furthermore, by the strategy applied, it was verified that nanoencapsulation is an efficient alternative to increase the antioxidant effect of lipoic acid, representing a potential approach for therapeutic applications.

The nanoencapsulation of capsaicinoids (capsaicin and dihydrocapsaicin) was proposed in this work as a strategy to control their release due to the reservoir characteristics of the nanocapsules. This reservoir property could prolong the topical analgesic effect and reduce the burning sensation and skin irritation caused by the capsaicinoids. The nanocapsules were physicochemically characterized and presented z-average diameter of 153 +/- 7 (PDI < 0.2) and zeta potential of +9.62 +/- 1.48 mV. The pH of the aqueous nanoparticle suspension was 5.72 +/- 0.10, which is suitable for cutaneous application. The total capsaicinoids content was 0.5 mg mL(-1) (64% of capsaicin and 33% of dihydrocapsaicin) and their encapsulation efficiencies were close to 100%. The formulation was stable over 90 days. The in vitro release profiles demonstrated that the release of capsaicin and dihydrocapsaicin was prolonged by means of nanoencapsulation. Moreover, comparing the half-life values, it was observed that the polymeric wall significantly affected the release rates for both capsaicinoids. According to Fick's first law, capsaicin presented higher flux (5.6 +/- 0.1 (x10(-4)) mg cm(-2) h(-1)) than that of dihydrocapsaicin (2.1 +/- 0.2 (x 10(-4)) mg cm(-2) h(-1)), which was probably related to its higher gradient concentration. Drug diffusion and polymer relaxation were responsible for the capsaicinoids release from the nanocapsules, which fitted the monoexponential mathematical model. This innovative formulation was designed considering its potential action of prolonging the analgesic effect of the capsaicionoids on the skin.

Polymeric nanoparticle aqueous suspensions have been proposed as drug carriers to improve the efficacy of medicines. Considering those nanocarriers, nanocapsules are vesicular structures containing an oil core surrounded by a polymeric wall. Recently, we proposed the supramolecular model for a new kind of nanocapsule prepared with triacylglycerol, sorbitan monostearate (SM), polyester and polysorbate 80. Varying the proportions of the raw materials in the organic phase, different kinds of colloids could be obtained. So, our objective was to formulate exclusively lipid-core nanocapsules (LNC) in aqueous suspensions. In this way, the analytical approach to verify the quality of the different formulations was based on light scattering measurements (dynamic light scattering, multiple light scattering and laser diffractometry) and density gradient. The increase in the SM concentration showed a slight tendency of both sedimentation and creaming, while the increase in the oil concentration resulted in creaming. For the latter, size distribution as function of time indicated the presence of nanoemulsion simultaneously with LNC. Finally, density gradient showed an exclusive band for formulations prepared using 1:4.1:2.6 (w/w) of SM, medium chain triacylglycerol and polyester, respectively.

The goal of this study was to evaluate the feasibility of preparing nanocapsules and nanoemulsions using tea tree oil as oily phase aiming to protect its volatilization. The nanostructures presented nanometric mean size (160-220 nm) with a polydispersity index below 0.25 and negative zeta potential. The pH values were 6.43 ± 0.37 and 5.98 ± 0.00 for nanoemulsions and nanocapsules, respectively. The oil content after preparation was 96%. The inclusion of tea tree oil in nanocapsules showed higher protection against volatilization. The analysis of mean size and polydispersity index of formulations presented no significant alteration during the storage time.

Several studies have reported that orally ingested trans-resveratrol is extensively metabolized in the enterocyte before it enters the blood and target organs. Additionally, trans-resveratrol is photosensitive, easily oxidized and presents unfavorable pharmacokinetics. Therefore, it is of great interest to stabilize trans-resveratrol in order to preserve its biological activities and to improve its bioavailability in the brain. Here, trans-resveratrol was loaded into lipid-core nanocapsules and analyzed for particle size, polydispersity and zeta potential. The nanocapsule distribution in brain tissue was evaluated by intraperitoneal (i.p.) and gavage routes in healthy rats. The lipid-core nanocapsules had a mean diameter of 241 nm, a polydispersity index of 0.2, and a zeta potential of -15 mV. No physical changes were observed after 1, 2 and 3 months of storage at 25 degrees C. Lipid-core nanocapsules showed high entrapment of trans-resveratrol and displayed a higher trans-resveratrol concentration in the brain, the liver and the kidney after daily i.p. or gavage administration than that observed for the free trans-resveratrol. Because trans-resveratrol is a potent cyclooxygenase-1 inhibitor, gastrointestinal damage was evaluated. The animals that were administered with trans-resveratrol-loaded lipid-core nanocapsules showed significantly less damage when compared to those administered with free trans-resveratrol. In summary, lipid-core nanocapsules exhibited great trans-resveratrol encapsulation efficiency. trans-Resveratrol-loaded lipid-core nanocapsules increased the concentration of trans-resveratrol in the brain tissue. Gastrointestinal safety was improved when compared with free trans-resveratrol. Thus, trans-resveratrol-loaded lipid-core nanocapsules may be used as an alternative potential therapeutic for several diseases including Alzheimer's disease.

The aim of the present work was to develop and characterize a chitosan hydrogel containing capsaicinoids-loaded nanocapsules intended for topical delivery. Such system is promising since it brings ...

Targeted treatment of diseases of the central nervous system remains problematic due to the complex pathogenesis of these disorders and the difficulty in drug delivery. Here we investigate the neuroprotective effect of indomethacin-loaded nanocapsules (IndOH-NC) in an in vitro model of ischemia. For this purpose we used organotypic hippocampal cultures exposed to oxygen-glucose deprivation (OGD). When the cultures were exposed to 60 min of OGD, 54.5±14.7% of the total area of the hippocampal slices was labeled with propidium iodide. On the other hand, when the cultures were treated with 50 or 100 μM of IndOH-NC the cell death was significantly reduced to 31±7% (P

A stability-indicating gas chromatographic (GC) method was developed and validated for quantitative determination of an halogenated volatile anesthetic isoflurane (ISO) in the presence of degradation products generated under stress conditions. The sample concentration was carried out by means of solid-phase microextraction (SPME) using a 100-μm polydimethylsiloxane (PDMS) fiber, desorbed inside the GC inlet port and analyzed using a GS-Gaspro (30 m × 0.32 mm) capillary column with flame ionization detection (FID). The response was linear over a range of 3.75 to 30.04 μg mL−1 (r = 0.9996). The specificity and stability-indicating capability of the method was verified subjecting ISO to hydrolytic, oxidative, photolytic, and thermal stress conditions. The method showed good recovery (99.54%) with low intra- and inter-day relative standard deviation (RSD) (≤2.5%). A considerable degradation occurred under stress conditions evidenced by an ISO peak area reduction while the degradation product was not detectable. There was no interference of the excipients in the determination of the drug. Thus, the proposed method was found to be stability-indicating and can be used for routine analysis for quantitative determination of ISO liquid anesthetic.

Soft agglomerates containing pantoprazole-loaded microparticles were developed with the aim of prompt delivery of gastro-resistant particles. The objective was to evaluate the relative bioavailability in dogs after the oral administration of soft agglomerates. Gastro-resistant pantoprazole-loaded microparticles prepared by spray drying were mixed with mannitol/lecithin spray-dried powder and agglomerated by vibration. One single oral dose (40mg) was administered to dogs. Each dog received either a reference tablet or hard gelatin capsules containing the agglomerates. The plasma profiles were evaluated by non-compartmental and compartmental approaches, and the pharmacokinetic parameters were determined. The agglomerates presented 100% of drug particle loading and a production yield of 80.5%. The amount of drug absorbed after oral dosing was similar after reference or agglomerate administration, leading to a relative bioavailability of 108%. The absorption lag-time was significantly reduced after agglomerate administration (from 135.5+/-50.6 to 15.0+/-2.5min). The agglomerated gastro-resistant pantoprazole-loaded microparticles reduced time to peak plasma. The agglomerates were equivalent to the reference tablets in terms of extent but not in terms of rate of absorption, showing that this formulation is an alternative to single-unit oral dosing with enteric coating and with the advantage of reducing time to effect.

Methotrexate is a folic acid antagonist and its incorporation into nanoformulations is a promising strategy to increase the drug antiproliferative effect on human breast cancer cells by overexpressing folate receptors. To evaluate the efficiency and selectivity of nanoformulations containing methotrexate and its diethyl ester derivative, using two mechanisms of drug incorporation (encapsulation and surface functionalization) in the in vitro cellular uptake and antiproliferative activity in non-tumoral immortalized human keratinocytes (HaCaT) and in human breast carcinoma cells (MCF-7). Methotrexate and its diethyl ester derivative were incorporated into multiwall lipid-core nanocapsules with hydrodynamic diameters lower than 160 nm and higher drug incorporation efficiency. The nanoformulations were applied to semiconfluent HaCaT or MCF-7 cells. After 24 h, the nanocapsules were internalized into HaCaT and MCF-7 cells; however, no significant difference was observed between the nanoformulations in HaCaT (low expression of folate receptors), while they showed significantly higher cellular uptakes than the blank-nanoformulation in MCF-7, which was the highest uptakes observed for the drug functionalized-nanocapsules. No antiproliferative activity was observed in HaCaT culture, whereas drug-containing nanoformulations showed antiproliferative activity against MCF-7 cells. The effect was higher for drug-surface functionalized nanocapsules. In conclusion, methotrexate-functionalized-nanocapsules showed enhanced and selective antiproliferative activity to human breast cancer cells (MCF-7) being promising products for further in vivo pre-clinical evaluations.

A fast, sensitive, and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous determination of quinine and doxycycline in pharmaceutical formulations. The LC-MS/MS method was carried out on a Sun Fire Waters C18 column (50 mm × 3.0 mm I.D.) and the mobile phase consisted of acetonitrile:0.1% formic acid (75:25, v/v), run at a flow rate of 0.45 mL/min (split 1:3). The injection volume was 10 µL for both standard and samples. The triple quadrupole mass spectrometer equipped with an electrospray source in positive mode (ES+) was set up in multiple reaction monitoring mode (MRM), monitoring the transitions of 325.0 > 307.0 and 445.0 > 428.1, for quinine and doxycycline, respectively. The total analysis time was 2 min and the method was linear in the concentration range of 10–1500 ng/mL for both compounds. Method validation investigated parameters such as the specificity, linearity, precision, accuracy, and robustness, giving results ...

The objective of this work was to verify if hydrophilic gels containing benzophenone-3 loaded nanocapsules (HG-NCBZ3) could improve the sunscreen in vitro effectiveness against UVA radiation and its photostability compared to a conventional hydrogel containing the free sunscreen (HG-BZ3). In parallel, the immune response of the nanostructured system was evaluated by mouse ear swelling test and the local lymph node assay. The nanocapsules were prepared by interfacial deposition of poly(epsilon-caprolactone) and characterized in terms of particle size, polydispersity index, zeta potential, drug content and encapsulation efficiency. HG-NCBZ3 UV scans showed higher absorption intensity values than HG-NCplacebo, prepared using unloaded nanocapsules. Films of the gels were irradiated with UVA light and the BZ3 recovery was evaluated by HPLC. BZ3 recovery decreased from 100% to 29% for HG-BZ3 and to 56% for HG-NCBZ3 after 13 h. After wavelength scans within 13 h, the relative areas under the curves (AUC) decreased from 1.00 to 0.62 for HG-BZ3 and remained constant for HG-NCBZ3. Sensitization assay showed that stimulation indexes lower than 3 for all the hydrogel samples. Formulations did not induce increases higher than 10% in ear swelling, indicating that the hydrogels did not cause cutaneous sensitization in mice. The nanoencapsulation improved both the photostability and the effectiveness of BZ3 compared to the non-encapsulated sunscreen and the topical application of free and nanoencapsulated BZ3 did not produce significant allergy response in mice.

Background and purpose: The effects of systemic treatment with indomethacin-loaded nanocapsules (IndOH-NC) were compared with those of free indomethacin (IndOH) in rat models of acute and chronic oedema. Experimental approach: The following models of inflammation were employed: carrageenan-induced acute oedema (measured between 30 min and 4 h), sub-chronic oedema induced by complete Freund's adjuvant (CFA) (determined between 2 h and 72 h), and CFA-induced arthritis (oedema measured between 14 and 21 days). Key results: IndOH or IndOH-NC produced equal inhibition of carrageenan-elicited oedema. However, IndOH-NC was more effective in both the sub-chronic (33 ± 4% inhibition) and the arthritis (35 ± 2% inhibition) model of oedema evoked by CFA, when compared with IndOH (21 ± 2% and 14 ± 3% inhibition respectively) (P < 0.01). In the CFA arthritis model, treatment with IndOH-NC markedly inhibited the serum levels of the pro-inflammatory cytokines tumour necrosis factor α and IL-6 (by 83 ± 8% and 84 ± 11% respectively), while the levels of the anti-inflammatory cytokine IL-10 were significantly increased (196 ± 55%). The indices of gastrointestinal damage in IndOH-NC-treated animals were significantly less that those after IndOH treatment (58 ± 16%, 72 ± 6% and 69 ± 2%, for duodenum, jejunum and ileum respectively). Conclusions and implications: IndOH-NC produced an increased anti-inflammatory efficacy in long-term models of inflammation, allied to an improved gastrointestinal safety. This formulation might represent a promising alternative for treating chronic inflammatory diseases, with reduced undesirable effects. This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009

Polymeric nanoparticle systems (nanocapsules and nanospheres) present potential applications as drug delivery systems. Nevertheless, their full applications have not been exploited due to their limited shelf life when stored in aqueous medium. Drying polymeric nanoparticles using spray-drying represents a promising platform to improve the physicochemical stability of formulations and/or to control the release of hydrophilic and lipophilic drugs. This article presents a brief overview of the most recent and ongoing research in the use of spray-drying process to prepare and/or to dry polymeric nanoparticles formulations intended for drug administration.