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OrBiTo is a new European project within the IMI programme in the area of oral biopharmaceutics tools that includes world leading scientists from nine European universities, one regulatory agency, one non-profit research organization, four SMEs together with scientists from twelve pharmaceutical companies. The OrBiTo project will address key gaps in our knowledge of gastrointestinal (GI) drug absorption and deliver a framework for rational application of predictive biopharmaceutics tools for oral drug delivery. This will be achieved through novel prospective investigations to define new methodologies as well as refinement of existing tools. Extensive validation of novel and existing biopharmaceutics tools will be performed using active pharmaceutical ingredient (API), formulations and supporting datasets from industry partners. A combination of high quality in vitro or in silico characterizations of API and formulations will be integrated into physiologically based in silica biopharmaceutics models capturing the full complexity of GI drug absorption. This approach gives an unparalleled opportunity to initiate a transformational change in industrial research and development to achieve model-based pharmaceutical product development in accordance with the Quality by Design concept. Benefits include an accelerated and more efficient drug candidate selection, formulation development process, particularly for challenging projects such as low solubility molecules (BCS II and IV), enhanced and modified-release formulations, as well as allowing optimization of clinical product performance for patient benefit. In addition, the tools emerging from OrBiTo are expected to significantly reduce demand for animal experiments in the future as well as reducing the number of human bioequivalence studies required to bridge formulations after manufacturing or composition changes.

To develop self-assembling polymers forming polymeric micelles and increasing the solubility of poorly soluble drugs, amphiphilic polymers containing a hydrophilic PEG moiety and a hydrophobic moiety derived from monoglycerides and polyethers were designed. The biodegradable copolymers were obtained via a polycondensation reaction of polyethylene glycol (PEG), monooleylglyceride (MOG) and succinic anhydride (SA). Polymers with molecular weight below 10,000 g/mol containing a minimum of 40 mol% PEG and a maximum of 10 mol% MOG self-assembled spontaneously in aqueous media upon gentle mixing. They formed particles with a diameter of 10 nm although some aggregation was evident. The critical micellar concentration varied between 3 x 10(-4) and 4 x 10(-3) g/ml, depending on the polymer. The cloud point (>= 66 degrees C) and flocculation point (>= 0.89 M) increased with the PEG chain length. At a 1% concentration, the polymers increased the solubility of poorly water-soluble drug candidates up to 500-fold. Drug solubility increased as a function of the polymer concentration. HPMC capsules filled with these polymers disintegrated and released model drugs rapidly. Polymer with long PEG chains had a lower cytotoxicity (MTT test) on Caco-2 cells. All of these data suggest that the object polymers, in particular PEG1000/MOG/SA (45/5/50) might be potential candidates for improving the oral biopharmaceutical performance of poorly soluble drugs. (C) 2009 Elsevier B.V. All rights reserved.

Di-block copolymers composed of polyethylene glycol (PEG) and a second block of (co)polyesters of F-caprolactone (CL) and/or trimethylene carbonate (TMC) were synthesized and characterized. Tin octoate was used as catalyst and polymerization were completed over a period of 24h with high conversion (> 95%). Self-assembling properties in water were evaluated. All di-block copolymers behave similarly except when PCL served as the second block. Stable crew-cut micelles of about 20 nm were obtained by direct dissolution of the liquid di-block copolymers in water at room temperature. When PCL was present as the second block, no solubilization occurred. Drug encapsulation of poorly water-soluble drugs belonging to biopharmaceutics classification system (BCS) class 11 (ketoprofen and furosemide) was evaluated. Experimental solubility for these two drugs shows a significant enhancement such that a maximum value of 23.4 mg/ml was obtained for ketoprofen in a 10% w/v micellar solution as compared to 0.14 mg in water. In the case of furosemide, the solubility increased from 0.04 mg/ml in water to about 3.2 mg/ml in a 10% w/v micellar solution. Enzymatic degradation of di-block copolymers was also studied in the presence of Pseudomonas lipase in a phosphate buffer solution (pH 7.4). Results indicated rapid degradation of copolymers containing relatively higher amounts of CL compared to TMC suggesting the potential in vivo degradation.

The mineral resource management function of AGL manages three prospecting licences and two mining licences. At least ten pits/prospects are scattered along the two limbs of the Damang anticline with two main types of mineralisation, palaeoplacer and hydrothermal. The Sarbannes-Oxley (SOX) Act 2002 was passed by the US Congress to protect investors by approving the accuracy and reliability of corporate disclosures and Section 404 includes the rules required and internal control, evaluation and reporting. AGL procedures for management assessment of internal controls are implemented to treat each mineralisation type in the best way for reliable resource outputs and estimates. All relevant geological and geostatistical inputs conform to procedures outlined under SOX404 requirements and sign-offs are designed to ensure that technical personnel involved in all aspects of resource and reserve generation are satisfied and can be held accountable. Final models are usually the product of auditable resources which are passed to the mine planning department for scheduling and optimisation. A financial model is produced and reported accordingly., The mineral resource management function of AGL manages three prospecting licences and two mining licences. At least ten pits/prospects are scattered along the two limbs of the Damang anticline with two main types of mineralisation, palaeoplacer and hydrothermal. The Sarbannes-Oxley (SOX) Act 2002 was passed by the US Congress to protect investors by approving the accuracy and reliability of corporate disclosures and Section 404 includes the rules required and internal control, evaluation and reporting. AGL procedures for management assessment of internal controls are implemented to treat each mineralisation type in the best way for reliable resource outputs and estimates. All relevant geological and geostatistical inputs conform to procedures outlined under SOX404 requirements and sign-offs are designed to ensure that technical personnel involved in all aspects of resource and reserve generation are satisfied and can be held accountable. Final models are usually the product of auditable resources which are passed to the mine planning department for scheduling and optimisation. A financial model is produced and reported accordingly.

Self-assembling polymeric surfactant, mmePEG(750)P(CL-co-TMC) [monomethylether poly(ethylene glycol)(750)-poly(caprolactone-co-trimethylene carbonate)], increases drug solubility and crosses an enterocyte monolayer both in vitro and in vivo. The aims of the present work were to investigate whether mmePEG(750)P(CL-co-TMC) polymers can diffuse passively through lipid bilayer using parallel artificial membrane permeability assay (PAMPA) and affect membrane properties using liposomes as model. The mmePEG(750)P(CL-co-TMC) polymer was able to cross by passive diffusion an enterocyte-mimicking membrane in PAMPA at concentration which did not perturb membrane integrity. A weak rigidification associated with a low increase in permeability of liposomal lipid bilayers was observed. These data suggest that polymeric surfactants can cross the lipid membrane by passive diffusion and interact with lipid bilayers.

Monomethylether poly(ethyleneglycol)(750)-poly(caprolactone-co-trimethylene carbonate) (mmePEG750)P(CL-co-TMC)) which spontaneously form micelles, can cross lipid bilayers via passive diffusion and demonstrate an oral bioavailability of 40% in rats. The aim of the current work was to study the transport mechanism(s) of drug-loaded mmePEG750P(CL-co-TMC) micelles across the intestinal barrier. The transport of radiolabelled polymer across Caco-2 cell monolayer was investigated by disrupting tight junctions and by inhibiting endocytosis. The polymer and drugs loaded in micelles independently crossed Caco-2 cell monolayers and did not use either the paracellular route or M-cells. The polymer did not affect P-gp pumps. This mechanistic study suggests that whereas drug-loaded micelles were absorbed by fluid-phase endocytosis, polymeric unimers diffused passively across the membrane concomitantly with micellar endocytosis.

The aim of this work was to evaluate the potential of self-assembling poly(ethyleneglycol)(750)-block-poly(epsilon-caprolactone-co-trimethylenecarbonate)(4500) 50/50 copolymers (PEG-p(CL-co-TMC)) to solubilize amphotericin B in polymeric micelles and to disaggregate the drug to the less toxic monomeric form. Amphotericin B was encapsulated in the micelles upon dilution of a mixture of the liquid polymer and the drug in water. Its solubility was increased by two orders of magnitude depending on polymer concentration. The aggregation state of amphotericin B was decreased by PEG-p(CL-co-TMC). The preparation method and the loading of the polymeric micelles influenced it. The antifungal activity of the drug was reduced by encapsulation in the polymeric micelles whereas the onset of amphotericin B-induced hemolysis was delayed. PEG-p(CL-co-TMC) micelles could be an easy method for amphotericin B encapsulation.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1979., MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING., Bibliography: leaves 67-68., by M. Bradham Brewster., B.S.

Two density functional methods, B3/LYP/6-31+G(d) and B3/PW91/6-31G(d,p) have been used to investigate some possible decomposition pathways for methyl nitrate. Two likely ones were found to be (a) loss of NO2, followed by eventual rearrangement to H2C-OH, and (b) formation of H2C=O and HONO. The initial energy requirement for each process is about 40 kcal/mole, and the second is exothermic, delta H = -16 kcal/mole of H3CO-NO2. The B3/LYP procedure is found to underestimate the H3CO-NO2 and H3C-ONO2 dissociation energies by about 7 kcal/mole.