Co-encapsulation of human serum albumin and superparamagnetic iron oxide in PLGA nanoparticles: Part I. Effect of process variables on the mean size

PLGA (poly d,l-lactic-co-glycolic acid) nanoparticles (NPs) encapsulating magnetite nanoparticles (MNPs) along with a model drug human serum albumin (HSA) were prepared by double emulsion solvent evaporation method. This Part I will focus on size and size distribution of prepared NPs, whereas encapsulation efficiency will be discussed in Part II. It was found that mean hydrodynamic particle size was influenced by five important process variables. To explore their effects, a five-factorial, three-level experimental design and statistical analysis were carried out using STATISTICA® software. Effect of process variables on the mean size of nanoparticles was investigated and finally conditions to minimize size of NPs were proposed. GAMS™/MINOS software was used for optimization. The mean hydrodynamic size of nanoparticles ranged from 115 to 329 nm depending on the process conditions. Smallest possible mean particle size can be achieved by using low polymer concentration and high dispersion energy (enough sonication time) along with small aqueous/organic volume ratio

Fabrication, Modeling and Characterization of Multi-Crosslinked Methacrylate Copolymeric Nanoparticles for Oral Drug Delivery

Nanotechnology remains the field to explore in the quest to enhance therapeutic efficacies of existing drugs. Fabrication of a methacrylate copolymer-lipid nanoparticulate (MCN) system was explored in this study for oral drug delivery of levodopa. The nanoparticles were fabricated employing multicrosslinking technology and characterized for particle size, zeta potential, morphology, structural modification, drug entrapment efficiency and in vitro drug release. Chemometric Computational (CC) modeling was conducted to deduce the mechanism of nanoparticle synthesis as well as to corroborate the experimental findings. The CC modeling deduced that the nanoparticles synthesis may have followed the mixed triangular formations or the mixed patterns. They were found to be hollow nanocapsules with a size ranging from 152 nm (methacrylate copolymer) to 321 nm (methacrylate copolymer blend) and a zeta potential range of 15.8–43.3 mV. The nanoparticles were directly compressible and it was found that the desired rate of drug release could be achieved by formulating the nanoparticles as a nanosuspension, and then directly compressing them into tablet matrices or incorporating the nanoparticles directly into polymer tablet matrices. However, sustained release of MCNs was achieved only when it was incorporated into a polymer matrix. The experimental results were well corroborated by the CC modeling. The developed technology may be potentially useful for the fabrication of multi-crosslinked polymer blend nanoparticles for oral drug delivery

Retinyl palmitate polymeric nanocapsules as carriers of bioactives

Nanocapsules containing poly(D,L-lactide) shell and retinyl palmitate core have been prepared by the preformed polymer interfacial deposition method. Dynamic light scattering measurements yielded an average hydrodynamic diameter of similar to 220 nm and a polydispersity index of similar to 0.12. Small-angle neutron scattering experiments revealed the presence of two populations of nanocapsules of core diameters similar to 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/c3T3), 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. (C) 2012 Elsevier Inc. All rights reserved.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Estadual Campinas, Inst Quim, BR-13081970 Campinas, SP, BrazilKings Coll London, Inst Pharmaceut Sci, London SE1 9NH, EnglandRutherford Appleton Lab, ISIS STFC, Chilton OX11 0QX, Oxon, EnglandUniv Estadual Campinas, Inst Biol, BR-13081970 Campinas, SP, BrazilUniversidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ciencias Biol, BR-04044020 São Paulo, BrazilUniv Fed Rio Grande do Sul, Fac Farm, BR-90610000 Porto Alegre, RS, BrazilUniversidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ciencias Biol, BR-04044020 São Paulo, BrazilWeb of Scienc