Suchergebnisse

Novel nanoparticles based on Poloxamer 407 and vegetable oil were produced by high pressure homogenization. Functionalization of those nanoparticles was made by incorporation of folic acid (FA)-Poloxamer 407 conjugate. These nanoparticles showed suitable characteristics for intravenous therapeutic applications similarly to PEGylated albumin-based nanoparticles, previously described by our research group. Here, we found that the absence of albumin at the interface of Poloxamer 407-based nanoparticles improves the overall process of in vitro cellular uptake and nanoparticles disruption inside cancer cells (folate receptor, FR, positive cells). The results present here suggests that interfacial composition of those nanoparticles is of paramount importance for drug trafficking inside cancer cells. ; This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020Programa Operacional Regional do Norte. This work has received funding from the European Union Horizon 2020 research and innovation program under Grant Agreement NMP-06-2015-683356 FOLSMART. Diana Soares da Costa thanks Portuguese Foundation for Science and Technology (FCT) for funding her scholarship SFRH/BPD/85790/2012. ...

The incorporation of bioactive compounds in stealth nanoparticles or nanoemulsions enhances their half-life in systemic circulation and can overcome the problems associated with the free drug. Bovine serum albumin (BSA)-drug conjugates were produced with either methotrexate (MTX), a potent anticancer agent, or vancomycin (VCM), a potent antibiotic. Those conjugates were used to produce functionalized BSA nanoemulsions in a formulation composed by aqueous phase and organic phase. BSA-Folic acid (FA) conjugates were also produced allowing specific folate receptor (FR) mediated targeting of cancer cells (KB cell line). All conjugates had similar effects either in solution or in the form of nanoemulsions: BSA-MTX as anti-proliferative over Caco-2 cell line and BSA-VCM as lower minimum inhibitory concentration (MIC) comparatively to VCM solution on Staphylococcus aureus strain Newman. The production of nanoemulsions using BSA-drug conjugates for obtaining vectors loaded with stabilized drugs offers a good, flexible template for a wide range of medical applications. ; Ana Loureiro (SFRH/BD/81479/2011) holds a scholarship from Fundacao para a Ciencia e a Tecnologia (FCT). Goncalo J. L. Bernardes is a Royal Society University Research Fellow at the Department of Chemistry, University of Cambridge and an Investigador FCT at the Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa. This work has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement NMP4-LA-2009-228827 NANOFOL. This work was supported by FEDER through POFC - COMPETE and by Portuguese funds from FCT through the project ...

Bovine Serum Albumin (BSA) nanoemulsions were produced by high pressure homogenization with a tri-block copolymer (Poloxamer 407), which presents a central hydrophobic chain of polyoxypropylene (PPO) and two identical lateral hydrophilic chains of polyethylene glycol (PEG). We observed a linear correlation between tri-block copolymer concentration and size - the use of 5 mg/mL of Poloxamer 407 yields nanoemulsions smaller than 100 nm. Molecular dynamics and fluorescent tagging of the tri-block copolymer highlight their mechanistic role on the size of emulsions. This novel method enables the fabrication of highly stable albumin emulsions in the nano-size range, highly desirable for controlled drug delivery. Folic Acid (FA)-tagged protein nanoemulsions were shown to promote specific Folate Receptor (FR)-mediated targeting in FR positive cells. The novel strategy presented here enables the construction of size controlled, functionalized protein-based nanoemulsions with excellent characteristics for active targeting in cancer therapy. ; European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement NMP4-LA-2009-228827 NANOFOL. This work was supported by FEDER through POFC – COMPETE and by Portuguese funds from FCT through the project PEst-OE/BIA/UI4050/2014. The authors also thank the FCT Strategic Project of UID/BIO/04469/2013 ...