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The biopharmaceutical properties of supramolecular vesicular aggregates (SVAs) were characterized with regard to their physicochemical features and compared with cationic liposomes (CLs). Neutral and cationic SVAs were synthesized using two different copolymers of poly(aspartyl hydrazide) by thin-layer evaporation and extrusion techniques. Both copolymers were self-assembled in pre-formulated liposomes and formed neutral and cationic SVAs. Gemcitabine hydrochloride (GEM) was used as an anticancer drug and loaded by a pH gradient remote loading procedure, which significantly increased drug loading inside the SVAs. The resulting average size of the SVAs was 100 nm. The anticancer activity of GEM-loaded neutral and cationic SVAs was tested in human alveolar basal epithelial (A549) and colorectal cancer (CaCo-2) cells. GEM-loaded cationic SVAs increased the anticancer activity in A549 and CaCo-2 cells relative to free drug, neutral SVAs, and CLs. In vivo biodistribution in Wistar rats showed that cationic SVAs accumulate at higher concentrations in lung tissue than neutral SVAs and CLs. Cationic SVAs may therefore serve as an innovative future therapy for pulmonary carcinoma.

The blood–brain barrier (BBB) limits the transport of therapeutic molecules from the blood compartment into the brain, thus greatly reducing the species of therapeutic compounds that can be efficiently accumulated in the central nervous system (CNS). Various strategies have been proposed for improving the delivery of drugs to this tissue, and numerous invasive and noninvasive methods have been proposed by different scientists in an attempt to circumvent the BBB and to increase the delivery of drug compounds into the brain. An interesting alternative, in the solution of this problem and also that of reaching a suitable target in the CNS, has recently been provided through the use of nanoparticulate colloidal devices as a noninvasive technique for brain drug delivery. These systems offer diverse advantages over invasive strategies, because (1) they are designed using biocompatible and biodegradable materials; (2) they avoid the disruption and/or modification of the BBB; and (3) they modulate the biopharmaceutical properties of the entrapped drugs. Moreover, the possibility of targeting specific brain tissue, thanks to ligands linked to the surface of the nanoparticulate colloidal devices, confers the necessary characteristics for the treatment of CNS pathologies to these drug carriers. The aim of this review is to focus on describing the main strategies in use for designing nanoparticulate colloidal devices for CNS delivery, their potentiality as noninvasive strategies in the delivery of drugs to the cerebral tissues, and their biological and clinical applications in cerebral drug delivery. © 2010 Wiley Periodicals, Inc. Med Res Rev 31:716-756, 2011

The interaction of MTX and some aliphatic his(amide) derivatives with synthetic 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) biomembranes was investigated. The drug-membrane model interaction was carried out by differential scanning calorimetry. Anticancer activity of MIX his(amides) was evaluated on cultures of a human leukemic cell line (CCRF-CEM) in comparison with MTX. Compounds were tested at a concentration ranging between 10 nM and 1 μM. The MTX is able to interact with the outer part of the phospholipid bilayers due to its polar nature. Results showed that the amide derivatives of MTX, presenting a marked lipophilic character, are able to interact with the hydrophobic core of the DPPC bilayers, thus perturbing the packing order of the phospholipid bilayers. Particularly, a reduction of the enthalpy values linked to the transition from the gel state to the liquid crystal state of DPPC membranes was observed. This effect is a function of the type and molar fraction of the various compounds. The in vitro antitumor activity on leukemic CCRF-CEM cells was higher for MTX-bis(tetradecylamide) than for the other derivatives. The biological effectiveness of the various MTX derivatives correlates very well with the enthalpy of the transition of drug-loaded DPPC biomembranes.

The blood–brain barrier (BBB) limits the transport of therapeutic molecules from the blood compartment into the brain, thus greatly reducing the species of therapeutic compounds that can be efficiently accumulated in the central nervous system (CNS). Various strategies have been proposed for improving the delivery of drugs to this tissue, and numerous invasive and noninvasive methods have been proposed by different scientists in an attempt to circumvent the BBB and to increase the delivery of drug compounds into the brain. An interesting alternative, in the solution of this problem and also that of reaching a suitable target in the CNS, has recently been provided through the use of nanoparticulate colloidal devices as a noninvasive technique for brain drug delivery. These systems offer diverse advantages over invasive strategies, because (1) they are designed using biocompatible and biodegradable materials; (2) they avoid the disruption and/or modification of the BBB; and (3) they modulate the biopharmaceutical properties of the entrapped drugs. Moreover, the possibility of targeting specific brain tissue, thanks to ligands linked to the surface of the nanoparticulate colloidal devices, confers the necessary characteristics for the treatment of CNS pathologies to these drug carriers. The aim of this review is to focus on describing the main strategies in use for designing nanoparticulate colloidal devices for CNS delivery, their potentiality as noninvasive strategies in the delivery of drugs to the cerebral tissues, and their biological and clinical applications in cerebral drug delivery. © 2010 Wiley Periodicals, Inc. Med Res Rev 31:716-756, 2011