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Large unilamellar liposomes and multilamellar vesicles consisting of DMPC interacted with cationic phosphorus-containing dendrimers CPDs G3 and G4. DSC and ζ-potential measurements have shown that liposomal-dendrimeric molecular recognition probably occurs due to the interaction between the complementary surface groups. Calorimetric studies indicate that the enthalpy of the transition of the lipids that interact with CPDs is dependent on the dendrimers generation. These results can be used in order to rationally design mixed modulatory liposomal locked-in dendrimeric, drug delivery nano systems. © 2011 Elsevier Ireland Ltd.

Despite the rapid development of modern pharmaceutics, delivery of drugs to sites of action is not always effective. The research on new targeting delivery systems of pharmacologically active molecules is of great importance.Surface properties such as surface charge of drug delivery particles frequently define their pharmacokinetic profile; hence the efficiency of drugs can be increased by application of nanoparticles having appropriate surface properties.The aim of the present work was to study the interactions of cationic phosphorus-containing dendrimers (CPD) with model lipid membranes with no charge or bearing surface charge. The interactions of two generations of phosphorus dendrimers on the thermotropic behavior of model lipid membranes composed of DMPC (uncharged) or DMPC/DPPG (negatively charged) were studied using differential scanning calorimetry (DSC). The results of this study showed that CPDs can alter the thermotropic behaviour of the bilayer by reducing the cooperativity of phospholipids and this effect strongly depends on membrane surface charge. The information resulting from this study may be applied to the rational design of new drug carriers combining liposomal and dendrimeric technology. © 2010 Elsevier B.V.

To investigate the molecular interaction of amyloid beta peptides Aβ1-28 or Aβ25-40 with model lipid membranes differential scanning calorimetry (DSC) and DPH and TMA DPH fluorescence anisotropy approaches were used. The main transition temperature (T m) and enthalpy change (ΔH) of model lipid membranes composed of DMPC/DPPG on addition of Aβ25-40 or Aβ25-40 at 10:1 (w/w) phospholipid/peptide ratio either non-aggregated or previously aggregated were examined. The effect of Aβ1-28 and Aβ25-40 on the membrane fluidity of liposomes made of DMPC/DPPG (98:2 w/w) was determined by fluorescence anisotropy of incorporated DPH and TMA DPH. The results of this study provide information that Aβ1-28 preferentially interacts with the hydrophilic part of the model membranes, while Aβ25-40 rather locates itself in the hydrophobic core of the bilayer where it reduces the order of the phospholipids packing. © 2009 Akadémiai Kiadó, Budapest, Hungary.

Liposomal locked-in dendrimers (LLDs), the combination of liposomes and dendrimers in one formulation, represents a relatively new term in the drug carrier technology. LLDs undergone appropriate physicochemical investigation can merge the benefits of liposomal and dendrimeric nanocarriers. In this study generation 1 and 2 hydroxy-terminated dendrimers were synthesized and were then "locked" in liposomes consisting of DOPC/DPPG. The anticancer drug doxorubicin (Dox) was loaded into pure liposomes or LLDs and the final products were subjected to lyophilization. The loading of Dox as well as its in vitro release rate from all systems was determined and the interaction of liposomes with dendrimers was assessed by thermal analysis and fluorescence spectroscopy. The results were very promising in terms of drug encapsulation and release rate, factors that can alter the therapeutic profile of a drug with low therapeutic index such as Dox. Physicochemical methods revealed a strong, generation dependent, interaction between liposomes and dendrimers that probably is the basis for the higher loading and slower drug release from the LLDs comparing to pure liposomes. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association.

Due to their relative easy synthesis and commercial availability, nanovectors based on dendrimers and dendrons are among the most utilized non‐viral vectors for gene transfer. Concomitantly, recent advances in molecular simulations and computer architectures not only allow for accurate predictions of many structural, energetical, and eventual self‐assembly features of these nanocarriers per se, but are able to yield fundamental information about the interactions of these nanovectors with their nucleic acid cargoes at a molecular level. In this chapter, we aim at presenting some of our own, collaborative efforts in the field of multiscale molecular modeling of these fascinating materials. The contribution is written with the specific purpose of illustrating the potentiality of computational methodologies and the usefulness of multiscale molecular modeling as an innovative and complementary tool in the current experimental research.