Effect of pH on the transfer kinetics of an anti-inflammatory drug from polyaspartamide hydrogels to a lipid model membrane

Flurbiprofen release from eudragit RS and RL aqueous nanosuspensions: a kinetic study by DSC and dialysis experiments

“…This in vitro study suggests that the kinetic process involved in drug release is influenced by the different kinds of polymers forming the nanosuspensions acting on drug dissolution rate and membrane disorder [24][25][26][27]36]. The different permeability between the 2 polymers justifies the entity of drug release and interaction with DMPC bilayers, whereas the affinity of the drug to the polymeric matrix leads the rate at which these phenomena occur.…”

“…The results were also compared with dialysis release experiments, which represent a "classical" way of following the release of a drug from a drug delivery system but mimicking a "sink" method with the lack of a cell membrane able to capture the drug. Evaluation of all these results should give useful indications for understanding the influence of different permeability of RL and RS polymers in the drug-membrane interaction and, furthermore, the suitability of DSC for studying the release from polymeric nanoparticulate systems compared with the classical release test by dialysis, thus allowing speculations about the in vivo bioavailability of the investigated drug carrier systems [24][25][26][27].…”

A mechanistic study of the permeation kinetics through biomembrane models: Gemcitabine–phospholipid bilayer interaction

“…When large unilamellar vesicles (LUV) suspended in a drug-containing solution are used as biomembrane models, the main effect is a progressive shift of the transition temperature T m (t) with time t, until a plateau is reached (sometimes after a few days [1][2][3][4][5][6][7][8][9]). The shift is determined by the entry of the drug into the lipid matrix and, to a first approximation, is linear in the time-varying drug concentration, C(t), according to the equation…”

“…In a recent series of papers we had shown that timedependent differential scanning calorimetry (DSC) can be conveniently used to investigate both the dissolution kinetics of a drug (e.g., a drug) into a lipid bilayer [1][2][3][4][5][6][7][8][9] and the kinetics of bilayer crossing by the same drug [10]. The physical principles of our approach can be briefly discussed as follows.…”

Interaction of naproxen amphiphilic derivatives with biomembrane models evaluated by differential scanning calorimetry and Langmuir–Blodgett studies

“…MLV exhibit, under heating, a characteristic transition from the gel (L b ) phase to the liquid crystal (L a ) phase [13][14][15][16] that can be revealed by DSC by measuring the associated thermodynamic parameters (transition temperature, T m , and enthalpy changes, DH). Amphiphilic compounds, interacting with the phospholipid bilayers, may cause modification of the lipid chain packing, resulting in a variation of the transition thermodynamic parameters [11,[16][17][18][19][20][21][22][23][24]. This behavior, which can be analyzed by the Van't Hoff model of the freezing point depression of solutions, has been verified for several classes of chemical compounds, such as anesthetics [24], and applied on theoretical basis by some researchers [24][25][26]; the deviations from the model due to the complex structure as well as to the size of the compounds have been also taken into account [15,27].…”