Poly (vinyl alcohol) microneedles: Fabrication, characterization, and application for transdermal drug delivery of doxorubicin.

Poly (vinyl alcohol) microneedles were fabricated, characterized, and applied to enhance in vitro transdermal delivery of doxorubicin. The microneedles were fabricated using the micromolding technique with the drug load in different locations within the needle array. The polymer solution was assessed for rheological properties, drug dissolution, and chemical structurestudies.

Mesoporous silica-based dosage forms improve bioavailability of poorly soluble drugs in pigs: case example fenofibrate.

Objectives: Mesoporous silicas (SLC) have demonstrated considerable potential to improve bioavailability of poorly soluble drugs by facilitating rapid dissolution and generating supersaturation. The addition of certain polymers can further enhance the dissolution of these formulations by preventing drug precipitation. This study uses fenofibrate as a model drug to investigate the performance of an SLC-based formulation, delivered with hydroxypropyl methylcellulose acetate succinate (HPMCAS) as a precipitation inhibitor, in pigs.

Mesoporous silica-based dosage forms improve release characteristics of poorly soluble drugs: case example fenofibrate.

Objectives: Mesoporous silica-based dosage forms offer the potential for improving the absorption of poorly soluble drugs after oral administration. In this investigation, fenofibrate was used as a model drug to study the ability of monomodal ('PSP A') and bimodal ('PSP B') porous silica to improve release by a 'spring' effect in in vitro biorelevant dissolution tests. Also investigated was the addition of various polymers to provide a 'parachute' effect, that is, to keep the drug in solution after its release.

Physico-chemical characterisation of cationic DOTAP liposomes as drug delivery system for a hydrophilic decapeptide before and after freeze-drying.

In the present study, positively charged 1,2-dioleoyloxy-3-trimethylammoniumpropane (DOTAP) liposomes as a delivery system for a hydrophilic decapeptide were developed. The main objective was the preparation of a stable, highly loaded, lyophilised formulation to yield the basis for an acceptable shelf life. The influences of addition of cholesterol, pH value, amounts of lipid and peptide, type and amount of sugar-based cryoprotective agent (trehalose and sucrose), and time point for cryoprotector addition as well as the freeze-drying process parameters were investigated.

Characterisation and stability studies of a hydrophilic decapeptide in different adjuvant drug delivery systems: a comparative study of PLGA nanoparticles versus chitosan-dextran sulphate microparticles versus DOTAP-liposomes.

Poly[lactic-co-glycolide] (PLGA) nanoparticles, chitosan-dextran sulphate microparticles, and DOTAP-liposomes were prepared as vaccine adjuvants and drug carriers for a small hydrophilic model peptide, and their different physico-chemical properties (size, PDI, zeta-potential, pH-value and peptide loading) were investigated. The model peptide's encapsulation efficiency (EE) in PLGA particles amounted to 15%, for DOTAP-liposomes to 20% and for chitosan particles up to 90%. The structural appearance of the particles was visualized by SEM and TEM.