Polyelectrolyte Multi-Layered Griseofulvin Nanoparticles: Conventional versus Continuous Layer-by-Layer Fabrication.

Polyelectrolyte multilayers are promising drug carriers with potential applications in the delivery of poorly soluble drugs. Furthermore, the polyelectrolyte multilayer contributes towards electrostatic interactions, which enhances the physical and chemical stability of colloids when compared to those prepared by other approaches. The aim of this work was to generate a polyelectrolyte multilayer on well characterised nanoparticles of the poorly water-soluble drug, griseofulvin.

Application of machine learning in prediction of hydrotrope-enhanced solubilisation of indomethacin.

Systematic in-vitro studies have been conducted to determine the ability of a range of 10 potential hydrotropes to improve the apparent aqueous solubility of the poorly water soluble drug, indomethacin. Solubilisation of the drug in the presence of the hydrotropes was determined experimentally using high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection. These experimental data, together with various known and computed physicochemical properties of the hydrotropes were thereafter used in silico to train an artificial neural network (ANN) to allow for predictions of indomethacin solubilisation.

Duel-acting subcutaneous microemulsion formulation for improved migraine treatment with zolmitriptan and diclofenac: formulation and in vitro-in vivo characterization.

Subcutaneous triptan provides immediate analgesia in migraine and cluster headache but is limited by high pain recurrence due to rapid drug elimination. A dual-acting subcutaneous formulation providing immediate release of a triptan and slow but sustained release of a nonsteroidal anti-inflammatory drug may provide a longer duration of relief. A microemulsion-based technology has various advantages over other technically complex dosage forms.

Effect of repeated compaction of tablets on tablet properties and work of compaction using an instrumented laboratory tablet press.

The repeated compaction of Avicel PH101, dicalcium phosphate dihydrate (DCP) powder, 50:50 DCP/Avicel PH101 and Starch 1500 was studied using an instrumented laboratory tablet press which measures upper punch force, punch displacement and ejection force and operates using a V-shaped compression profile. The measurement of work compaction was demonstrated, and the test materials were ranked in order of compaction behaviour Avicel PH101 > DCP/Avicel PH101 > Starch > DCP. The behaviour of the DCP/Avicel PH101 mixture was distinctly non-linear compared with the pure components.

Characterization of polymer adsorption onto drug nanoparticles using depletion measurements and small-angle neutron scattering.

Production of polymer and/or surfactant-coated crystalline nanoparticles of water-insoluble drugs (nanosuspensions) using wet bead milling is an important formulation approach to improve the bioavailability of said compounds. Despite the fact that there are a number of nanosuspensions on the market, there is still a deficiency in the characterization of these nanoparticles where further understanding may lead to the rational selection of polymer/surfactant. To this end small-angle neutron scattering (SANS) measurements were performed on drug nanoparticles milled in the presence of a range of polymers of varying molecular weight.

Handwashing adherence by visitors is poor: is there a simple solution?

Available evidence suggests that handwashing adherence by visitors to hospital clinics is poor. In this investigation, an audit of 180 people showed that handwashing adherence by visitors to a hospital clinic was 25%, which was very low. Our active method to encourage handwashing led to a marked improvement in adherence from 25% to 68%, increasing to 77% for longer term visitors to the clinic (significance, P < .

Floating dosage forms to prolong gastro-retention--the characterisation of calcium alginate beads.

Floating calcium alginate beads, designed to improve drug bioavailability from oral preparations compared with that from many commercially available and modified release products, have been investigated as a possible gastro-retentive dosage form. A model drug, riboflavin, was also incorporated into the formula. The aims of the current work were (a) to obtain information regarding the structure, floating ability and changes that occurred when the dosage form was placed in aqueous media, (b) to investigate riboflavin release from the calcium alginate beads in physiologically relevant media prior to in vivo investigations.

Developing paediatric medicines: identifying the needs and recognizing the challenges.

There is a significant need for research and development into paediatric medicines. Only a small fraction of the drugs marketed and utilized as therapeutic agents in children have been clinically evaluated. The majority of marketed drugs are either not labelled, or inadequately labelled, for use in paediatric patients.

Influence of ethanol on aspirin release from hypromellose matrices.

Release profiles of aspirin from hypromellose matrices in hydro-ethanolic media were studied. Percent aspirin released increased with increasing levels of ethanol in the dissolution media, correlating with the drug's solubility, however, dose dumping of aspirin did not occur. An initial rapid release was observed in media comprising 40% ethanol.

Citric acid prolongs the gastro-retention of a floating dosage form and increases bioavailability of riboflavin in the fasted state.

A floating dosage form based on calcium alginate beads has been developed. Riboflavin, was selected as the model drug and successfully incorporated into calcium alginate beads. The aims of the current study were to: (a) assess the influence of prolonged gastro-retention on the bioavailability of riboflavin from freeze dried calcium alginate beads administered under varying conditions of food intake and (b) to investigate the potential of citric acid to delay the gastric emptying of the calcium alginate beads.

The use of citric acid to prolong the in vivo gastro-retention of a floating dosage form in the fasted state.

Gastro-retentive dosage forms have the potential to improve local therapy and decrease the variation in bioavailability that is observed with a number of commercially available immediate and modified release preparations. In this study, a dosage form has been developed, utilising freeze-dried calcium alginate beads, designed to float on the surface of the stomach contents thus prolonging the retention time. The aim of the study was to also assess the in vivo behaviour of the radio-labelled calcium alginate beads when they were administered under fasting conditions with either water or an aqueous solution of citric acid, a potential gut transit delaying substance.

The power of ultrasonics.

This overview of ultrasonic technologies describes their effectiveness for a number of applications. Product examples illustrate use for welding, cutting and boring as well as atomising.

The use of hypromellose in oral drug delivery.

Hypromellose, formerly known as hydroxypropylmethylcellulose (HPMC), is by far the most commonly employed cellulose ether used in the fabrication of hydrophilic matrices. Hypromellose provides the release of a drug in a controlled manner, effectively increasing the duration of release of a drug to prolong its therapeutic effect. This review provides a current insight into hypromellose and its applicability to hydrophilic matrices in order to highlight the basic parameters that affect its performance.

Association properties of ethylene oxide/styrene oxide diblock copolymer E17S8 in aqueous solution.

Ethylene oxide and styrene oxide were sequentially polymerized to form the diblock copolymer E(17)S(8) (E = oxyethylene, OCH(2)CH(2); S = oxyphenylethylene, OCH(2)CH(C(6)H(5)); subscripts denote number-average block lengths in repeat units). Light scattering was used to investigate the properties of the micelles formed in dilute solution in the temperature range 15-30 degrees C. The micelles are elongated (probably spheroidal) at the lower temperature and highly elongated (cylindrical, probably wormlike) at the higher temperature.