Coupled Diffusion-Binding-Deformation Modelling for Phase-Transition Microneedles-Based Drug Delivery.

Phase-transition microneedles (PTMNs)-based transdermal drug delivery (TDD) is gaining popularity due to its non-invasiveness and ability to deliver a wide range of drugs. PTMNs absorb interstitial skin fluid (ISF) and transport drugs from microneedle (MNs) domain to the skin without polymer dissolution. To establish PTMNs for practical use, one needs to understand and optimise the key parameters governing drug transport mechanisms to achieve controlled drug delivery.

Barium Oxide Doped Magnesium Silicate Nanopowders for Bone Fracture Healing: Preparation, Characterization, Antibacterial and In Vivo Animal Studies.

Magnesium silicate (MgS) nanopowders doped with barium oxide (BaO) were prepared by sol-gel technique, which were then implanted into a fracture of a tibia bone in rats for studying enhanced in vivo bone regeneration. The produced nanopowders were characterized using X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), scanning electron microscope with energy-dispersive X-ray spectrometry (SEM-EDX) and transmission electron microscope (TEM). Mechanical and bactericidal properties of the nanopowders were also determined.

Decentralized systems for the treatment of antimicrobial compounds released from hospital aquatic wastes.

In many developing countries, untreated hospital effluents are discharged and treated simultaneously with municipal wastewater. However, if the hospital effluents are not treated separately, they pose concerning health risks due to the possible transport of the antimicrobial genes and microbes in the environment. Such effluent is considered as a point source for a number of potentially infectious microorganisms, waste antimicrobial compounds and other contaminants that could promote antimicrobial resistance development.

Super-swelling hydrogel-forming microneedle based transdermal drug delivery: Mathematical modelling, simulation and experimental validation.

Super-swelling hydrogel-forming microneedles (HFMNs) based transdermal drug delivery (TDD) is gaining significant interest due to their non-invasiveness and ability to deliver a wide range of drugs. The HFMNs swell by imbibing interstitial skin fluid (ISF), and they facilitate drug transport from the reservoir attached at the base into the skin without polymer dissolution. To develop HFMNs for practical applications, a complete understanding of the drug transport mechanism is required, allowing for controlled TDD and geometrical optimisation.

Translation of Polymeric Microneedles for Treatment of Human Diseases: Recent Trends, Progress, and Challenges.

The ongoing search for biodegradable and biocompatible microneedles (MNs) that are strong enough to penetrate skin barriers, easy to prepare, and can be translated for clinical use continues. As such, this review paper is focused upon discussing the key points (e.g.

Mathematical Modelling, Simulation and Optimisation of Microneedles for Transdermal Drug Delivery: Trends and Progress.

In the last two decades, microneedles (MNs) have received significant interest due to their potential for painless transdermal drug delivery (TDD) and minimal skin damage. MNs have found applications in a range of research and development areas in drug delivery. They have been prepared using a variety of materials and fabrication techniques resulting in MN arrays with different dimensions, shapes, and geometries for delivery of a variety of drug molecules.

Glucose diffusivity in cell-seeded tissue engineering scaffolds.

Objective: To determine the effective glucose diffusion coefficient in cell-seeded porous scaffolds to understand the importance of nutrient diffusion in tissue engineering bioreactors.

Results: Cell growth changed the morphological structure of the scaffolds decreasing the effective pore space and, inevitably, decreasing the effective glucose diffusivity in the chosen scaffolds, namely, collagen, poly(L-lactide) and poly(caprolactone) scaffolds from 3.7 × 10(-9) to 3.

Delivery of large molecular protein using flat and short microneedles prepared using focused ion beam (FIB) as a skin ablation tool.

Many studies have been reported in the literature on the effects of various geometries and lengths of microneedles (MNs) on transdermal drug delivery using a variety of drug molecules. In particular, sharp-tipped MNs have been used to disrupt the top layer of the skin, namely, stratum corneum (SC). It has also been shown that short- and flat-tipped MNs can pierce the SC and they have the potential to increase drug permeability.

A new paradigm for numerical simulation of microneedle-based drug delivery aided by histology of microneedle-pierced skin.

Microneedle (MN) is a relatively recent invention and an efficient technology for transdermal drug delivery (TDD). Conventionally, mathematical models of MNs drug delivery define the shape of the holes created by the MNs in the skin as the same as their actual geometry. Furthermore, the size of the MN holes in the skin is considered to be either the same or a certain fraction of the length of the MNs.

Potential of combined ultrasound and microneedles for enhanced transdermal drug permeation: a review.

Transdermal drug delivery (TDD) is limited by the outer layer of the skin, i.e., the stratum corneum.

Lidocaine carboxymethylcellulose with gelatine co-polymer hydrogel delivery by combined microneedle and ultrasound.

A study that combines microneedles (MNs) and sonophoresis pre-treatment was explored to determine their combined effects on percutaneous delivery of lidocaine from a polymeric hydrogel formulation. Varying ratios of carboxymethylcellulose and gelatine (NaCMC/gel ranges 1:1.60-1:2.

Effect of force of microneedle insertion on the permeability of insulin in skin.

Many experiments conducted in the literature have investigated the effect of microneedles (MNs) on insulin permeation across skin. There are also a number of articles that deal with the effect of MN insertion force in skin. However, there is little known on quantifying the relationship between the effect of MN insertion force and the amount of insulin permeated for given MNs.

Permeability enhancement for transdermal delivery of large molecule using low-frequency sonophoresis combined with microneedles.

Transdermal drug delivery is limited by the high resistance of skin towards diffusion of high-molecular-weight drugs. This is mainly because of the fact that the outer layer of the skin, that is the stratum corneum, can prevent diffusion of molecules whose molecular weight is greater than 500 Da. Sonophoresis can be used to enhance the permeability of the skin.

Potential of biodegradable microneedles as a transdermal delivery vehicle for lidocaine.

There has been an increasing interest in applying biotechnology in formulating and characterising new and innovative drug delivery methods, e.g., drug-loaded biodegradable microneedles within the area of transdermal delivery technology.

Optimizing microneedle arrays to increase skin permeability for transdermal drug delivery.

Improving drug permeability in the skin is one of the most important issues for designing new methods of transdermal drug delivery. Consequently, many techniques have been proposed to effectively deliver drugs across the stratum corneum. The microneedle is a new technology to enhance transdermal delivery of high-molecular-weight drugs.

Optimizing microneedle arrays for transdermal drug delivery: extension to non-square distribution of microneedles.

The technology of fabricating microneedle arrays to deliver high molecular weight drugs across skin in a minimally invasive manner is receiving increasing attention. Microneedle arrays with different geometries have been manufactured using materials such as glass, polymer, metal, etc. However, a framework that can identify the optimum designs of these arrays seems to be lacking.

Modelling transdermal delivery of high molecular weight drugs from microneedle systems.

In the past few years, a number of microneedle designs have been proposed for transdermal drug delivery of high molecular weight drugs. However, most of them do not increase the drug permeability in skin significantly. In other cases, designs developed based on certain criteria (e.