3D Printers

Personalized 3D Printed Drug Delivery Systems

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Acne is a cruel condition that attacks sufferers’ self-esteem, as well as their skin. It is caused by inflammation of the small oil glands that surround the fine hairs and it leads to infections that can be painful, unsightly and leave permanent facial scars.

Post-pubescent teenagers suffer more than most, but this is a condition that some people suffer with throughout the course of their life.

Could 3D printing have the answer to beating Acne?

The School of Pharmacy at University College London certainly thinks it has a major part to play and recently, in collaboration with FabRx Ltd, tested potential treatments using Fused Deposition Modelling and Stereolithography.

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Antibiotic tablets combined with topical drug treatments are the best options right now, but UCL has devised a system that could render this relatively inefficient treatment redundant.

The theory is quite simple, even if the practicalities really aren’t. The study was based on producing snug-fitting molds of the patient’s nose, loaded with salicylic acid. This helps neutralise the inflammation and exfoliates the skin to remove blockages, so infections simply don’t take hold.

It’s a common ingredient in topical creams and over the counter Acne treatments, but this controlled and constant delivery system could make it a much more potent weapon in the war against Acne. It could also prevent unpleasant side effects like soreness and crusting of the skin by limiting the delivery of the active ingredient.

For this study, the team concentrated on the volunteer’s nose. It tested two potential 3D printing solutions and a variety of material options to find the most effective delivery method.

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First a 3D scan was taken with a Sense 3D scanner and that was converted into a snug-fitting mould loaded with the acid.

In the FDM, commercial FlexEcoPLA, Polycaprolactone and Ninjaflex filaments were loaded with salicylic acid through the process of hot melt extrusion. That filament was then used as feedstock for the printer to create a mold.

PCL is a biocompatible polyester that has often been used in tissue engineering, wound dressings and drug delivery. Here, it simply didn’t hold or diffuse the drug effectively and it did not hold the shape well either.

Ninjaflex is often used in bone implants thanks to its high strength and rigidity, but it reacted badly to the acid and did not hold up well to this particular test.

The team repeated the process with stereolithography, using PEG and PEGDA. This produced devices with higher resolution and higher drug loading (1.9% w/w), increased diffusion and improved performance across the range.

Overall, this study is exceptionally encouraging and these personalised patches and masks show real potential.

It also proved that stereolithography is a much better option for this particular application. It’s a one-step process, the drug loading is more effective, it suffers less with degradation and it diffuses faster to the skin where it can get to work.

Consumer printers made this happen

A simple Makerbot Replicator 2 took care of the FDM molds, while a Form 1+ was used for the SLA molds. So a simple printer is good enough for this treatment and technically a sufferer could make their own moulds at home.

This creates interesting opportunities for drug-loaded devices and patches that could be used to treat all manner of conditions that could benefit from a controlled release system. If that release can be tuned to the individual, then the potential is almost limitless.

It goes beyond the treatment of Acne. That is just the tip of the iceberg. This is a drug delivery system with a vast number of potential applications, from burns to Nicotine patches, and there’s a potentially massive market out there.