Drug delivery strategies generally use inert materials, such as high molecular weight polymers, to encapsulate and control the release rate of therapeutic drugs. Diffusion governs release and depends on the ease of permeation of the polymer alongside the device thickness. Yet in applications such as osteoarthritis, the physiological constraints and limited intra-articular joint space prevent the use of large, solid drug delivery implants. Other investigators have explored the use of micro- and nanoparticle drug delivery systems. However, the small size of the systems limits the total drug that may be encapsulated and its short diffusion distance causes rapid release. Ordinarily, the extremely low diffusivity of a polymer fluid would make this an unsuitable delivery system. Our technology takes advantage of specific molecular interactions between drug and polymer, which can control the rate of release beyond diffusion. With this "affinity-based drug delivery", we have shown that delivery rates from solid polymer can be prolonged from hours and days, to weeks and months. In this paper, we demonstrate that this affinity-based mechanism also applies to low diffusivity fluid-phase polymers. They show release rates that are substantially slower than chemically similar polymers incapable of forming those inclusion complexes. The similarity of this study's liquid polymers to the viscoelastic fluids used in current clinical practice makes it an ample delivery system for osteoarthritic application. We confirmed the capacity of anti-inflammatory delivery of corticosteroids: hydrocortisone, triamcinolone, and dexamethasone; from both solid implants and polymer fluids. Further, we demonstrated that viscoelastic properties are widely tunable, and within the range of native synovial fluid. Lastly, we determined these polymer fluids have no impact on the differentiation of mesenchymal stem cells to cartilage and are not cytotoxic to a common cell line.

A highly sensitive polymerization assay to detect the malaria biomarker hemozoin was accelerated to less than 4 minutes.

ObjectiveA medical device must undergo rigorous regulatory processes to verify its safety and effectiveness while in use. In low-and middle-income countries like Uganda however, medical device innovators and designers face challenges around bringing a device from ideation to being market-ready. This is mainly attributed to a lack of clear regulatory procedures among other factors. In this paper, we illustrate the current landscape of investigational medical devices regulation in Uganda.MethodsInformation about the different bodies involved in regulation of medical devices in Uganda was obtained online. Nine medical device teams whose devices have gone through the Ugandan regulatory system were interviewed to gain insights into their experiences with the regulatory system. Interviews focused on the challenges they faced, how they navigated them, and factors that supported their progress towards putting their devices on the market.ResultsWe identified different bodies that are part of the stepwise regulatory pathway of investigational medical devices in Uganda and roles played by each in the regulatory process. Experiences of the medical device teams collected showed that navigation through the regulatory system was different for each team and progress towards market readiness was fuelled by funding, simplicity of device, and mentorship.ConclusionMedical devices regulation exists in Uganda but is characterised by a landscape that is still in development which thereby affects the progress of investigational medical devices.