7 research outputs found
Electrospun nanofiber-based niflumic acid capsules with superior physicochemical properties
The aim of this study was to assess whether nanofibrous drug mats have potential as delivery systems for poorly water-soluble drugs. Amorphous nanofiber mats from a model poorly water-soluble active pharmaceutical ingredient (API), niflumic acid, together with the polymer excipient, polyvinyl pyrrolidine, were prepared by nozzle-free electrospinning. This technique offers a scalable way for drug formulation, and by increasing the surface area of the drug, the dissolution rate and therefore bioavailability of the API can be improved. In this study, both the amount of the dissolved active ingredient and the dissolution kinetics has been improved significantly when the nanofibrous mats were used in the drug formulation. A 15-fold increase in the dissolved amount of the produced amorphous niflumic acid nanofiber was observed compared to the dissolved amount of the raw drug within the first 15鈥塵inutes. Capsule formulation was made by mixing the electrospun nanofibers with a microcrystalline cellulose filler agent. When comparing the dissolution rate of the capsule formulation on the market with the nanofibrous capsules, a 14-fold increase was observed in the dissolved drug amount within the first 15鈥塵inutes
3D-printed electrospinning setup for the preparation of loratadine nanofibers with enhanced physicochemical properties
3D-printed electrospinning setup for the preparation of loratadine nanofibers with enhanced physicochemical properties
Applications of the bi-layer thin film sensor system for registering cardio-respiratory activity
A novel bi-layer thin film sensor system was used for accurately registering physiological parameters associated with body movements, such as cardiac and respiratory activities. The bi-layer curvature sensor system can provide additional medical information about the cardiac activity of the patient by mapping the five characteristic waves of the normal heartbeat rate (P, Q, R, S and T wave). This system was also used for registering physiological parameters such as the monitoring of lung ventilation which can give a range of information about the patients health (normal respiration patterns, deep inhalation/exhalation and apnoea), easily distinguishable in the output signal. The bi-layer thin films used consist of a magnetic layer and a non-magnetic counter layer that is utilized to enhance the changes in the relative permeability of the material caused by tensile or compressive stresses during bending. The measuring system is based on a personal computer in conjunction with the LabVIEW庐 graphical programming package. The nature of this configuration provides the necessary features for sensor signal acquisition, analysis and data presentation. The results from the sensor application on patients demonstrate that this system can provide a robust, cost effective solution to monitoring cardio-respiratory activity with minimum inconvenience to the patient, which is necessary for prolonged, undisturbed monitoring
Thermal stability of bi-layer thin film displacement sensors systems
The bi-layer thin film measurement system uses the principle of frequency modulation for the detection of displacement. The measuring system utilizes a personal computer based system using the LabVIEW庐 graphical programming package that provides the features necessary for acquiring the sensor signal, analyzing it and displaying the results. The results from the acquisition were compared with previously developed amplitude and phase modulation based systems to show that the frequency modulation technique provides a robust and accurate solution to evaluate magnetostrictive materials and their application in magnetic sensors. The performance of the bi-layer thin film sensor was examined and its thermal stability, over the temperature range of up to 180 鈼, was tested in an environmental chamber. The temperature rise does cause inductance change, but the sensor signal remains unaffected due to the nature of the frequency modulation method. Thus, having two materials, with different thermal coefficients of expansion in a bi-layer thin film sensor does not adversely influence the sensor signals. This creates a temperature independent sensor that is needed for applications where there are temperature variations