Development of a thermosensitive hydrogel based on Polaxamer 407 and gellan gum with inclusion complexes (Sulfobutylated-ß-cyclodextrin-Farnesol) as a local drug delivery system.

This work proposes the development of a thermosensitive local drug release system based on Polaxamer 407, also known as Pluronic® F-127 (PF-127), Gellan Gum (GG) and the inclusion complex Sulfobutylated-ß-cyclodextrin (CD) with Farnesol (FOH). Rheological properties of the hydrogels and their degradation were studied. According to the rheological results, a solution of 20% w/v of PF-127 forms a strong gel with a gelling temperature of about 25 °C (storage modulus of 15,000 Pa). The addition of the GG increased the storage modulus (optimal concentration of 0.5 % w/v) twofold without modifying the gelling temperature. Moreover, including 0.5% w/v of GG also increased 6 times the degradation time of the hydrogel. Regarding the inclusion complex, the addition of free CD decreased the viscosity and the gel strength since polymer chains were included in CD cavity without affecting the gelling temperature. Contrarily, the inclusion complex CD-FOH did not significantly modify any property of the formulation because the FOH was hosted in the CD. Furthermore, a mathematical model was developed to adjust the degradation time. This model highlights that the addition of the GG decreases the number of released chains from the polymeric network (which coincides with an increase in the storage modulus) and that the free CD reduces the degradation rate, protecting the polymeric chains. Finally, FOH release was quantified with a specific device, that was designed and printed for this type of system, observing a sustainable drug release (similar to FOH aqueous solubility, 8 µM) dependent on polymer degradation.

HUSP: A Smart Haptic Probe for Reliable Training in Musculoskeletal Evaluation Using Motion Sensors.

As a consequence of the huge development of IMU (Inertial Measurement Unit) sensors based on MEMS (Micro-Electromechanical Systems), innovative applications related to the analysis of human motion are now possible. In this paper, we present one of these applications: a portable platform for training in Ultrasound Imaging-based musculoskeletal (MSK) exploration in rehabilitation settings. Ultrasound Imaging (USI) in the diagnostic and treatment of MSK pathologies offers various advantages, but it is a strongly operator-dependent technique, so training and experience become of fundamental relevance for rehabilitation specialists. The key element of our platform is a replica of a real transducer (HUSP-Haptic US Probe), equipped with MEMS based IMU sensors, an embedded computing board to calculate its 3D orientation and a mouse board to obtain its relative position in the 2D plane. The sensor fusion algorithm used to resolve in real-time the 3D orientation (roll, pitch and yaw angles) of the probe from accelerometer, gyroscope and magnetometer data will be presented. Thanks to the results obtained, the integration of the probe into the learning platform allows a haptic sensation to be recreated in the rehabilitation trainee, with an attractive performance/cost ratio.