Tendinopathy (also called tendinitis or tendinosis) is a tendon disorder resulting from repetitive motion in the affected area or during athletic activity.It is related to pain and swelling in the affected area, with decreasing mechanical strength and movement.  With the rapid growth of an aging population, there is an increasing incidence of chronic tendinopathy.Current therapeutic options are limited and usually used only for symptomatic relief; although surgical treatment can alleviate some symptoms,  the long-term effect (e.g., tendon adhesion, decrease of mechanical strength and risk of repeated fractures) are unsatisfactory.In these last years, Nanotechnology earned attention for the development of diagnostic and target drug delivery based on a specific design.  Nanoparticles (NPs), which have small size, can improve bioavailability, timed/controlled release of drugs and have more precise targeting to the intracellular delivery. 
In this work, we have developed an innovative approach aiming at treating tendinopathy, and solving the problem of the inflammation in tenosynovitis and tendonitis, while avoiding the fibrosis during the healing process of the tendon.
Acetalated dextran-based NPs are loaded with curcumin (a drug with anti-inflammatory and anti-infective action) and coated with Tannic Acid-Iron (III), two compounds which have shown to have anti-fibrotic effects when combined together. Microfluidics was used for improving the uniformity of the particles size. 
The NPs were produced by nanoprecipitation in a glass-capillary microchip.The size and zeta (ζ)-potential were measured by dynamic light scattering, and the loading degree (LD) and efficiency of encapsulation (EE) determination were performed by high pressure liquid chromatography.
The stability was also investigated in aqueous solution,+4 °C and room temperature.
Furthermore, the morphology of the nanosystem was studied by acquiring transmission electron microscopy (TEM) images and the biocompatibility was screened in tenocytes.
RESULT AND DISCUSSION
The prepared NPs showed a size below 300 nm and ζ-potential of -40 mV, which were characterized by a specific LD and EE of curcumin, respectively around 5% and 50%.The storability has shown good stability over the time at +4 °C compared to the samples kept at room temperature.
Moreover,we investigated also the morphology of these particles by acquiring TEM images,and these results showed uniformity in size regarding the loaded NPs, and the presence of an irregular coating on the surface for the coated ones.The cell viability results proved a good compatibility of this system in tenocytes.
Here,we developed an innovative and easily scalable drug-loaded nanosystem,which has shown a good stability and biocompatibility in vitro.The nanosystem will be next tested for the treatment of tendon inflammation.
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