The use of iodine as antiseptic poses some issues related to its low water solubility and high volatility. Stable solid iodine-containing formulations are highly advisable and currently limited to the povidone-iodine complex. In this study, complexes of molecular iodine with 2-hydroxypropyl α-, β- and γ-cyclodextrins were considered water-soluble iodophors and prepared in a solid state by using three different methods (liquid-assisted grinding, co-evaporation and sealed heating). The obtained solids were evaluated for their iodine content and stability over time in different conditions using a fully validated UV method. The assessment of the actual formation of an inclusion complex in a solid state was carried out by thermal analysis, and the presence of iodine was further confirmed by SEM/EDX and XPS analyses. High levels of iodine content (8.3–10.8%) were obtained with all the tested cyclodextrins, and some influence was exerted by the employed preparation method. Potential use as solid iodophors can be envisaged for these iodine complexes, among which those with 2-hydroxypropyl-α-cyclodextrin were found the most stable, regardless of the preparation technique. The three prepared cyclodextrin–iodine complexes proved effective as bactericides against S. epidermidis.

The Periprosthetic Joint Infection (PJI) is one of the most important complications of the joint arthroplasty. This surgical procedure is rising worldwide and is further affecting the public health because of the widespread resistance to antibiotics. New therapeutic strategies and innovative antimicrobial biomaterials development are needed to eradicate pathogens without inducing resistance and accelerating recovery. In this direction, herein Curcumin I- (Cur-) loaded DAC® (Defensive Antibacterial Coating, a hydrogel based on hyaluronic acid conjugated to polylactic acid, hereafter named DAC) has been built on. To incorporate Cur in the DAC, thus obtaining Cur-DAC (Cur ≅ 0.93 mg/g), the generally recognized as safe (GRAS) propylene glycol (PG) was used as cosolvent. The drugs combinations of Cur (≅ 0.93 mg/g) and Vancomycin (Van) (at low dose that is ≅ 0.033 mg/g) within the hydrogel (Cur/Van-DAC) was alsoexperienced . Hydrogels were prepared and characterized by rheological investigations and their erosion together with the drug release profile over the time evaluated in physiological conditions. The nanohydrogels produced upon water dilution were characterized by AFM, DLS, and UV/Vis absorption and emission spectroscopies. Superior Cur stability over pH-, solvent- and photoinduced degradations resulted in the DAC matrix. The photoinduced antimicrobial activity of Cur-DAC against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium was evaluated by spreading loaded DAC-based hydrogel onto titanium disk mimicking prosthesis, thus detecting a good reduction of bacterial load after 30 min of exposure to light and a subsequent decrease of cells number at 24 h in the absence of nutrients. The drug association in Cur/Van-DAC demonstrated the best activity against MRSA, even in the presence of nutrients, with respect to established DAC loaded with high amounts of Van (ranging from 18.7 mg/g to 45.8 mg/g) used during the surgery, due to the photoantibacterial activity of Cur, becoming promising to prevent and control joint infections.

Unfractionated heparin (UFH) and its low-molecular-weight fragments (LMWH) are widely used as anticoagulants for surgical procedures and extracorporeal blood purification therapies such as cardiovascular surgery and dialysis. The anticoagulant effect of heparin is essential for the optimal execution of extracorporeal blood circulation. However, at the end of these procedures, to avoid the risk of bleeding, it is necessary to neutralize it. Currently, the only antidote for heparin neutralization is protamine sulphate, a highly basic protein which constitutes a further source of serious side events and is ineffective in neutralizing LMWH. Furthermore, dialysis patients, due to the routine administration of heparin, often experience serious adverse effects, among which HIT (heparin-induced thrombocytopenia) is one of the most severe. For this reason, the finding of new heparin antagonists or alternative methods for heparin removal from blood is of great interest. Here, we describe the synthesis and characterization of a set of biocompatible macroporous cryogels based on poly(2-hydroxyethyl methacrylate) (pHEMA) and L-lysine with strong filtering capability and remarkable neutralization performance with regard to UFH and LMWH. These properties could enable the design and creation of a filtering device to rapidly reverse heparin, protecting patients from the harmful consequences of the anticoagulant.

Nepafenac is an anti-inflammatory drug used in ophthalmology, marketed as a suspension due to its low aqueous solubility. A solution formulation could provide better bioavailability than suspension and facilitate single unit doses, avoiding the use of preservatives which are required to maintain sterility in multidose packaging. In this study, solubilization of nepafenac was achieved in the presence of randomly methylated β-cyclodextrin (RAMEB) and the actual complexation was assessed by NMR and phase-solubility studies. It was also found that the addition of hydrophilic polymers plays an important role in allowing increased solubilization of nepafenac at the same cyclodextrin concentration. Compared to complexes of nepafenac with other cyclodextrins, only 5% RAMEB was sufficient to solubilize 0.3% (w/v) nepafenac, enabling for the first time the development of an ophthalmic solution that proved chemically and physically stable for 12 months at 25 °C. The formulated solutions of nepafenac were tested for cytotoxicity on human corneal epithelial cells (HCE-2) and the results suggest their potential as a valuable and safe alternative to the commercially available 0.3% (w/v) suspension of the drug.