Evaluation of new polymer-iodine complexes for the fabrication of medical devices.

Povidone-iodine has been a true success story in the fight against infections by harnessing the antimicrobial and antiviral properties of elemental iodine for water-based applications. However, to date there has been little success in implementing iodine attributes in water-insoluble engineering plastics. Here, we describe the first development of biocidal active polyamide- and polyurethane-iodine complexes at laboratory and commercially relevant scales. These polymer-iodine materials are active against a broad range of microorganisms, including bacteria, yeast and fungi, and can be used as base materials for medical devices. The use of new polymer-iodine complexes for infection prevention in medical devices, such as sutures, catheters and drains, or wound care is expected to have significant positive effects at reducing healthcare-acquired infections. In addition, the materials are expected to find significant applications in other fields, such as air handling with the production of biocidal face masks and air filters to control spread of pathogens.

Water absorption dependence of the formation of poly(vinyl alcohol)-iodine complexes for poly(vinyl alcohol) films

Swelling process improves the mobility of PVA segments, while dyeing process restricts that. And there is a large water absorption dependence on the formation of PVA–iodine complexes.

An Open Labelled, Active Controlled, Three-Arm, Parallel-Group study of the safety and efficacy of the oral formulation of Oral Iodine Complex (RENESSANS) administered alone and in combination with standard interferon therapy in patients suffering from Chronic HCV Hepatitis

Iodine has strong antimicrobial properties and has been used in topical applications as antiseptic. Its systemic use in form of iodine complexes derived from dried seaweed extract is beneficial in treating various disorders. Hepatitis C Virus (HCV) chronic infection is present in 6-10% of the Pakistani population and is a major healthcare burden that could benefit from innovative therapeutic regimens.ObjectiveA pilot study has shown the safety and efficacy of iodine complexes in chronic Hepatitis C virus infection. and this clinical study is aimed to further explore the previous findings.MethodsThis is an open-labeled, active-controlled, three-arm, parallel-group study including 90 patients of chronic HCV infection with each arm having 30 patients. The patient groups received 15mg/day iodine complex only, the standard of care therapy interferon+ribavirin, and iodine complex in combination with interferon+ribavirin regimen for 6 months. Efficacy assessment will base upon post-treatment Rapid Virological Response (RVR) at 4 weeks, Early Virological Response (EVR) at 12 weeks, and End of Treatment Viral Response (ETR) at 24/48 weeks.ResultsAs only 3.33% of patients showed at the ETR with iodine complex alone, combination with interferon+ribavirin showed significant improvement in comparison to interferon+ribavirin alone. Iodine complex+ interferon+ribavirin showed 80% RVR and 90% ETR while the standard of care therapy showed 66.7% RVR and 76.67% ETR, respectively. No additional adverse events of iodine complex were observed.ConclusionIodine complex showed a significant synergistic effect when combined interferon+ribavirin regimen and could be useful in relapsers and non-responders.

An in vitro assessment of anti-SARS-CoV-2 activity of oral preparations of iodine complexes (RENESSANS)

ABSTRACTSince the emergence of CoVID-19 pandemic in China in late 2019, scientists are striving hard to explore non-toxic, viable anti-SARS-CoV-2 compounds or medicines. We determined In Vitro anti-SARS-CoV-2 activity of oral formulations (syrup and capsule) of an Iodine-complex (Renessans). A monolayer of vero cells were exposed to SARS-CoV-2 in the presence and absence of different concentrations (equivalent to 50, 05 and 0.5 μg/ml of I2) of Renessans. Anti-SARS-CoV-2 activity of each of the formulation was assessed in the form of cell survival, SARS-CoV-2-specific cytopathic effect (CPE) and genome quantization. With varying concentrations of syrup and capsule, a varying rate of inhibition of CPE, cells survival and virus replication was observed. Compared to 0.5 μg/ml concentration of Renessans syrup, 5 and 50 μg/ml showed comparable results where there was a 100% cell survival, no CPEs and a negligible viral replication (ΔCT= 0.11 and 0.13, respectively). This study indicates that Renessans, containing iodine, may have potential activity against SARS-CoV-2 which needs to be further investigated in human clinical trials.

Comparison of Iodide, Iodate, and Iodine-Chitosan Complexes for the Biofortification of Lettuce

Iodine is an essential trace nutrient for humans; its deficit can affect motor and cognitive development. Biofortifying crops with iodine is a way of promoting the adequate intake of this element. The uses of chitosan-iodine complexes for crop biofortification have not been previously studied. The present work evaluated the effects of KIO3 and KI salts, chitosan-KIO3 complex (Cs-KIO3), and chitosan-KI complex (Cs-KI) application on lettuce, with a chitosan-only treatment as a control and water as the absolute control. Each treatment involved the application of 0, 5, and 25 mg I kg−1 soil applied before transplanting or 25 mg I kg−1 soil applied as split doses of 12.5 mg kg−1, once immediately before transplanting and the second application 15 days later. Single application of Cs-KIO3 at 5 and 25 mg I kg−1 increased lettuce biomass while the split-dose application (SDA) of Cs-KI (25 mg I kg−1) led to a decrease in biomass. Maximum accumulation of iodine in lettuce was observed after the application of KIO3 (25 mg I kg−1) in two parts. This study shows that the use of chitosan complexes, especially Cs-KIO3, may be a viable alternative for crop biofortification with iodine without affecting crop yields.

Macromolecule/Polymer-Iodine Complexes: An Update

The great chemical affinity of molecular iodine towards several macromolecules and innumerable polymers allows the formation of macromolecule/polymer-iodine complexes, usually commensurate with the desired uses and applications. In many instances, the formation of such complexes occurs through a charge-transfer mechanism. The strength of the ensued complex is more accentuated by the presence of heteroatoms (nitrogen, oxygen, sulfur) and the π-conjugation induced moieties within the chemical structure of the polymer. A wide range of polymers with high specific surface areas and large total pore volumes are excellent candidates for iodine adsorption, suggesting their use in the removal of radioactive iodine in nuclear power plants. The recent results of iodine uptake by polysaccharides such as starch, chitin, chitosan, alginate, and cellulose are but novelties. Complexing vinyl polymers such as poly(N-vinyl-2-pyrrolidone), poly(vinyl pyridine), poly(vinyl alcohol), poly(vinyl chloride), poly(acrylonitrile), and polyacrylics, with molecular iodine revealed special chemistry, giving rise to polyiodide ions (In -) as the actual complexing agents. Carbon allotropes (graphene, graphene oxide, carbon nanotubes, amorphous carbons) and polyhydrocarbons are prone to interact with molecular iodine. The treatment of a broad set of polymers and macromolecules with molecular iodine is but a doping process that ends up with useful materials of enhanced properties such conductivity (electrical, ionic, thermal); in some cases, the obtained materials were of engineering applications. Complexation and doping materials with iodine are also aimed at ensuring the antimicrobial activity, particularly, for those intended for medical uses. In several cases, the impact of the iodine doping of polymer is the alteration of its morphology, as is the case of the disruption of the graphitic morphology of the graphene or graphene oxide.

Extended Assemblies of Ru(bpy)(CO)2X2 (X = Cl, Br, I) Molecules Linked by 1,4-Diiodotetrafluoro-Benzene (DITFB) Halogen Bond Donors

The ruthenium carbonyl compounds, Ru(bpy)(CO)2X2 (X = Cl, Br or I) act as neutral halogen bond (XB) acceptors when co-crystallized with 1,4-diiodotetrafluoro-benzene (DITFB). The halogen bonding strength of the Ru-X⋅⋅⋅I halogen bonds follow the nucleophilic character of the halido ligand. The strongest halogen bond occurs between the chlorido ligand and the iodide atoms of the DITFB. All three halogen bonded complexes form polymeric assemblies in the solid state. In Ru(bpy)(CO)2Cl2⋅DITFB (1) and in Ru(bpy)(CO)2Br2⋅DITFB (2) both halido ligands are halogen bonded to only one DITFB donor. In Ru(bpy)(CO)2I2⋅DITFB (3) only one of the halido ligands is involved in halogen bonding acting as ditopic center for two DITFB donors. The polymeric structures of 1 and 2 are isomorphic wave-like single chain systems, while the iodine complexes form pairs of linear chains attached together with weak F⋅⋅⋅O≡C interactions between the closest neighbors. The stronger polarization of the iodide ligand compared to the Cl or Br ligands favors nearly linear C-I⋅⋅⋅I angles between the XB donor and the metal complex supporting the linear arrangement of the halogen bonded chain.