tannins and ferric-chloride

Polysaccharide hydrogels have been widely used as wound dressings because of their biocompatibility and ability to provide moist environment for wound healing. However, bacterial infection often delays the healing process. Herein, a novel thermosensitive and pH-sensitive hydroxypropyl chitin/tannic acid/ferric ion (HPCH/TA/Fe) composite hydrogel was fabricated by a simple assembly. The pre-cooled hydrogel precursor solution can be injected onto the irregular wound area and gel rapidly at physiological temperature. The TA not only acted as a crosslinker to enhance mechanical properties of the hydrogel, but also as an antibacterial agent which could be sustainably released in response to the acidic environment. The composite hydrogel showed excellent broad-spectrum antibacterial activity up to 7 days with negligible cytotoxicity. Moreover, the hydrogel can inhibit bacterial infection and accelerate the wound healing process without scars in the mouse experiment. These results indicate the potential application of this composite hydrogel for the infected wound healing.

Topics: Animals; Anti-Bacterial Agents; Bandages; Biocompatible Materials; Chitin; Chlorides; Escherichia coli; Female; Ferric Compounds; Hydrogels; Hydrogen-Ion Concentration; Mice; Mice, Inbred BALB C; NIH 3T3 Cells; Staphylococcus aureus; Tannins; Temperature; Wound Healing

Estrogen receptor-positive (ER+) breast carcinoma therapy faces the challenges of estrogen receptors heterogeneity and endocrine therapy resistance. Selectively attacking glutathione (GSH) biosynthesis which is the metabolic vulnerability of ER+ breast carcinoma could bypass conventional treatment limitations through blocking oxidative stress disorders-driven tumor cell proliferation. Herein, we developed drug-organics-inorganics self-assembled nanosystem (DFTA) with doxorubicin (DOX) as chemotherapeutic agent, ferric chloride (FeCl

Topics: Animals; Antineoplastic Agents; Breast Neoplasms; Chlorides; Doxorubicin; Drug Delivery Systems; Drug Liberation; Female; Ferric Compounds; Glutathione; Humans; MCF-7 Cells; Mice, Inbred BALB C; Receptors, Estrogen; Tannins

This report presents the potential utilization of tannic acid (TA) as a natural iron chelator. TA is capable of binding with small ferric complexes without competitive binding with endogenous iron-containing molecules such as ferritin and transferrin. It was observed that the extracellular iron binding of TA resulted in the formation of self-assembled Fe

Topics: Cell Proliferation; Chelating Agents; Chlorides; Ferric Compounds; Hep G2 Cells; Humans; Iron; Phagocytosis; Tannins

The lifetime of bioprosthetic heart valves (BHVs) is limited by the mechanical damage and calcification. The major components of BHVs are collagen and elastin. Collagen could be well protected by glutaraldehyde (GLUT) crosslinking, while elastin is not stabilized and has a high risk of degradation, which could lead to the calcification of BHVs. We aimed to develop methods for stabilizing elastin and decreasing calcification. We investigated the combined tannic acid (TA) or epigallocatechin gallate (EGCG) with ferric chloride to stabilize elastin and prevent calcification. We found that the amount of TA/EGCG bound to elastin was in a time-dependent pattern and this reaction showed better efficiency in acidic condition and ethanol-water mixed solvents. Moreover, Fe

Topics: Animals; Bioprosthesis; Calcinosis; Catechin; Chlorides; Collagen; Cross-Linking Reagents; Elastin; Ferric Compounds; Glutaral; Heart Valve Prosthesis; Male; Pericardium; Polyphenols; Protein Stability; Rats, Sprague-Dawley; Swine; Tannins; Tensile Strength

A tannin-immobilized glassy carbon electrode (TIGC) was prepared via electrochemical oxidation of the naturally occurring polyphenolic mimosa tannin, which generated a non-conducting polymeric film (NCPF) on the electrode surface. The fouling of the electrode surface by the electropolymerized film was evaluated by monitoring the electrode response of ferricyanide ions as a redox marker. The NCPF was permselective to HAuCl4, and the electrochemical reduction of HAuCl4 to metallic gold at the TIGC electrode was evaluated by recording the reduction current during cyclic voltammetry measurement. In the mixed electrolyte containing HAuCl4 along with FeCl3 and/or CuCl2, the NCPF remained selective toward the electrochemical reduction of HAuCl4 into the metallic state. The chemical reduction of HAuCl4 into metallic gold was also observed when the NCPF was inserted into an acidic gold solution overnight. The adsorption capacity of Au(III) on tannin-immobilized carbon fiber was 29±1.45 mg g(-1) at 60°C. In the presence of excess Cu(II) and Fe(III), tannin-immobilized NCPF proved to be an excellent candidate for the selective detection and recovery of gold through both electrochemical and chemical processes.

Topics: Chlorides; Copper; Electrochemical Techniques; Electrodes; Ferric Compounds; Gold; Gold Compounds; Oxidation-Reduction; Tannins

To develop a method for the study of spinal cord injury (SCI) that can visualize the blood vessels and is compatible with hematoxylin and eosin (HE) staining and immunohistochemical techniques.. Visualization of the vascular changes is important for the study of SCI. The original ferric tannate method can stain the spinal cord vasculature to its terminals, but the diffuse tannate precipitates spoil the delicacy of the picture. More importantly, it is incompatible with HE staining and immunohistochemical techniques, which is crucial for the study of SCI. We thus aimed to develop a modified ferric tannate method that could meet the requirement for the study of SCI.. This study was carried out in China.. The original ferric tannate method involves a two-step procedure: intravascular perfusion of tannic acid, followed by soaking the tissue sections in a solution of ferric chloride. In the modified method both chemicals were delivered through perfusion.. In the original method, diffuse ferric tannate precipitates blurred the profile of the vessels. More importantly, it was incompatible with either HE or immunostaining methods. Our modified method stained the blood vessels with clean background and was compatible with both HE staining and immunohistochemical techniques.. The modified method is far superior to the original method and meets the requirement for the study of SCI.

Topics: Animals; Biomarkers; Blood Vessels; Chlorides; Coloring Agents; Disease Models, Animal; Ferric Compounds; Histocytochemistry; Immunohistochemistry; Male; Nerve Tissue Proteins; Perfusion; Rats; Rats, Sprague-Dawley; Spinal Cord; Spinal Cord Injuries; Staining and Labeling; Tannins

Phosphorus removal from wastewater is of great importance. In the present study, ferric chloride was selected as the coagulant, and tannic acid (TA), a natural polymer, as the coagulant aid to develop an effective coagulation process with the emphasis of phosphorus recovery from different types of wastewater. The results showed that TA can accelerate the settling speed by forming flocs with large size, reduce the residual Fe(III) to eliminate the yellow color caused by Fe(III), and slightly increase the phosphorus removal efficiency. The precipitate formed by TA-aided coagulation showed the advantage of releasing phosphorus faster than ferric phosphate, indicating the possibility of phosphorus recovery from wastewater as slow release fertilizer. To further understand the structural characteristics of the precipitate, analytical techniques such as Raman spectroscopy, X-ray photoelectron spectroscopy and matrix-assisted laser desorption ionization-time of flight mass spectrometry were employed. The analytical results indicated that TA-Fe-P complex was formed during the coagulation/flocculation processes. Solid phase in the precipitate consisted of TA-Fe-P complex, Fe-TA complex and/or ferric hydroxyphosphate.

Topics: Chlorides; Ferric Compounds; Molecular Structure; Phosphorus; Tannins; Waste Disposal, Fluid; Water Purification

A method for quantification of tannins in wine was adapted to determine tannins added to turkey meat. Standard curves containing varying amounts of GSE [0, 0.5, 1.0, 1.5, 2.0, 2.5, and 5.0%, (w/w)] as a source of tannins were developed. The R(2) value of the mean standard curve was 0.9992. The overall percent recovery of GSE in meat was determined to be 54.78%. Results showed that estimation of GSE in four out of five of the spiked samples was less than or equal to 10%. It is unclear as to why spiked samples at 0.048 mg of GSE were always underestimated (25.0%). Overall, the method seems applicable for estimation of tannins in poultry meat and is probably applicable to estimation of tannins in other meat products.

Topics: Animals; Chlorides; Colorimetry; Ferric Compounds; Food Additives; Meat; Plant Extracts; Seeds; Spectrophotometry; Tannins; Turkeys; Vitis

The present study has ultrastructurally applied the tannic acid-ferric chloride (TA-Fe) and the TA-uranyl acetate (TA-UA) methods to thin sections of glutaraldehyde-fixed, unosmicated embedded epiphyseal cartilage from rat tibiae to demonstrate complex carbohydrates. The strongest TA-Fe and TA-UA staining was observed after fixation of the specimens in glutaraldehyde containing TA. TA-Fe (pH 1.5) strongly stained matrix granules presumed to be proteoglycan monomers and chondrocyte secretory granules at various maturational stages but did not stain collagen fibrils and glycogen. TA-UA (pH 4.2) strongly stained matrix granules, intracellular glycogen, and chondrocyte secretory granules, and moderately stained collagen fibrils in the cartilage matrix. Ribosomes and nuclei were not stained above background staining with UA alone. In alpha-amylase-digested specimens, all TA-UA-reactive cytoplasmic glycogen was selectively removed. Testicular hyaluronidase digestion of specimens selectively removed TA-UA staining in matrix granules and all TA-Fe staining. When the pH of the UA solution was reduced to 1.5, TA-UA staining of glycogen and collagen was markedly decreased or absent, whereas staining of anionic sites was unaltered and significantly greater than with UA staining alone. Thus the TA-metal salt methods are pH dependent and allow differential intracellular and extracellular localization of complex carbohydrates in cartilage tissues at the electron microscope level.

Topics: Animals; Cartilage; Chlorides; Collagen; Epiphyses; Ferric Compounds; Hydrolyzable Tannins; Iron; Methods; Organometallic Compounds; Proteoglycans; Rats; Rats, Inbred Strains; Staining and Labeling; Tannins; Uranium

Topics: Chlorides; Coloring Agents; Ferric Compounds; Oxalates; Oxalic Acid; Staining and Labeling; Tannins