Lignosulfonic Acid Sodium Is a Noncompetitive Inhibitor of Human Factor XIa

The anticoagulant activity of lignosulfonic acid sodium (LSAS), a non-saccharide heparin mimetic, was investigated in this study. LSAS is a relatively safe industrial byproduct with similar polyanionic characteristics to that of heparin. Human plasma clotting assays, fibrin polymerization testing, and enzyme inhibition assays were exploited to investigate the anticoagulant activity of LSAS. In normal human plasma, LSAS selectively doubled the activated partial thromboplastin time (APTT) at ~308 µg/mL. Equally, LSAS doubled APTT at ~275 µg/mL in antithrombin-deficient plasma. Yet, LSAS doubled APTT at a higher concentration of 429 µg/mL using factor XI-deficient plasma. LSAS did not affect FXIIIa-mediated fibrin polymerization at 1000 µg/mL. Enzyme assays revealed that LSAS inhibits factor XIa (FXIa) with an IC50 value of ~8 μg/mL. LSAS did not inhibit thrombin, factor IXa, factor Xa, factor XIIIa, chymotrypsin, or trypsin at the highest concentrations tested and demonstrated significant selectivity against factor XIIa and plasmin. In Michaelis–Menten kinetics, LSAS decreased the VMAX of FXIa hydrolysis of a tripeptide chromogenic substrate without significantly changing its KM indicating an allosteric inhibition mechanism. The inhibitor also disrupted the generation of FXIa–antithrombin complex, inhibited factor XIIa-mediated and thrombin-mediated activation of the zymogen factor XI to FXIa, and competed with heparin for binding to FXIa. Its action appears to be reversed by protamine sulfate. Structure–activity relationship studies demonstrated the advantageous selectivity and allosteric behavior of LSAS over the acetylated and desulfonated derivatives of LSAS. LSAS is a sulfonated heparin mimetic that demonstrates significant anticoagulant activity in human plasma. Overall, it appears that LSAS is a potent, selective, and allosteric inhibitor of FXIa with significant anticoagulant activity in human plasma. Altogether, this study introduces LSAS as a promising lead for further development as an anticoagulant.

Studying rheological properties and reactivity of acid solutions with thickening additives

This article is the result of studies of rheological properties and reactivity of acid solutions of technical lignosulfonate, decationized lignosulfonic acid, and hydrochloric acid with the addition of lignosulfonate. Compositions that include lignosulfonate can be used as displacement agents in the development of watered layers with inhomogeneous reservoir properties. The use of thickening additives in acid solutions solves several problems. Slowing the reaction rate will allow the acid flow to leak in the reservoir deeper, with saving of acid capacity. The height viscosity of the compositions increases the sweep efficiency of the bottomhole zone by acid treatment. Due to the fact that thickening additives in the compositions have a high concentration, selective isolation of highly permeable areas of the reservoir can be realized, which, in turn, contributes to the formation of new pore channels.We evaluated the reactivity of acid solutions with thickening additives in the interaction with carbonate samples. The presence of technical lignosulfonate in an acid solution reduces the dissolution rate of samples. Slowing down the reaction rate will allow the acid composition to form long channels of high permeability, which, in turn, increases the efficiency of acid treatment.

Conductivity as a New Monitoring Technique for Zinc Metal Corrosion and Corrosion Processes

The electrical conductivity method was successfully applied to monitor the corrosion and corrosion inhibition processes of zinc metal. Measurements of electrical conductivity at 20.0 oC of three different corrosive solutions (NaCl, HCl and NaOH) were performed with two different concentrations (0.10 and 1.00 M) containing zinc sheets in the absence and presence of four different concentrations of sodium lignosulfonate (1.0, 5.0, 10.0, and 20.0 mM). The analysis of curves that illustrates the changes in electrical conductivity of these solutions provides qualitative information about the strength of corrosion as well as the extent of corrosion inhibition behavior. The results obtained from electrical conductivity measurements revealed that sodium lignosulfonate was an effective corrosion inhibitor in acidic medium (for both 0.10 and 1.00 M HCl) in which it converted into lignosulfonic acid, but was less effective in salt and alkaline media.

A novel green Lignosulfonic acid/Nafion composite membrane with reduced cost and enhanced thermal stability

A green biopolymer, lignosulfonate acid (LSA), was first used as an additive in the Nafion membrane for fuel cell applications. The Nafion/LSA composite membrane displayed enhanced thermal stability and other...

Rheological Properties and Stability Characteristics of Biochar-Algae-Water Slurry Fuels Prepared by Wet Milling

This study was aimed to understand the rheological properties and stability characteristics of biochar-algae-water (BAW) slurry fuels prepared by wet milling. A pine sawdust biochar and a chlorella vulgaris algae were used in preparing the slurry fuels. The BAW slurries were formulated by mixing the biochar, algae, de-ionized water, lignosulfonic acid sodium salt, and then the mixture was ball-milled for various times. The BAW slurries with a constant solid loading of 45 wt % were prepared with varied algae proportion in algae/biochar mixture. The apparent viscosity and stability of BAW slurries were measured. It was found that D50 of the particles of the solid in the slurries decreased with increasing milling time. The viscosity of the slurries decreased first and then increased as milling time increased, reaching a minimal value when D50 of the solid was between 3 and 7 μm. The lowest viscosity of BAW slurries achieved at a given solid loading increased with increasing the algae proportion in the solid. The BAW slurries showed better stability at higher algae proportions due to enhanced flocculation.

SYNTHESIS AND CHARACTERIZATION OF NOVEL SA-PA-LSA/C-30B/AG NANOCOMPOSITES FOR SWELLING, ANTIBACTERIAL, DRUG DELIVERY, AND ANTICANCER APPLICATIONS

Objective: The main objective of this work was to formulate and evaluate Closite-30B/nanoAg filled hydrogel composites which are further intentended to be used for the study of drug delivery,antibacterial, and anticancer activityMethods: In this study, Cloisite-30B (C-30B) clay dispersed biopolymer sodium alginate (SA)-grafted-poly (acrylamide [AAm]-co-lignosulfonic acid) hydrogel composites were synthesized by free radical in situ polymerization reaction technique using SA, AAm, and lignosulfonic acid biopolymers in different proportions in combination. which are subjected to invitro drug delivery and Minimum inhibitory concentration(MIC) method for antibacterial activity study by using Streptococcus faecalis (S.faecalis) and Escherichia coli (E. coli)bacteria. The biocompatibility of the prepared gels were determined by standard protocol HaCaT-cells and MCF-7 cell lines further the prepared hydrogel composites were characterized for particle size,encapsulation efficiency,swelling properties,compatibility studies by FTIR etc.Results: The formulated hydrogels were characterized by X-ray diffraction (XRD) to analyze the particles size and crystallinity. The presence of functional groups and their chemical interaction with the drug, C-30B, and silver nanoparticles (AgNPs) were confirmed by the FTIR spectroscopy. Furthermore, the presence of AgNPs in the matrix was confirmed by ultraviolet/visible spectroscopy. Thermogravimetric analysis was performed to find out the thermal degradation, thermal stability, and the percentage of weight loss at various temperatures. Swelling studies revealed that C-30B and AgNPs induced composites exhibited higher swelling ratio than pure hydrogels. The hydrogels with C-30B/AgNPs displayed excellent antibacterial activity against both Gram-positive and Gram-negative bacteria. Further, these hydrogel composites were loaded with the drug paclitaxel (PT), and drug release study showed that the sustained release of the drug from C-30B/Ag hydrogel matrix compared to rest of other samples. Hydrogel composites were cytocompatible in nature (with HaCaT cells) and the cell viability decreased (with MCF-7cells) with the presence of lignosulfonic acid as well as C-30B and AgNPs in the samples as evaluated through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide to its insoluble formazan assay.Conclusion: The synthesized hydrogel composites were successfully characterized and eavaluated for sustained release of paclitaxel drug delivery at different pHs and temperatures and it is found that C30B/Ag filled composites exhibits contolled release of drug with higher rate, especially at lower pH (pH2) and higher temperature (37oC) and the same formulations which exhibits better anitbcterial and anticancer activity compared to the virgin samples So the prepared C30B/AgNPs hydrogels composites used in drug dlivery for the effective treatment of cancer and used against bacterias and cancerous cells.