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In this study, a sulfonation approach using chlorosulfonic acid (CSA) to prepare cellulose sulfate nanofibers (CSNFs) from raw jute fibers is demonstrated. Both elemental sulfur content and zeta potential in the CSNFs are found to increase with increasing CSA content used. However, the corresponding crystallinity in the CSNFs decreases with the increasing amount of CSA used due to degradation of cellulose chains under harsh acidic conditions. The ammonium adsorption results from the CSNFs with varying degrees of sulfonation were analyzed using the Langmuir isotherm model, and the analysis showed a very high maximum ammonium adsorption capacity (41.1 mg/g) under neutral pH, comparable to the best value from a synthetic hydrogel in the literature. The high ammonium adsorption capacity of the CSNFs was found to be maintained in a broad acidic range (pH = 2.5 to 6.5). [ABSTRACT FROM AUTHOR]

Thermoresponsive hydrogels based on ionic cellulose/chitosan are widely used various fields, such as smart windows and tissue engineering, while the effect of carbohydrate backbones of cellulose/chitosan on the thermal response and mechanical properties of hydrogels has received less attention so far. Herein, poly(2(dimethylamino)ethyl methacrylate) (PDMAEMA)-grafted cellulose sulfate (P-CS) and PDMAEMA-grafted chitosan sulfate (P-CHS) as research models are successfully synthesized through multi-step reactions. The P-CS and P-CHS polymers are further applied in crosslinked polyacrylamide networks, resulting in the P-CS and P-CHS hydrogels. Compared to P-CS hydrogels, P-CHS hydrogels could obviously block the transmission of visible light when the temperature is changed from 25 to 42 °C. In contrast to P-CHS hydrogels, the P-CS hydrogels change easily from soft and weak state to stiff and strong state according to their mechanical behaviors. These results indicate that different carbohydrate backbones of cellulose and chitosan should have caused distinct aggregation behaviors of corresponding P-CS and P-CHS hydrogels, which are accompanied by different light transmittance and mechanical properties. Thermoresponsive hydrogels using PDMAEMA-grafted ionic cellulose sulfate (P-CS) and chitosan sulfate (P-CHS) are successfully prepared. Distinct carbohydrate backbone displayed different effects on the thermoresponsive and mechanical properties of hydrogels. [ABSTRACT FROM AUTHOR]

In this study, a sulfonation approach using chlorosulfonic acid (CSA) to prepare cellulose sulfate nanofibers (CSNFs) from raw jute fibers is demonstrated. Both elemental sulfur content and zeta potential in the CSNFs are found to increase with increasing CSA content used. However, the corresponding crystallinity in the CSNFs decreases with the increasing amount of CSA used due to degradation of cellulose chains under harsh acidic conditions. The ammonium adsorption results from the CSNFs with varying degrees of sulfonation were analyzed using the Langmuir isotherm model, and the analysis showed a very high maximum ammonium adsorption capacity (41.1 mg/g) under neutral pH, comparable to the best value from a synthetic hydrogel in the literature. The high ammonium adsorption capacity of the CSNFs was found to be maintained in a broad acidic range (pH = 2.5 to 6.5).

In this study, the removal of Cr(VI) from contaminated waters was studied via a chemical reduction of Cr(VI) on cellulose sulfate microfibers coated with palladium nanocatalyst. In this catalytic procedure, hydrogen gas was generated utilizing an electrochemical cell containing graphite electrodes. Characterization of the prepared catalyst was done using scanning electron microscopy, energy-dispersive X-ray analysis, Fourier-transformed infrared spectroscopy, and thermalgravimetric analyses. The Box-Behnken model of response surface methodology was used to optimize the adsorption process. The effects of main variables including current density, initial concentration of Cr(VI), and time and their interactions on the removal efficiency of Cr(VI) were assessed. Under the optimal conditions (0.1 A and 15 min), the removal efficiency of 98% was achieved for Cr(VI). The examination of recovery indicated that the performance of the prepared catalyst decreased about 10% after 10 cycles of usage. [ABSTRACT FROM AUTHOR]

Cellulose sulfate was synthesized by esterification of α-cellulose with concentrated sulfuric acid at −10°C in ethanol. Cellulose is mainly sulfated on 3-, 6- and 3, 6-positions of the cellulose. It acts as a heterogeneous catalyst for the ring-opening of epoxides with alcohols or anilines and the Friedel-Crafts reaction between N-benzylindole and crotonaldehyde at room temperature. Methanolysis of cyclic epoxides, styrene oxide, terminal aliphatic epoxides, and glycidyl ethers were carried out using the catalyst (0.4–6.8 mg/mmol of epoxide) and afforded the corresponding products in 53–97% isolated yields after 10 min–24 h. Cellulose sulfate was successfully recycled and reused up to 3 catalytic cycles for the ring-opening of styrene oxide with methanol. [ABSTRACT FROM AUTHOR]

Since 1980 after introducing the concept of live cell encapsulation by Lim et al., this technology has received enormous attention. Several studies have been conducted to improve this technique; different polymers, either natural or synthetic, have been used as microcapsules' making materials and different substances as coating layers. Literature review leads us to the conclusion that alginate (Alg) multilayer microcapsules and, in particular, alginate-poly l-lysine (PLL)-alginate (APA) are the most used structures for live cell encapsulation. Although, disadvantages of PLL (e.g., weak mechanical strength and low biocompatibility) made researchers work on other cationic polymers to find an alternative. This review aims to discuss more popularly suggested cationic polymers such as poly l-ornithine (PLO), chitosan, etc. As alternatives for PLL and, more importantly, we want to take a closer look to see which one of these systems are closer to clinical applications. [ABSTRACT FROM AUTHOR]

Cellulose sulfates (CS) with low degree of substitution (DS) and high degree of polymerization (DP) were prepared via a controlled sulfation modification. The obtained CS with DS 0.42 and DP 293 showed an enhanced solubility of 14.7 g/100 g in the ionic liquid 1-ethyl-3-methylimidazolium acetate (EMIMAc) compared to unmodified cellulose. The rheological study revealed that the CS/EMIMAc solution behaved as polymers in a θ solvent with the unique three-region flow curves under shear stress. It also showed a property of typical polyelectrolyte solution with the overlap concentration (c*) of 0.2 wt% and the entanglement concentration (ce) of 3.0 wt%, respectively. The CS/EMIMAc solution with a concentration of 5 wt% was selected to develop polyelectrolyte complex (PEC) with chitosan using extrusion-spherization and emulsification-solvent evaporation. The produced PEC beads and magnetic microspheres had an average size of 1.0 mm and 22.1 µm, respectively. The PEC microspheres showed greater absorption capability for bovine serum albumin than the beads with the maximum adsorption value of 780 mg/g. [ABSTRACT FROM AUTHOR]

Water-soluble polysaccharides of cellulose sulfate (NaCS) and chitosan hydrochloride (CHC) were chosen as the brick materials, while sodium tripolyphosphate (STPP) as a special "cement", the NaCS/CHC/STPP hydrogel films loaded with Ibuprofen were fabricated via self-assembly method. The prepared hydrogel films were characterized via SEM, FTIR, TGA and XRD. It manifested that the hydrogel films formed a dense three-dimensional network with a regular shape, and NaCS, CHC and STPP were involved in the formation of polyelectrolyte complex via electrostatic interaction. The Ibuprofen-loaded hydrogel films possessed respective loading and encapsulation efficiency of 43.15 ± 4.88% and 60.65 ± 4.68%. It verified that the hydrogel films had favourable sustained release profile during 1440 min test, in which Ibuprofen could penetrate through the skin of mouse in a transdermal drug delivery (TDD) model. The cytotoxicity assays indicated that the hydrogel films had non-toxicity and good biocompatibility. All these results shed light on the hydrogel films prepared could be used to design potential TDD vehicles. [ABSTRACT FROM AUTHOR]

Articular cartilage has limited healing and self-repair capability. Damage to articular cartilage becomes irreversible leading to osteoarthritis, which can impact a person's quality of life. Approximately, 5–10% of cartilage tissue is made up of sulfated glycosaminoglycans (GAGs), which sequester growth factors as well as provide structural integrity to the native cartilage tissue. This study evaluated the chondrogenic differentiation of human mesenchymal stem cells (MSCs) on gelatin-based scaffolds containing partially sulfated cellulose (pSC), a GAG mimetic derived from cellulose, in comparison to native GAGs, chondroitin sulfate-A (CS-A) and chondroitin sulfate-C (CS-C), where pSC has similarity to CS-C in terms of degree and pattern of sulfation. Scaffolds were prepared by electrospinning gelatin with pSC or the native GAGs. All scaffolds consist of fibers having average diameters of approximately 3 μm and inter-fiber spacing of approximately 30 μm and were hydrolytically stable throughout the culture. MSCs cultured on pSC containing scaffolds showed early production of sulfated GAGs and higher collagen type II to type I ratio than native GAGs. Among the native GAGs, chondrogenesis was promoted to a greater extent for CS-C in comparison to CS-A containing scaffolds, which suggests the pattern of sulfation impacts chondrogenesis. Partially sulfated cellulose could be used as a potential GAG mimic for cartilage tissue engineering applications. [ABSTRACT FROM AUTHOR]

BackgroundTopical microbicides against the human immunodeficiency virus (HIV) 1 that are nonirritating to the female genital epithelium are urgently needed to slow the heterosexual spread of HIV infection. Products that are also effective contraceptives provide additional benefits. Cellulose sulfate (CS) is a noncytotoxic antifertility agent that exhibits in vitro antimicrobial activity against sexually transmitted pathogens, including HIV.MethodsWe performed a multicenter, Phase I, placebo-controlled, randomized study to evaluate the genital toxicity of CS. Two cohorts of healthy women used 3.5 ml of 6% CS gel or 3.5 ml of K-Y Jelly, vaginally, bid, for 14 days. The first cohort was sexually abstinent, and the second cohort was sexually active.ResultsCS was associated with only a slightly higher odds ratio (OR) of symptoms of minor urogenital irritation compared to the inactive lubricant K-Y Jelly (OR=2.02, 95% confidence interval=0.90-4.53). In addition, there were minor shifts in some genital flora, but there was no evidence of greater inflammation as evidenced by few colposcopic findings, decreased influx of polymorphonuclear cells and minimal changes in proinflammatory cytokines. Moreover, both products appeared acceptable to most women. Product leakage was identified as more of a problem in sexually abstinent women, but less so in women using the product for sexual intercourse, as would be the case in actual practice.ConclusionCS was safe for twice-daily use for 14 days. CS is appropriate for future studies in effectiveness trials.

Cellulose sulfate is a cellulose derivative with unique biological properties. Due to its antibacterial, antiviral and anticoagulant effects, it has good biodegradability and biocompatibility, and is non-toxic and environmentally friendly. Therefore, it has broad application prospects in the fields of food, medicine and chemical industry. However, cellulose sulfate has not been used commercially yet, and its preparation methods of cellulose sulfate are mainly divided into three categories. They are homogeneous preparation method, heterogeneous preparation method and quasi-homogeneous prepraration method. In this paper, the preparation methods of cellulose sulfate were summarized, and the characteristics of each preparation method were analyzed. It provided a theoretical basis for the preparation of cellulose sulfates with controlled properties such as degree of substitution and molecular weight. [ABSTRACT FROM AUTHOR]

Spinal cord injury can lead to severe dysfunction as a result of limited nerve regeneration that is due to an inhibitory environment created at the site of injury. Neural tissue engineering using materials that closely mimic the extracellular matrix (ECM) during neural development could enhance neural regeneration. Glycosaminoglycans (GAGs), which are sulfated polysaccharides, have been shown to modulate axonal outgrowth in neural tissue depending upon the position and degree of sulfation. Cellulose sulfate (CelS), which is a GAG mimetic, was evaluated for its use in promoting neurite extension. Aligned fibrous scaffolds containing gelatin blended with 0.25% partially sulfated cellulose sulfate (pCelS), having sulfate predominantly at the 6-carbon position of the glucose monomer unit, and fully sulfated cellulose sulfate (fCelS), which is sulfated at the 2-, 3-, and 6-carbon positions of the glucose monomer unit, were fabricated using the electrospinning method. Comparisons were made with scaffolds containing native GAGs, chondroitin sulfate-A (CS-A) and chondroitin sulfate-C (CS-C), which were obtained from commercial sources. CS-A and CS-C are present in neural tissue ECM. The degree of sulfation and position of sulfate groups was determined using elemental analysis, Fourier-transform infrared spectroscopy (FTIR), Raman microspectroscopy, and 13C nuclear magnetic resonance (NMR). In vitro studies examined both nerve growth factor (NGF) binding on scaffolds and neurite extension by dorsal root ganglion (DRG) neurons. NGF binding was highest on scaffolds containing pCelS and fCelS. Neurite extension was greatest for scaffolds containing fCelS followed by pCelS, with the lowest outgrowth on the CS-A containing scaffolds, suggesting that the degree and position of sulfation of CelS was permissible for neurite outgrowth. This study demonstrated that cellulose sulfate, as a GAG mimetic, could be used for future neural tissue regeneration application. Scaffolds that closely mimic the native extracellular matrix (ECM) during development may be a promising approach to enhance neural regeneration. Here, we reported a glycosaminoglycan (GAG) mimetic derived from cellulose that promotes neurite extension over native GAGs, chondroitin sulfate-A (CS-A) and chondroitin sulfate-C (CS-C), which are present in neural ECM. Depending upon the degree and position of sulfation, the GAG mimetic can impact nerve growth factor binding and permissive neurite outgrowth. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Polyphosphates are important polyanionic electrolytes that play a major role in stabilization and consolidation of colloids surface and interior microstructures. In this study, the polyelectrolyte complexes (PEC) microcapsules (sodium cellulose sulfate-chitosan hydrochloride, sample 1), and the patched ones via sodium tripolyphosphate (sample 2), sodium pyrophosphate (sample 3) and sodium hexametaphosphate (sample 4) were fabricated under mild conditions. The effects of polyphosphates on the formation of the PEC microcapsules were investigated systematically. Scanning electron microscope (SEM) and confocal laser scanning microscope (CLSM) observation showed that both of the sample 2 and sample 3 had more compact interior microstructures with higher fluorescence intensity, compared with the sample 4 with macroporous ones and sample 1 with irregular ones. Fourier transform-infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA) showed the electrostatic interactions occurred among the –NH 3 + groups, –SO 3 − groups, HP 3 O 10 4− groups, P 2 O 7 4− groups and H 2 PO 4 − groups, and the sample 2 and sample 3 had a more thermal stability comparatively. The sample microcapsules showed good capacity of drug loading and encapsulation efficiency (max. 66.9 ± 4.6% and 74.2 ± 5.1%). In the in vitro release studies showed that the sample 2 and sample 3 had a larger accumulative drug release rate of 5-aminosalicylic acid (5-ASA) at the same time point and released completely at 12 h; the drug release mechanisms analysis indicated that the sample 1 and sample 3 were mainly diffusion controlled, while the sample 2 and sample 4 were followed the mechanism of non-Fickian transport. Under the polyphosphate's consolidation, the PEC microcapsules fabricated with sustained drug release profiles could be used as the promising drug vehicles. [ABSTRACT FROM AUTHOR]

For the first time, the synthesis of water-soluble copper-containing microcrystalline cellulose sulfates (Сu-MCS) has been performed by the ion exchange method. The composition of the products has been studied by chemical methods and X-ray spectral microanalysis. The copper content in the Сu-MCS samples was 12.6-14.1%. The absence of sodium in the resulting polymer indicates the complete substitution of the sodium cations by the copper cations in the sodium salt of MCC sulfate. The structure of the copper-containing sulfates of microcrystalline cellulose has been confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and electron paramagnetic resonance (EPR). According to the XRD method, Сu-MCS and Na-MCS have an amorphous structure in contrast to the original MCC samples, which have a high degree of crystallinity. The EPR data have demonstrated the formation of a pseudocrystalline structure of the copper-containing salt system in the Сu-MCS samples. As shown by atomic-force microscopy, the surface of the Сu-MCS films consists of homogeneous crystallites, which have a spherical or slightly extended form with the size of about 70 nm. The film surface is quite homogeneous in its phase composition and contains no impurities. [ABSTRACT FROM AUTHOR]

The deposition of polyelectrolyte (PEL) multilayers (PEMs) of poly(l-lysine)/cellulose sulfate (PLL/CS) onto germanium (Ge) substrates depending on salt concentration (cS) and deposition step z at constant PEL concentration cPEL = 0.01 M and pH = 7.0 was studied. In situ ATR-FTIR spectroscopy was used for the quantitative determination of alternate PLL/CS deposition profiles (adsorbed amount versus z) and total deposited PEM amount. By varying cS from 0 M to 1.0 M, a maximum of deposited amount was obtained at 0.1 M, so that both no salinity (0 M) and high salinity (1.0 M) revealed deposited amounts that were far lower than for mean salinity (0.1 M). Furthermore, in situ ATR-FTIR allowed to determine the detailed modulation of the PEL composition during the consecutive PEM deposition, which was interpreted as being due to both diffusion of given PEL from the PEM interior towards the outermost region and release of the PEM upon contact with the bulk oppositely charged PEL solution. Finally, ex situ ATR-FTIR measurements on the PEL solutions after deposition of PEM-20 revealed the distinct release of PEL from the PEM solely for cS = 1.0 M, due to the highest mobility of PEL under high salt conditions. These studies help to prepare functional PEM coatings with defined thicknesses and morphologies for the passivation and activation of material surfaces in the biomedical and food field.

The cellulose sulfate (CS) is a newly developed cellulose derivative. The work aimed to investigate the effect of oleic acid (OA) content on properties of CS-OA film. The process of oleic acid dispersion into film was described to evaluate its effect on the properties of the film. Among the formulations evaluated, the OA addition decreased the solubility and water vapor permeability of the CS-OA film. The surface contact angle changed from 64.2° to 94.0° by increasing CS/OA ratio from 1:0 to 1:0.25 (w/w). The TS increased with OA content below 15% and decreased with OA over 15%, but the ε decreased with higher OA content. The micro-cracking matrices and micro pores in the film indicated the condense structure of the film destroyed by the incorporation of oleic acid. No chemical interaction between the OA and CS was observed in the XRD and FTIR spectrum. Film formulation containing 2% (w/w) CS, 0.3% (w/w) glycerol and 0.3% (w/w) OA, showed good properties of mechanic, barrier to moisture and homogeneity.

Cellulose nanofibrils (CNF) were sulfonated and the dispersion quality was compared to unfunctionalized and 2,2,6,6-tetramethylpiperdine-1-oxyl radical (TEMPO) post-oxidation treatment of existing CNF (mechanically fibrillated pulp). A post-sulfonation treatment on existing CNF in chlorosulfonic acid and dimethylformamide (DMF) resulted in sulfonated CNF that retained a fibril-like morphology. There was a small decrease in the cellulose crystallinity index for the sulfonated CNF, but this was much lower than the reported regioselective oxidative bisulfite pretreatment method used to make sulfonated CNF. The current approach was extremely quick, and 5 min of reaction time was sufficient to result in significant improvements in dispersibility compared to unfunctionalized CNF. The sulfonated CNF and TEMPO oxidized CNF had better dispersibility compared to the unfunctionalized CNF when dispersed in DMF and water, and in many cases the sulfonated CNF had better dispersibility than the TEMPO CNF. It was found that when CNF was dispersed in DMF the TEMPO CNF formed carboxyl dimethylammonium groups, while the sulfonated CNF formed formate groups. [ABSTRACT FROM AUTHOR]

Angiogenesis plays an important role in both soft and hard tissue regeneration, which can be modulated by therapeutic drugs. If nanoparticles (NP) are used as vectors for drug delivery, they have to encounter endothelial cells (EC) lining the vascular lumen, if applied intravenously. Herein the interaction of unloaded polyelectrolyte complex nanoparticles (PECNP) composed of cationic poly(l-lysine) (PLL) and various anionic polysaccharides with human vascular endothelial cells (HUVEC) was analyzed. In particular PECNP were tested for their cell adhesive properties, their cellular uptake and intracellular localization considering composition and net charge. PECNP may form a platform for both cell coating and drug delivery. PECNP, composed of PLL in combination with the polysaccharides dextran sulfate (DS), cellulose sulfate (CS) or heparin (HEP), either unlabeled or labeled with fluorescein isothiocyanate (FITC) and either with positive or negative net charge were prepared. PECNP were applied to human umbilical cord vein endothelial cells (HUVEC) in both, the volume phase and immobilized phase at model substrates like tissue culture dishes. The attachment of PECNP to the cell surface, their intracellular uptake, and effects on cell proliferation and growth behavior were determined. Immobilized PECNP reduced attachment of HUVEC, most prominently the systems PLL/HEP and PLL/DS. A small percentage of immobilized PECNP was taken up by cells during adhesion. PECNP in the volume phase showed no effect of the net charge sign and only minor effects of the composition on the binding and uptake of PECNP at HUVEC. PECNP were stored in endosomal vesicles in a cumulative manner without apparent further processing. During mitosis, internalized PECNP were almost equally distributed among the dividing cells. Both, in the volume phase and immobilized at the surface, PECNP composed of PLL/HEP and PLL/DS clearly reduced cell proliferation of HUVEC, however without an apparent cytotoxic effect, while PLL/CS composition showed minor impairment. PECNP have an anti-adhesive effect on HUVEC and are taken up by endothelial cells which may negatively influence the proliferation rate of HUVEC. The negative effects were less obvious with the composition PLL/CS. Since uptake and binding for PLL/HEP was more efficient than for PLL/DS, PECNP of PLL/HEP may be used to deliver growth factors to endothelial cells during vascularization of bone reconstitution material, whereas those of PLL/CS may have an advantage for substituting biomimetic bone scaffold material.

Flocculants are widely used along with coagulant to increase the efficiency of coagulation-flocculation process for removal of colloidal particles from wastewaters. The most widely used flocculants are synthetic which have some problems such as non-biodegradability and release of toxic residual monomers. The main aim of this study is to evaluate the performance of cellulose sulfate (CS), which was synthesized through sulfonation of cotton, as a biodegradable and natural-based flocculant. Reaction time as an important factor in the sulfonation reaction was optimized for obtaining CS with high charge density and suitable fiber size. The sulfate content, charge density (CD) and morphology of each CS were determined to investigate and select the best CS for the flocculation process. A suspension containing kaolin clay was used as a colloidal test solution and coagulation was performed using alum (as a coagulant) and CS (as a flocculant). Optimization was performed using response surface methodology (RSM). The optimization results showed that CS had a good performance in turbidity reduction in coagulation-flocculation treatment and maximum turbidity reduction (98.9%) was obtained at alum dosage of 23.1 mg/L, CS dosage of 7.2 mg/L and pH 6.2. The results showed that the pH variation had insignificant effect on the CS dosage. Zeta potential measurements and microscopic photos of flocs confirm charge neutralization and bridge formation in flocculation using cellulose sulfate, respectively. Also, the total chemical consumption reduced compared with the use of alum alone. As a consequence, CS can be considered as a suitable alternative for conventional flocculants. [ABSTRACT FROM AUTHOR]

Cellulose sulfate film with antimicrobial properties was prepared by incorporating β-cyclodextrin (β-CD) and mustard essential oil (MO). The effects of MO concentration on mechanical and barrier properties of films were evaluated and compared with control one (without MO). The addition of MO increased the elongation of the film, reduced the tensile strength, the Young's modulus and the water sorption, but did not significantly affect the water vapor permeability of the film. The results can be partly explained by analysis of SEM, XRD and FTIR. More important, films with MO showed great antimicrobial activity against Escherichia coli , Staphylococcus aureus , and lower for Bacillus subtilis and Aspergillus niger . Films incorporated with β-CD reduced the loss of MO in the preparation and preservation of films according to the MO left in the films, which indicated slow release of MO. The MO content in NaCS-β-CD-MO films was 11 mg/g, while was 7 mg/g in NaCS-MO films prepared under the same conditions. The results of the present study suggest that MO as a natural antibacterial agent and β-CD as a carrier of slow release can potentially be used in edible film or coating for packaging a wide range of microbial sensitive food products. [ABSTRACT FROM AUTHOR]

Experiments on rabbits showed that increasing the dose of intravenously administered cellulose sulfate from wheat straw (dynamic viscosity 3.4 cP, sulfur content 14.1%) increased plasma clotting time in some coagulation tests and plasma anticoagulant activity. When cellulose sulfate was administered in the dose of 1 mg/kg, plasma clotting time in the presence of the anticoagulant (5 min after administration) was ~3-fold higher than after saline administration. [ABSTRACT FROM AUTHOR]

Polysaccharide sulfates are naturally existing chemicals that show important biological activities in living organisms. Cellulose sulfate is a semi-synthesized polysaccharide sulfate with a relatively simple chain structure and unique biological properties and its biological applications have been explored in research and clinical trials. With the advance of cellulose derivatization and characterization, cellulose sulfate molecules with tailored structures have been developed to fulfill individual requirements. This review aims to provide a summary of recent development of cellulose sulfate in biomedical applications. Its synthesis pathways were discussed with structure–property relationship elucidated. The application of cellulose sulfate in drug delivery and microbe/cell immobilization were summarized with emphasis given on its polyelectrolyte complex formation processes. [ABSTRACT FROM AUTHOR]

Here, we report fabrication of polyelectrolyte multilayers by blending a natural glycosaminoglycan (heparin) with semisynthetic cellulose sulfates as polyanions paired with polycation chitosan. Two types of polyanionic blends were prepared by mixing heparin with either cellulose sulfates (CS) of high (CS2.6) or intermediate (CS1.6) sulfation degree in equal mass ratios. Multilayer growth was monitored by surface plasmon resonance (SPR) and quartz crystal micro balance with dissipation monitoring (QCM-D) where as surface wettability was measured by water contact angle measurements (WCA). Both SPR and QCM-D showed differences in biomolecular mass adsorption and dissipation values for different multilayers and also helped in estimating the hydration levels of layers. WCA indicated arrangement of polyanion and polycation layers within the multilayer systems, weather distinct layers, or more intermingled multilayers were established. Overall physico-chemical characterization data suggested a dominating incorporation of heparin over CS in blend multilayer systems. Biological interactions of these blend multilayers investigated with C2C12 cells also indicated a leading contribution of heparin in the blend systems. This current study suggested that heparin was preferentially incorporated over CS that are highly sulfated and points towards the dominance of carboxylic groups over sulfate groups in interacting with amino groups of chitosan. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 4224-4233, 2014. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fabrication of multilayers with three different sulfated polyanions paired with chitosan. [•] Use of semi-synthetic cellulose sulfates as replacement of heparin in multilayers. [•] Study on effects of polyanions chemical composition on layer properties and bioactivity. [•] Distinct differences in multilayer properties and cell behaviour were achieved. [Copyright &y& Elsevier]

Abstract: Novel edible films prepared from cellulose sulfate (CS) and glycerol by casting film-solution on leveled trays were characterized in this research. The dense CS films with ordered microstructure were transparent, homogenous, flexible, water-soluble and resistant to oils and fats. The CS molecular weight and glycerol content affected mechanical properties and water vapor permeability of CS film. The tension strength (TS) of CS film prepared from high MW (η 2% = 907, 2% aqueous solutions viscosity) could reach 60.27 MPa, at which the elongation at break (EAB) of CS film was 15.88%. Increasing the molecular weight of CS could improve the TS and EAB, while addition of glycerol would decrease the TS. Furthermore, the addition of glycerol and increasing CS molecular weight could decrease the WVP down to values about 3.7 × 10−11 g m−1 s−1 Pa−1, which revealed that the vapor barrier performance of CS film could be regulated by CS molecular weight and glycerol content. The CS based coating could extend the shelf life of bananas. Therefore, cellulose sulfate could be used as potential degradable coating materials in food packaging. [Copyright &y& Elsevier]

Synthesis of cellulose sulfates (CSs) and carboxyl cellulose sulfates (COCSs) with regioselectively or regiospecifically distributed functional groups within anhydroglucose units was reported. CS with regioselectively distributed sulfate groups at 2,3- O- or 2,6- O-position were homogeneously synthesized and cellulose trifluoroacetate (CTFA) was used as intermediates. The trifluoroacetyl groups were detected primarily at 6- O-position and their distributions could be altered by changing the amount of trifluoroacetyl anhydride (TFAA). Various sulfating agents were used for further homogeneous sulfation of CTFA. The total degree of sulfation (DS) and the distribution of sulfate groups within the repeating units were affected by the amount of TFAA, the type and amount of sulfating agents. Subsequent homogenous 4-acetamide-TEMPO or TEMPO-mediated oxidation of CS led to COCS with carboxyl groups regiospecifically distributed at C6 position, which may be interesting structural mimics for natural occurring heparin. [ABSTRACT FROM AUTHOR]

Highlights: [•] Sulfuric acid/ethanol was successfully used as sulfating agent to prepare CS. [•] Water in system was removed to decrease the hydrolysis by adding Na2SO4. [•] The conditions on the sulfating process were investigated in detail. [ABSTRACT FROM AUTHOR]

Rabbit plasma coagulation time in the APTT and ReaClot-heparin tests, antithrombin and anti-factor Xa activities of plasma, and the effective half-life and duration of action increase with dose (0.3 to 10 mg/kg, i.v.) of injected cellulose sulfate (molecular weight 10 - 30 kDa, degree of sulfonation 1.8, antithrombin activity 130 ± 12 IU/mg, anti-factor Xa activity 45 ± 3.3 IU/mg). Cellulose sulfate independently neither influences human platelet aggregation nor potentiates adenosinediphosphate-induced human platelet aggregation and fibrinolytic activity of plasma euglobulin fraction in vivo but it favors an increase in the fibrinolytic activity of plasma upon intravenous injection in rabbits. [ABSTRACT FROM AUTHOR]

Abstract: Synthetic biology has been successfully used to program novel metabolic function in mammalian cells and to design the first-generation of prosthetic networks that have shown the potential for the treatment of obesity, hormone-related disorders and hyperuricemia in small-animal model systems. By functionally rewiring luteinizing hormone receptor signaling to CREB1 (cAMP-responsive element binding protein 1)-mediated transgene expression via the common cyclic adenosine monophosphate (cAMP) second messenger pool we have designed an artificial insemination device which enables lutropin-triggered in-utero release of sperms protected inside cellulose-based implants. Swiss dairy cows treated with such in-utero implants containing spermatozoa and mammalian cells transgenic for luteinizing hormone receptor and CREB1-inducible expression of an engineered cellulase showed ovulation-triggered implant degradation and sperm release leading to successful fertilization of the animals. Synthetic devices plugged into endogenous control circuitry enable the body to automatically control spatio-temporal metabolic activities that could improve the economics of cattle breeding and provide novel opportunities for future therapeutic interventions. [Copyright &y& Elsevier]

Abstract: The synthesis and characterisation of cellulose sulfates were reported. Various cellulose sulfates with diverse degrees of substitution ascribed to sulfate groups (DSS) between 0.21 and 2.59 were prepared through acetosulfation or direct sulfation of two celluloses. The number-average degrees of polymerisation (DP n ) of these cellulose sulfates were determined to be in the range of 59 and 232 via size exclusion chromatography (SEC). Accordingly, the molecular weight of cellulose was remarkably decreased during the sulfation. The use of high amount of sulfating agent and high sulfation temperature led to stronger reduction of the DP n in comparison to low amount of sulfating agent and low temperature. The morphology of cellulose sulfate was analysed via scanning electron microscopy (SEM) and wide-angle X-ray diffraction (WAXD). Obtained cellulose sulfates demonstrated different surface properties from cellulose and became more amorphous than starting celluloses. [ABSTRACT FROM AUTHOR]

Abstract: Both sulfate and carboxyl groups are found in many glycosaminoglycans exhibiting diverse biological activities, such as heparin. Present study reports on the preparation of cellulose derivatives containing both sulfate and carboxyl groups that were regioselectively introduced into anhydroglucose units (AGU) of cellulose. The products – carboxyl cellulose sulfates (COCS) – with various contents of both functional groups were obtained by two synthesis routes. One way started with sulfation of cellulose yielding cellulose sulfate (CS) and was followed by TEMPO-mediated oxidation of CS. In another way, cellulose at first underwent TEMPO-mediated oxidation yielding carboxyl cellulose (COC). Subsequently, acetosulfation of the COC was carried out. The products were characterized by diverse analysis methods, and the amounts of both functional groups in CS, COC and COCS were determined. Finally, the biological activity of COCS was examined. [Copyright &y& Elsevier]

FT Raman investigation of sodium cellulose sulfates (NaCS) was reported. Different NaCS were prepared by two diverse sulfation methods and their total degrees of substitution (DS) of sulfate groups were determined through either 13C-NMR spectroscopy or elemental analysis. Subsequently, these NaCS were characterized with FT Raman spectroscopy. The caused bands through the introduction of the sulfate groups in cellulose chain were explained and assigned. Additionally, a strong linear correlation between the areas under the bands ascribed to the stretching vibrations of C–O–S groups and the total DS of NaCS was presented. A rapid method of quantifying the total DS of NaCS was established. Finally, sodium sulfate (Na2SO4), a salt that is very often produced during the sulfation of cellulose, was found to be analyzable even with a weight content of 0.12% in NaCS. The method of quantifying the content of this salt in NaCS was investigated with Raman spectroscopy. [ABSTRACT FROM AUTHOR]

We have investigated the proton conductivity, solvent uptake, and the methanol permeability coefficient (PM) in aqueous methanol solutions of the cellulose sulfate (CS) electrolyte membranes which were prepared by sulfating regenerated cellulose membranes. The proton conductivity of the CS membranes is enhanced with increasing number of sulfate groups. Solvent uptake and PM for the CS membranes are almost independent of methanol content, and the CS membranes with higher solvent uptake show higher PM. The introduction of cross-linkage into the CS membranes not only enhances the proton conductivity but also decreases the methanol permeability because of a considerable reduction in solvent uptake. The cross-linked CS membranes exhibit a proton conductivity of 0.081 S cm-1 at room temperature, which is comparable to that of Nation 112®. The methanol permeability measured by using a 3 M methanol solution is less than half, compared with Nation 112®. [ABSTRACT FROM AUTHOR]

Abstract: Technologies currently available for the controlled release of protein therapeutics involve either continuous or tissue-specific discharge from implants or engineered extracellular matrix mimetics. For some therapeutic applications the trigger-controlled release of protein cargo from a synthetic implant could be highly desirable. We have designed the CellEase technology, a two-component system consisting of cellulose sulfate (CS) poly-diallyldimethyl ammonium chloride (pDADMAC) capsules harboring mammalian sensor cells transgenic for trigger-inducible expression of an engineered secreted mammalian cellulase (SecCell). SecCell is a Bacillus subtilis-derived (1–4)-β-glucanase, which was modified by replacing the N-terminal part of the bacterial enzyme with a murine Igκ-chain V-12-C region-derived secretion signal. SecCell was engineered for doxycycline- or erythromycin-inducible expression to enable trigger-controlled secretion by mammalian cells. Detailed characterization of SecCell showed that it was glycosylated and efficiently secreted by a variety of mammalian sensor cells such that it could internally rupture CS-pDADMAC capsules within which the cells had been encapsulated. When SecCell was inducibly expressed in sender cells, that were co-encapsulated with producer cell lines expressing therapeutic proteins, the removal of relevant inducer molecules enabled the time-dependent discharge of these therapeutic proteins, the kinetics of which could be modified by varying the concentration of inducer molecules or the amount of encapsulated sender cells. SecCell''s capacity to rupture CS-pDADMAC capsules exclusively internally also enabled the independent trigger-induced release of different proteins from two capsule populations harboring different inducible SecCell sensor cells. CellEase-based protein release was demonstrated in vivo using capsules implanted intraperitoneally into mice that enabled the doxycycline-controlled release of a model glycoprotein and accumulation in the bloodstream of treated animals. Trigger-induced breakdown of tissue-compatible implants which provide a timely controlled release of biologics may foster novel opportunities in human therapy. [Copyright &y& Elsevier]

Abstract: Background: Six percent cellulose sulfate (CS) is a vaginal gel that has been in development as a microbicide. Study Design: This was a single-center, multi-dose, Phase I, placebo-controlled, randomized, fully masked study conducted in Yaoundé, Cameroon, and involving sexually active women at low risk for sexually transmitted infections (STIs). Methods: The study assessed the effect of CS and K-Y® Jelly applied vaginally four times per day, for 14 consecutive days, on genital epithelial disruption, candidiasis and bacterial vaginosis (BV). Acceptability of the products was also assessed. Twenty-seven women were enrolled in each treatment group. Results: Two (7.4%) of the women in each group developed genital epithelial disruption. One (3.7%) of the women in each group developed candidiasis, and one (3.7%) of the K-Y users developed BV. One (3.7%) of the CS users said she would not buy her product for pregnancy prevention but would for STI prevention. All the remaining women indicated they would buy their product for both indications. Conclusion: The results suggest that the safety and acceptability of 6% CS gel are comparable to that of K-Y Jelly. [Copyright &y& Elsevier]

Adhesion of Plasmodium falciparum infected erythrocytes (IE) to placental chondroitin-4-sulfate (CSA) has been linked to the severe disease outcome of pregnancy-associated malaria. Consequently, sulfated polysaccharides with inhibitory capacity may be considered for therapeutic strategies as anti-adhesive drugs. During in vitro screening a regioselectively modified cellulose sulfate (CS10) was selected as prime candidate for further investigations because it was able to inhibit adhesion to CSA expressed on CHO cells and placental tissue, to de-adhere already bound infected erythrocytes, and to bind to infected erythrocytes. Similar to the undersulfated placental CSA preferred by placental-binding infected erythrocytes, CS10 is characterized by a clustered sulfate pattern along the polymer chain. In further evaluation of its effects on P. falciparum interactions with host erythrocytes, we now show that CS10 inhibits the in vitro asexual growth of parasites in erythrocytes. Furthermore, we show that CS10 interferes with C1 of the classical complement pathway but not with MBL of the lectin pathway. In order to gain insights into the possible interactions of CS10 with known parasite receptors at the molecular level, we designed 3D-structures of characteristic stretches of CS10. CS10 fragments with clustered sulfate groups showed complex patterns of hydrophobic and hydrophilic patches most likely suitable for interactions with protein binding partners. The significance of CS10 interactions with the complement system as well as its anti-malarial effect for prospective drug application are discussed. [ABSTRACT FROM AUTHOR]

Abstract: A whole-cell epoxide-hydrolyzing biocatalyst designed as uniform polyelectrolyte complex capsules was developed. Nocardia tartaricans bacterial cells with cis-epoxysuccinate (CES) hydrolase activity were used as a model microbial strain. Stereospecific hydrolysis of CES catalyzed by CES hydrolase in encapsulated cells yields enantiomerically pure l-(+)-tartrate. An air-stripping device with multiloop reactor was used for controlled production of capsules containing bacterial cells with the standard deviation in diameter below 4% and in membrane thickness below 7%. Capsules formed by polyelectrolyte complexation of sodium alginate and cellulose sulfate as polyanions, poly(methylene-co-guanidine) as polycation, CaCl2 and NaCl (SA-CS/PMCG) provide a favorable microenvironment for encapsulated cells. Biotransformation was monitored by RP-HPLC, electrospray ionization mass spectrometry and optical rotation. The results are discussed in view of data previously obtained by cell entrapment in hardened calcium pectate gelled beads (CPG). Encapsulation of the whole-cell biocatalyst in SA-CS/PMCG capsules leads to (i) about two-fold increase, from 91.5 to 208.2U/mg, in the CES hydrolase activity, (ii) a decreased time required for total biotransformation, from 5.5 to 3h, and (iii) a significantly improved relative increase in CES hydrolase activity during 51 days of storage, from about 3-fold to about 20-fold, compared to the CPG beads. [Copyright &y& Elsevier]