Antimicrobial ion-imprinted chitosan-derived hydrogel with quaternary ammonium and thermoresponsive components for UO22+ adsorption.

Uranium recovery from wastewater or seawater is important for both pollution control and uranium supply. Due to the complexity of the water body, it requires that the adsorbent should not only be highly efficient for selective adsorption but also have good antimicrobial properties. In this study, an antimicrobial thermosensitive hydrogel (UITAC) for uranium adsorption was prepared by one-step ion-imprinted polymerization using chitosan as a substrate and allyl trimethylammonium chloride as the antimicrobial modifier. UITAC showed excellent antibacterial rate against Escherichia coli and Staphylococcus aureus, being 98.8 % and 89.1 %, respectively. Endothermic and exothermic peaks respectively showed up at 36.3-38.5 °C and 30.5-34.1 °C in the DSC curves. UITAC quickly achieved its adsorption equilibrium in 30.0 min at 50 °C, pH 5.0 in the 0.8 mg/mL UO22+ solution, with an adsorption capacity of 81.2 mg/g. The adsorption capacity could remain at 80 % after 5 cycles of repeated use. UITAC showed better adsorption selectivity to UO22+ than vanadium and other metal ions, with selectivity coefficients α(UO22+/Mn+) being 1.4-10.3. The pseudo-second-order kinetics and Langmuir adsorption model had a better fit for UO22+ adsorption by UITAC. The adsorption was a spontaneous process. The Gibbs Free Energy change, enthalpy change, and entropy change at 323.2 K were - 16.0 kJ/mol, 64.3 kJ/mol, and 248.4 J/mol·K, respectively. UITAC showed high potential in practical application environment.

White light powered antimicrobial nanoagents for triple photothermal, chemodynamic and photodynamic based sterilization.

Antibacterial nanoagents have been increasingly developed due to their favorable biocompatibility, cost-effective raw materials, and alternative chemical or optical properties. Nevertheless, there is still a pressing need for antibacterial nanoagents that exhibit outstanding bacteria-binding capabilities and high antibacterial efficiency. In this study, we constructed a multifunctional cascade bioreactor (GCDCO) as a novel antibacterial agent. This involved incorporating carbon dots (CDs), cobalt sulfide quantum dots (CoSx QDs), and glucose oxidase (GOx) to enhance bacterial inhibition under sunlight irradiation. The GCDCO demonstrated highly efficient antibacterial capabilities attributed to its favorable photothermal properties, photodynamic activity, as well as the synergistic effects of hyperthermia, glucose-augmented chemodynamic action, and additional photodynamic activity. Within this cascade bioreactor, CDs played the role of a photosensitizer for photodynamic therapy (PDT), capable of generating ˙O2- even under solar light irradiation. The CoSx QDs not only functioned as a catalytic component to decompose hydrogen peroxide (H2O2) and generate hydroxyl radicals (˙OH), but they also served as heat generators to enhance the Fenton-like catalysis process. Furthermore, GOx was incorporated into this cascade bioreactor to internally supply H2O2 by consuming glucose for a Fenton-like reaction. As a result, GCDCO could generate a substantial amount of reactive oxygen species (ROS), leading to a significant synergistic effect that greatly induced bacterial death. Furthermore, the in vitro antibacterial experiment revealed that GCDCO displayed notably enhanced antibacterial activity against E. coli (99+ %) when combined with glucose under simulated sunlight, surpassing the efficacy of the individual components. This underscores its remarkable efficiency in combating bacterial growth. Taken together, our GCDCO demonstrates significant potential for use in the routine treatment of skin infections among diabetic patients.

"One-pot" preparation and adsorption performance of chitosan-based La3+/Y3+ dual-ion-imprinted thermosensitive hydrogel.

Temperature-sensitive materials are increasingly of deep interest to researchers. Ion imprinting technology is widely used in the field of metal recovery. In order to solve the problem of rare earth metal recovery, we designed a temperature-sensitive dual-imprinted hydrogel adsorption product (CDIH) with chitosan as the matrix, N-isopropylacrylamide as a thermally responsive monomer, and La3+ and Y3+ as the co-templates. The reversible thermal sensitivity and ion-imprinted structure were determined by differential scanning calorimetry, Fourier transform infrared spectrometer, Raman spectra, Thermogravimetric analysis, X-ray photoelectron spectroscopy, Scanning electron microscopy and X-ray energy spectroscopy various characterizations and analyses. The simultaneous adsorption amount of CDIH for La3+ and Y3+ was 87.04 mg/g and 90.70 mg/g, respectively. The quasi-secondary kinetic model and Freundlich isotherms model well described the adsorption mechanism of CDIH. It's worthy to mention that CDIH could be well regenerated through washing with deionized water at 20 °C, with a desorption rate of 95.29 % for La3+ and 96.03 % for Y3+. And after 10 cycles of reuse, 70 % of the adsorption amount could be maintained, revealing excellent reusability. Furthermore, CDIH expressed better adsorption selectivity to La3+ and Y3+ than its non-imprinted counterparts in a solution containing six metal ions.

Pb2+-imprinted thermosensitive antibacterial adsorbent derived from sodium alginate and PNIPAM for Pb2+ recovery.

Two sodium alginate-based Pb2+-imprinted thermosensitive hydrogels (SPIT (without ɛ-PL) and SPPIT (with ɛ-PL)) were synthesized, with sodium alginate and ɛ-polylysine (ɛ-PL) as the matrix, N-isopropylacrylamide as the monomer. Characterization with differential scanning calorimeter, Fourier transform infrared spectroscopy, thermogravimetric analyzer, scanning electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy confirmed the aimed structure of the hydrogels. The adsorption capacity of SPIT and SPPIT for Pb2+ was 98.64 mg/g and 153.49 mg/g, respectively. Washing the Pb2+-loaded adsorbent with 10 °C deionized water, SPIT and SPPIT achieved a desorption efficiency of 94.59 % and 97.51 %, respectively. After 10 cycles of adsorption-desorption process, the adsorption capacity and desorption efficiency remained at about 80-88 % of the original ones, expressing excellent reusability. In a mixture containing eight metal ions (Pb2+, Cu2+, Mg2+, Ca2+, Cd2+, Na+, K+, Fe3+), the adsorption capacity of SPIT to Pb2+ was 92.49 mg/g, and that of SPPIT was 102.49 mg/g, much higher than that to the other ions (1.50-11.38 mg/g on SPIT, 9.48-27.45 mg/g on SPPIT), showing excellent adsorption selectivity. The introduction of ɛ-PL enhanced the adsorption capacity, antibacterial ability and stability of the hydrogel, ensuring better application potential in real wastewater.

Electrospinning membranes with Au@carbon dots: Low toxicity and efficient antibacterial photothermal therapy.

As bacterial infections continue to pose a significant challenge to healthcare globally, new therapeutic strategies, interventions, and complementary approaches that address both infection prevention and treatment are needed. As one such strategy, photothermal therapy (PTT) as a non-chemotherapeutic approach is considered a safe and potentially efficient strategy to combat bacterial infections, particularly for antibiotic-resistant pathogens given that PTT operates via a temperature-dependent process against which the development of bacterial resistance is unlikely. Here, we prepared Au@CDs composite nanoparticles (Au@CD) comprised of gold nanoparticles (AuNPs) and carbon dots (N,S-CDs), and investigated their use as a photothermal agent in PTT. The presence of the CDs as surface decorations conferred improved photothermal conversion efficiency, photostability, and biocompatibility to the Au@CD when compared to the parent AuNPs. To investigate if the Au@CD could serve as a PTT wound dressing and accelerate tissue repair, they were embedded within a PVA membrane via electrospinning. The resultant Au@CD membrane exhibited excellent biocompatibility and photothermal antimicrobial activity. In vitro photothermal antibacterial inactivation studies confirmed their efficacy against S. aureus and E. coli (99 + % inactivation of both pathogens under NIR irradiation). Moreover, in vivo studies employing Kunming male mice with S. aureus-infected wounds on their backs were chosen as a trauma model, with the Au@CD membranes serving as wound dressings. The results showed that a local temperature increased up to 50 °C upon NIR irradiation could effectively eradicate bacteria at the wound site, reduce the risk of bacterial infection, suppress inflammation as well as improve collagen deposition and angiogenesis, all of which together facilitated wound closure and resulted in a better therapeutic effect than the controls. Taken together, this work confirms that NIR-irradiated Au@CD-based membranes and related materials are promising photothermal antimicrobial platforms for wound dressings and related healthcare applications.

Water-Recyclable Chitosan-Based Ion-Imprinted Thermoresponsive Hydrogel for Rare Earth Metal Ions Accumulation.

The demand for rare earth metal increases rapidly in the modern high-tech industry and therefore the accumulation of rare earth metal ions from an aqueous environment becomes a significant concern worldwide. In this paper, a water-recyclable chitosan-based La3+-imprinted thermoresponsive hydrogel (CLIT) was prepared to accumulate La3+ from solution. The CLIT was characterized by DSC, FITR, Raman spectroscopy, XPS, and SEM, which revealed obvious reversible thermosensitivity and imprinted sites of La3+ ions. An adsorption capacity of 112.21 mg/g to La3+ ions was achieved on CLIT under its optimum adsorption conditions (pH 5, 50 °C, 60 min). The adsorption could be well illustrated by second-order kinetics and Freundlich isotherm models. The La3+-adsorbed CLIT could be recycled only by rinsing with 10 °C cold water, with a desorption rate of 96.72%. After ten cycles of adsorption-desorption, CLIT retained good adsorption capability. In the solution containing six ions, the adsorption coefficients kLa3+/Mn+ of CLIT were 2.04-3.51 times that of non-imprinted hydrogel, with kLa3+/Y3+, kLa3+/Gd3+, kLa3+/Al3+, kLa3+/Fe3+ and kLa3+/Cu2+ being 1.67, 2.04, 3.15, 2.72 and 4.84, respectively.

Dual photothermal nanocomposites for drug-resistant infectious wound management.

Management of antibiotic-resistant bacteria-induced skin infections for rapid healing remains a critical clinical challenge. Photothermal therapy, which uses mediated hyperthermia to combat such problems, has recently been recognised as a promising approach to take. In this study, bacterial cellulose-based photothermal membranes were designed and developed to combat bacterial infections and promote rapid wound healing. Polydopamine was incorporated into gold nanoparticles to produce superior dual-photothermal behaviour. The in vitro antibacterial efficacy of the prepared composite membranes against S. aureus, E. coli and methicillin-resistant Staphylococcus aureus (MRSA) could reach 99% under near-infrared (NIR) irradiation. In addition, the synthesised nanocomposite exhibited good biocompatibility in vitro as demonstrated by a cell survival ratio of >85%. The effectiveness of the composite membranes on wound healing was further investigated in a murine model of MRSA-infected wounds, focusing on the effect of photothermal temperature. According to the detailed therapeutic mechanism study undertaken, the composite membranes cause bacterial killing initially and promote the transition from the inflammatory phase to proliferation by suppressing pro-inflammatory cytokine production, promoting collagen deposition, and stimulating angiogenesis. Considering their remarkable effectiveness and facile fabrication process, it is expected that these novel materials could serve as competitive multifunctional dressings in the management of infectious wounds and accelerate the regeneration of damaged tissues related to abnormal immune responses.

Cassava Starch-Based Thermo-Responsive Pb(II)-Imprinted Material: Preparation and Adsorption Performance on Pb(II).

Heavy metal pollution is currently an increasing threat to the ecological environment, and the development of novel absorbents with remarkable adsorption performance and cost-effectiveness are highly desired. In this study, a cassava starch-based Pb(II)-imprinted thermo-responsive hydrogel (CPIT) had been prepared by using cassava starch as the bio-substrate, N-isopropyl acrylamide (NIPAM) as the thermo-responsive monomer, and Pb(II) as the template ions. Later, a variety of modern techniques including FTIR, DSC, SEM, and TGA were employed to comprehensively analyze the characteristic functional groups, thermo-responsibility, morphology, and thermal stability of CPIT. The obtained material exhibited superior performance in adsorption of Pb(II) and its maximum adsorption capacity was high-up to 114.6 mg/g under optimized conditions. Notably, the subsequent desorption (regeneration) process was fairly convenient by simply rinsing with cold deionized water and the highest desorption efficiency could be achieved as 93.8%. More importantly, the adsorption capacity of regenerated CPIT still maintained 88.2% of the value of starting material even after 10 recyclings. In addition, the excellence of CPIT in selective adsorption of Pb(II) should also be highlighted as its superior adsorption ability (97.9 mg/g) over the other seven interfering metal ions.

Bioadsorbents from algae residues for heavy metal ions adsorption: chemical modification, adsorption behaviour and mechanism.

Biosorption is an emerging technology for the removal of heavy metals from industrial wastewater by natural or modified biomass. In this study, we proposed a novel protocol for making full use of seaweeds. Brown seaweed Sargassum carpophyllum residue (SCR) and green seaweed Caulerpa lentillifera residue (CLR) were obtained after extraction of the bioactive polysaccharides. The obtained residues were further chemical modified by butanedioic anhydride to obtained respective carboxylated product, named CSCR and CCLR. According to the titration results, CSCR and CCLR contained 2.77 and 2.12 mmol/g of carboxyl group. After modification, the adsorption capacity for metal ions increased by 3-6 times. The adsorption capacity of CSCR for Cu2+, Pb2+, Cd2+ and Mn2+ was 52.37, 107.11, 85.62, and 43.52 mg/g, and that of CCLR was 78.10, 108.80, 87.30 and 57.80 mg/g, respectively. The adsorption was well described by the pseudo-second-order kinetic model and Langmuir adsorption isotherm equation.

Polysaccharide from Caulerpa lentillifera: extraction optimization with response surface methodology, structure and antioxidant activities.

Ultrasonic-assisted extraction based on Response Surface Methodology was applied to isolate a polysaccharide (CLP) from Caulerpa lentillifera obtained in the South China Sea and the highest yield of the crude polysaccharide was 11.8%. CLP consisted of xylose, galactose, glucose and glucuronic acid in a molar ratio of 2.00: 1.00: 0.26: 0.04, with a molecular weight of 115 kDa. The content of uronic acids and sulfate groups in CLP was 14.10% and 27.40%, respectively. CLP presented good radical scavenging activities against O2·-, DPPH radical, while the scavenging activities against OH· and ABTS radical were not so satisfying.

Ion-imprinted thermosensitive chitosan derivative for heavy metal remediation.

Ion-imprinted thermosensitive chitosan derivative (ITC) was successfully synthesized through a novel gradient heating process towards applications in heavy metal remediation, using Cu2+ template paired with N-isopropylacrylamide (NIPAM) monomer. SEM, DSC, FTIR and Raman spectroscopy were used to characterize the structure and properties of ITC. The phase change temperature (PCT) of ITC was 35.31 °C in the heating cycle, whereas in the cooling cycle the PCT for ITC was 26.27 °C. The adsorption capacity of ITC for Cu2+ at 45 °C (> PCT) was 88.94 mg/g. Desorption rate of 98.90 % was achieved after washing with ultra-pure water at 20 °C (< PCT). An adsorption capacity of 85 mg/g and a desorption rate of 97 % sustained after five cycles reuse. The adsorption capacity for Cu2+ was measured at 80.23 mg/g under other seven interfering metal ions. The adsorption kinetics and adsorption isotherm fitted pseudo-second-order and Langmuir equation, respectively.

Cellulose Nanofiber-Reinforced Ionic Conductors for Multifunctional Sensors and Devices.

Ionic conductors are normally prepared from water-based materials in the solid form and feature a combination of intrinsic transparency and stretchability. The sensitivity toward humidity inevitably leads to dehydration or deliquescence issues, which will limit the long-term use of ionic conductors. Here, a novel ionic conductor based on natural bacterial cellulose (BC) and polymerizable deep eutectic solvents (PDESs) is developed for addressing the abovementioned drawbacks. The superstrong three-dimensional nanofiber network and strong interfacial interaction endow the BC-PDES ionic conductor with significantly enhanced mechanical properties (tensile strength of 8 × 105 Pa and compressive strength of 6.68 × 106 Pa). Furthermore, compared to deliquescent PDESs, BC-PDES composites showed obvious mechanical stability, which maintain good mechanical properties even when exposed to high humidity for 120 days. These materials were demonstrated to possess multiple sensitivity to external stimulus, such as strain, pressure, bend, and temperature. Thus, they can easily serve as supersensitive sensors to recognize physical activity of humans such as limb movements, throat vibrations, and handwriting. Moreover, the BC-PDES ionic conductors can be used in flexible, patterned electroluminescent devices. This work provides an efficient strategy for making cellulose-based sustainable and functional ionic conductors which have broad application in artificial flexible electronics and other products.

Synergistic regulation of osteoimmune microenvironment by IL-4 and RGD to accelerate osteogenesis.

The control of early inflammatory reactions and recruitment of progenitor cells are critical for subsequent tissue repair and regeneration after biomaterial implantation. The aim of this study was to design a multi-functional biomaterial with a controlled drug delivery system to create an optimal local environment for early osteogenesis. Here, the anti-inflammatory cytokine IL-4 and pro-osteogenic RGD peptide were assembled layer-by-layer on TiO2 nanotubes. A poly(dopamine) (DOP) coating was employed onto TiO2 nanotubes (T/DOP) to functionalized with IL-4 (T/DOP-IL4). Then, a carboxymethyl chitosan hydrogel layer (CG) was generated on T/DOP-IL4 to control IL-4 release and RGD peptide immobilization. Cell co-culture models were applied to study macrophage polarization on various material surfaces and the regulation of mesenchymal stromal cell (MSC) osteogenic differentiation. Our data suggest that T/DOP-IL4/CG-RGD surfaces developed in this study are multi-functional, and can not only drive phenotypic changes in macrophages (switching to anti-inflammatory M2 phenotype), resulting in the production of reparative cytokines such as IL-10, but also enhance MSC differentiation related to the activation of BMP/SMAD/RUNX2 signaling. This study further confirmed that the introduction of anti-inflammatory cytokine (IL-4) and cell adhesive motif (RGD) onto Ti substrate can work synergistically to generate a more favorable early-stage osteo-immune environment with superior osteogenic properties, thus representing a potential ideal surface for the generation of bone biomaterials.

Dansyl-modified carbon dots with dual-emission for pH sensing, Fe3+ ion detection and fluorescent ink.

In this work, a multifunctional ratiometric fluorescence (FL) nanohybrid (CSCDs@DC) was synthesized from chitosan based carbon dots (CSCDs) and dansyl chloride (DC) at room temperature. The CSCDs@DC revealed strong FL intensity, great stability and excellent anti-photobleaching properties. Herein, CSCDs@DC was responsive to pH value in the range of 1.5-4.0 and exhibited color-switchable FL properties between acidic and alkaline environments. In addition, CSCDs@DC showed good selectivity and sensitivity towards Fe3+ ions. A good linear relationship for the Fe3+ ion detection was obtained in the range from 0 µM to 100 µM, with a detection limit of 1.23 µM. What's more, CSCDs@DC can be used as a fluorescent ink. It expressed superior optical properties after 3 months of storage or continuous exposure to UV light for 24 h. This study suggested that CSCDs@DC had potential in the detection of pH and metal ions, as well as showing promising application in the anti-counterfeiting field.

DPD studies on mixed micelles self-assembled from MPEG-PDEAEMA and MPEG-PCL for controlled doxorubicin release.

In order to better understand and improve the drug loading capacity and release behavior of the pH-responsive mixed micelles in well controlled pH environments, dissipative particle dynamics (DPD) simulations are employed. This is performed by studying the co-micellization behavior of these materials produced from the two specific diblock polymers, poly(ethylene glycol) methyl ether-b-poly(N, N diethylamino ethyl methacrylate) (MPEG-PDEAEMA) and poly(ethylene glycol) methyl ether-b-polycaprolactone (MPEG-PCL) for doxorubicin (DOX) delivery. With the use of appropriate interaction parameters, the formation mechanism of (drug-loaded) mixed micelles, particle sizes, morphology, and composition are investigated. Simulation results show that compared with pure MPEG-PDEAEMA or MPEG-PCL, the mixed MPEG-PDEAEMA and MPEG-PCL system can combine to form multifunctional mixed micelles with larger particle sizes that lead to improved stability, higher drug loading capacity and better-controlled drug release performance. Simulations of the drug release process using the mixed micelles show that, when the environment is acidic, the tertiary amine group of PDEAEMA and DOX3 lead to rapid diffusion and release of the DOX in the aqueous solution. It is found that the presence of MPEG-PCL has a great influence in avoiding the fast release of the drug inside the core of micelles. Therefore, this study offers a deeper understanding of the mechanism on the co-micellization behaviors, the pH-responsive and drug controlled release behaviors of mixed micelles.

Preparation and anticoagulant properties of heparin-like electrospun membranes from carboxymethyl chitosan and bacterial cellulose sulfate.

Heparin-like membranes (CPBS) with nanofibers (approximate diameters of 100-500 nm) were prepared through electrospinning of a blended solution of carboxymethyl chitosan nanoparticle (CMCN, diameters 483 nm) and poly (vinyl alcohol) (CMCN/PVA) onto the surface of modified bacterial cellulose sulfate (BCS) membranes. SEM images confirmed that the CMCN were stretched to nanofibers during electrospinning. The presence of BCS on the collector of electrospinning machine increased the spinnability of CMCN/PVA solution. FTIR and XPS measurement revealed that there were SO3-, COO-, and OH groups on the surface of CPBS membrane, expressing structural similarity to heparin. CPBS membranes maintained hydrophilicity and the glutaraldehyde crosslinked CPBS membrane was stable in water. The clotting time and platelet adhesion experiments expressed the anticoagulant properties of CPBS. The APTT, TT and PT of CPBS increased up to 116.0%, 189.8%, and 50% than those of the plasma, (67.4 s, 16.2 s, and 48.4 s, respectively). No platelets adhered onto the surface of CPBS. An inflammatory response was determined according to activation of the macrophages seeded onto the membranes.

Fabrication of a blood compatible composite membrane from chitosan nanoparticles, ethyl cellulose and bacterial cellulose sulfate.

A heparin-like composite membrane was fabricated through electrospinning chitosan nanoparticles (CN) together with an ethylcellulose (EC) ethanol solution onto a bacterial cellulose sulfate membrane (BCS). Scanning electron microscopy images revealed that there were no chitosan particles in the obtained composite CN-EC/BCS membranes (CEB), indicating CN had been stretched to nanofibers. X-ray photoelectron spectroscopy verified the existence of -NH2 from chitosan and -SO3 - from BCS on the surface of CEB membranes. Positively charged CN in the electrospinning solution and negatively charged BCS on the collector increased the electrostatic force and the electrospinning ability of the EC was increased. The membrane was hydrophobic, with a water contact angle higher than 120°. CEB membranes expressed good blood compatibility according to the results of coagulation time and platelet adhesion experiments. No platelets adhered on the surface of the CEB membranes. An inflammatory response was investigated according to activation of the macrophages seeded onto the membranes. Macrophages seeded on CEB membranes are not activated after 24 h incubation.

Isolation, structure, and surfactant properties of polysaccharides from Ulva lactuca L. from South China Sea.

Two polysaccharides (ULP1 and ULP2) were isolated through ultrasonic-assisted extraction from green seaweed Ulva lactuca L. which was collected from the South China Sea. The highest yield of 17.57% was obtained under the conditions of 2% NaOH, 90 °C, material/water mass ratio 1:80, liquid extraction 5h and subsequent ultrasound-assisted extraction 1h. The structure of ULPs were characterized with periodate oxidation followed by Smith degradation, (1)H NMR, (13)C NMR spectroscopy, FTIR, and GPC. The molecular weights of ULP1 and ULP2 were 189 kDa and 230 kDa, respectively. The structural characteristics of ULP1 and ULP2 were quite similar. They were composed of rhamnose, xylose, glucose, and glucuronic acid. The content of rhamnose, xylose, glucose, glucuronic acid, sulfate was 51.2%, 12.3%, 20.1%, 16.4%, 12.0% for ULP1, respectively, and 60.8%, 14.2%, 8.2%, 16.8%, 26.8%, respectively, for ULP2. Both ULP1 and ULP2 showed good surface activity. 5 mg/mL ULP1 (2.62×10(-2) mmol/L) decreased the water surface tension to 51.63 mN/m. The critical micellar concentration of ULP1 and ULP2 was 1.01 mg/mL (5.3×10(-3) mmol/L) and 1.14 mg/mL (5.0×10(-3) mmol/L), respectively.

Synthesis and characterization of bacterial cellulose sulfates using a SO3/pyridine complex in DMAc/LiCl.

Various sodium bacterial cellulose sulfates (SBCS) were prepared via the homogeneous sulfation of bacterial cellulose (BC) with a SO3/pyridine (Py) complex in a dimethyl acetamide/lithium chloride solution. The SBCSs were characterized using Fourier transform infrared spectroscopy, X-ray diffraction (XRD), carbon nuclear magnetic resonance spectroscopy, gel permeation chromatography, elemental analyses, and thermal gravimetric analyses. A variety of conditions (including various amounts of SO3/Py, temperatures, and reaction times) were utilized to obtain SBCSs with DS values that ranged from 0.10 to 1.50. The XRD profiles indicated that the SBCSs had a cellulose II analog polymorphous structure. The differences between BC and microcrystalline cellulose (MC) were studied in their respective reactions. BC is more reactive than MC in both the sulfation and depolymerization processes. The order of reactivity for COH is C6>C2>C3 for both BC and MC. Cellulose sulfates with DS values >0.31 were soluble in deionized water.