Low Viscosity Carboxymethyl Cellulose Research Articles

Layered dissolving microneedle containing a three-drug combination on the treatment of hypertrophic scar

Hypertrophic scars (HS), mainly caused by burns, trauma, and surgery, are associated with erythema, bumps, itching, and pain. The oral administration of Asiaticoside (AS) is a prevalent treatment for HS in clinical settings; however, its effectiveness is constrained due to its low bioavailability, necessitating high dosages for therapeutic impact. To mitigate this issue, we developed a layered dissolving microneedle (DMN) incorporating AS–ginsenoside Rb1–L–carnosine (A–G–C) at the tip for HS treatment. The tip layer of the DMNs comprised sodium carboxymethyl cellulose (CMC), while the base layer consisted of low-viscosity CMC to enhance mechanical strength. We examined its puncture performance, in vitro dissolution ability, and therapeutic effect on a rabbit ear model of HS. Histological analysis was performed by Hematoxylin and Eosin (H&E), Masson staining and Sirius red staining. The results demonstrated that the DMNs exhibited excellent puncture performance and dissolution rates. A-G-C DMNs were found to be effective in reducing scar thickness by measuring scar thickness changes. Histological analysis revealed that the A–G–C DMNs significantly reduced inflammation and collagen fiber deposition in scar tissue. Importantly, the therapeutic effect achieved with A–G–C DMNs was comparable to that of triamcinolone acetonide injection. These findings highlight the potential of DMNs loaded with A–G–C as a promising treatment modality for HS, offering improved bioavailability and therapeutic outcomes.

Selective flotation separation mechanism of LFPs and graphite electrode materials using CMC as inhibitor

Economical and efficient separation and utilization of spent lithium iron phosphate powder is the key to lithium-ion battery recycling. Flotation, as a low-cost physical enrichment method, has attracted much attention due to its promising advantage of separating graphite before the metallurgical extraction of lithium iron phosphate. However, high-efficiency flotation separation reagent is still challenging. In this work, low-viscosity carboxymethyl cellulose (CMC) was used as a selective flotation inhibitor in the separation of graphite and lithium iron phosphate electrode materials (LFPs). With the addition of 100 mg/L 25 mPa·s CMC, the recoveries of graphite and LFPs were 96.37% and 3.47%, respectively, indicating excellent separation efficiency. The adsorption analysis and wettability measurement indicated that CMC is more favorable adsorbed on the surface of LFPs and graphite, and also greatly improved the wettability and hydrophilicity of LFPs. Meanwhile, the turbidity and particle size analysis showed that CMC could effectively disperse LFPs particles, reducing the particle entrapment caused by heterocoagulation. Furthermore, XPS and FT-IR studies confirmed that CMC could chemisorb on LFPs and physically adsorb on graphite electrode material. The study results could provide a promising physical enrichment method for the green and efficient recycling of spent lithium iron phosphate batteries.

Biochemical Characterization of an Endoglucanase GH7 from Thermophile Thermothielavioides terrestris Expressed on Aspergillus nidulans

Endoglucanases (EC 3.2.1.4) are important enzymes involved in the hydrolysis of cellulose, acting randomly in the β-1,4-glycosidic bonds present in the amorphous regions of the polysaccharide chain. These biocatalysts have been classified into 14 glycosyl hydrolase (GH) families. The GH7 family is of particular interest since it may act on a broad range of substrates, including cellulose, β-glucan, and xylan, an attractive feature for biotechnological applications, especially in the renewable energy field. In the current work, a gene from the thermophilic fungus Thermothielavioides terrestris, encoding an endoglucanase GH7 (TtCel7B), was cloned in the secretion vector pEXPYR and transformed into the high-protein-producing strain Aspergillus nidulans A773. Purified TtCel7B has a molecular weight of approximately 66 kDa, evidenced by SDS-PAGE. Circular dichroism confirmed the high β-strand content consistent with the canonical GH7 family β-jellyroll fold, also observed in the 3D homology model of TtCel7B. Biochemical characterization assays showed that TtCel7B was active over a wide range of pH values (3.5–7.0) and temperatures (45–70 °C), with the highest activity at pH 4.0 and 65 °C. TtCel7B also was stable over a wide range of pH values (3.5–9.0), maintaining more than 80% of its activity after 24 h. The KM and Vmax values in low-viscosity carboxymethylcellulose were 9.3 mg mL−1 and 2.5 × 104 U mg−1, respectively. The results obtained in this work provide a basis for the development of applications of recombinant TtCel7B in the renewable energy field.

Feeding juvenile largemouth bass (Micropterus salmoides) with carboxymethyl cellulose with different viscous: Impacts on nutrient digestibility, growth, and hepatic and gut morphology

A 56-day trial investigated the impact of the dietary inclusion of cellulose with different viscosities on the growth, nutrient digestibility, serum biochemical indices, and the hepatic and gut morphology of largemouth bass juveniles. Four practical diets (42.50% protein and 13.70% lipid) were designed containing 8% microcrystalline cellulose (MC) and carboxymethyl cellulose (CMC) of 2,500, 5,000, and 6,500 mPa s dynamic viscosity [named MC, low-viscosity CMC (Lvs-CMC), medium-viscosity CMC (Mvs-CMC), and high-viscosity CMC (Hvs-CMC) groups, respectively]. Fish of a uniform size (6.0 g) were randomly assigned into 16 cages, with 40 fish per cage. The results showed that the protein and lipid deposition rates, specific growth rate, protein efficiency ratio, and the weight gain rate decreased significantly in the CMC groups compared to the MC group, whereas the feed intake and feed coefficient rate exhibited the opposite trend. Moreover, the intestinal Na+/K+-ATPase, alkaline phosphatase, and lipase activities significantly decreased in the Mvs-CMC and Hvs-CMC groups compared to the MC group, as well as the serum triglyceride, total cholesterol, and high-/low-density lipoprotein contents. The nutrient apparent digestibility significantly decreased in the CMC groups compared to the MC group. The viscerosomatic and intestinal length indices in the CMC groups and the villus height in the Hvs-CMC group were significantly lower than those in the MC group, whereas the number of gut goblet cells and muscular thickness in the Mvs-CMC and Hvs-CMC groups exhibited opposing results. The results also showed that dietary CMC damaged the hepatic and gut morphology and decreased the digestive enzyme activity, nutrient apparent digestibility, and growth of largemouth bass. In summary, viscosity is the main anti-nutritional effect of dietary CMC and soluble non-starch polysaccharides.

Rheological Behavior and Filtration of Water-Based Drilling Fluids Containing Graphene Oxide: Experimental Measurement, Mechanistic Understanding, and Modeling.

Any improvement in drilling technology is critical for developing the oil and gas industry. The success of drilling operations largely depends on drilling fluid characteristics. Drilling fluids require enough viscosity to suspend the particles and transport them to the surface and enough capability to control the fluid loss into the formation. Rheology and filtration characteristics of drilling fluids are crucial factors to consider while ensuring the effectiveness of a drilling operation. Graphene oxide (GO), xanthan gum (XG), and low-viscosity carboxymethyl cellulose (CMC LV) are being utilized in this research to produce high-performance, low-solid water-based drilling fluids (WDFs). Rheological and filtration behaviors of GO/XG/CMC LV-WDF were investigated as a function of GO, XG, and CMC LV at low concentrations (0.0–0.3% w/w) and atmospheric conditions. According to the findings, GO improved the rheological and filtration capabilities of the WDF. By adding 0.15 wt % GO, shear stress could be doubled, especially at a high shear rate of 1022 s–1. The plastic viscosity of the fluid could be expanded from 6 to 13 centipoise, and a fluid loss of 8.7 mL over 30 min was observed during the API fluid test, which would be lower than the suggested fluid loss value (15.0 mL) for water-based mud. At the same concentration of XG and CMC LV, XG had a more significant influence on rheological characteristics in the presence of GO. Adding 0.3 wt % XG could increase fluid shear stress from 20.21 to 30.21 Pa at a high shear rate of 1022 s–1. In contrast, CMC LV had more impact on filtration properties, acting as a filtration control agent by decreasing the API fluid loss of fluid from 21.4 to 14.2 mL over 30 min. The addition of XG and CMC LV to the GO solution may influence the microstructure of the filter cake, resulting in a tree-root morphology. Indeed, in the GO/CMC LV solution, the individual platelets may bind together, form a jellyfish shape, and block the micropores. The incorporation of CMC LV helped develop compact filter cakes, resulting in excellent filtration. Five rheological models were employed to match the fluid parameters quantitatively. The Herschel–Bulkley model outperformed the other models in simulating fluid rheological behavior. The findings of this study can be utilize to provide low-cost, stable, and environmentally compatible additives for drilling low-pressure, depleted, and fractured oil and gas reservoirs.

Centella asiatica Extract Potentiates Anticancer Activity in an Improved 3-D PHBV-Composite-CMC A549 Lung Cancer Microenvironment Scaffold

Traditional cell culture makes use of two-dimensional (2-D) surfaces for unnatural characteristics in vitro cell response and growth. To overcome the limitation, 3-D culture models mimicking the cancer microenvironment in vivo are gaining attention. Herein, we investigated an improved composite 3-D biomimetic structure comprising poly(hydroxybutyrate-co-hydroxyvalerate) and carboxymethylcellulose (CMC) (PHBV-co-CMC) for determining the potentiation effects of Centella asiatica extract on lung cancer cells (A549). To improve its biological acceptance characteristics, the 3-D scaffold was infused with low viscosity CMC gel (0.009 ± 0.0004 Pa s) under vacuum pressure. The composite material was left immersed in complete growth media with the presence of cells to determine its optimum day of degradation prior to anti-proliferative (IC50) analysis through 2-D and 3-D cell culture. All scaffolds were found to be sustained for up to 7 days of incubation with breakages ranging from 10 to 70% (w/w). The A549 cell mortality treated with the extract (IC50 5.75 ± 1.0 µg/ml) on both porous 3-D PHBV and composite-CMC scaffolds were 70% higher than the 2-D model (30%) (p < 0.05). Visual assessment on the inner structure of the 3-D scaffold using fluorescent microscopy and scanning electron microscopy showed a scattering number of living cells on the scaffold pores wall and on the CMC gel with a glowing blue color indicating the presence of a livable cells post DAPI dye staining. Therefore, the structure of composite 3-D PHBV scaffold co-CMC produced a potential alternative method of a 3-D cell culture model to study the effectiveness of medicinal plant extracts (e.g. anticancer properties) in which might potentially mimic specific cancerous tissue ex vivo.

Study on Wellbore Temperature and Pressure Distribution in Process of Gas Hydrate Mined by Polymer Additive CO2 Jet

In order to solve the problem of hydrate reservoir collapse and hydrate regenerated in the process of solid fluidization of natural gas hydrate, a new method of natural gas hydrate exploit by high‐polymer additive (low viscosity carboxymethyl cellulose LV‐CMC) carbon dioxide jet was proposed. The wellbore temperature and pressure changes during this process are analyzed, and the wellbore temperature and pressure model are established and solved by the state space method. This paper also analyzed the effects of relevant parameters on hydrate decomposition, such as injection flow, temperature, and pressure. The results show that increasing the injection pressure allows the hydrate decomposition site to be closer to the annulus outlet. Compared with water, with polymer additive CO2 fluid as the drilling fluid, the intersection point of phase equilibrium curve and annular pressure curve is closer to annular outlet, which is obviously more conducive to well control. In order to avoid phase changes, the injection pressure of the carbon dioxide fluid of the high‐polymer additive should not be lower than 10 MPa, and the injection temperature should not be higher than 285 K.

Polysaccharide food matrices for controlling the release, retention and perception of flavours

Polysaccharides have many roles across both the food and pharmaceutics industries. They are commonly used to enhance viscosity, stabilise emulsions and to add bulk to food products. In the pharmaceutics industry, they are also utilised for their mucoadhesive nature. Mucoadhesive polysaccharides can facilitate retention of active ingredients at mucosal sites for a prolonged time and formulations can be designed to control their release and bioavailability. This study investigates how polysaccharides, with differing physicochemical properties (e.g. functional groups and molecular weight), affect the release and perception of flavour compounds from films. Polysaccharide films were prepared using either high or low viscosity carboxymethyl cellulose, pullulan or hydroxypropyl methylcellulose. Glucose, vanillin or a combination of both was also added to the films to assess the effect of flavour release and perception over time. The films were assessed for glucose release in vitro, swelling and disintegration times, and mucoadhesive ability. Results show that flavour release and perception depend on the polysaccharide matrix properties; this includes how quickly the films dissolve, the rate of release of tastant compounds, and the mucoadhesive strength of the polysaccharide. A higher viscosity and slower disintegration time resulted in slower release of glucose in vitro and flavour perception in vivo.

Influence of Clay Swelling Inhibitor in Filtration Properties of Water-Based Drilling Fluids

This work aims to evaluate the influence of the clay swelling inhibitor in the filtration properties of water-based drilling fluids. Drilling fluids were prepared with and without adding potassium citrate clay inhibitor. The following additives were used in the composition of the fluid: viscosity agent (xanthan gum), filtrate reducer (starch and low viscosity carboxymethylcellulose (CMC LV)), antifoam, bactericide, sealant (calcite), lubricant and pH controller. The concentration of inhibitor was used of 15, 20, 25 and 30 g/ 350 mL of water. We determined the filtration properties (filtrate volume (FV), spurt loss (SL), cake thickness (CT) and permeability (K)) of drilling fluids. According to the results, it was concluded that: (i) adding the inhibitor to the fluid promoted reduction of FV and K of fluids containing starch in the composition and (ii) the inhibitor promoted satisfactory reductions in the CT and increased of SL for all the studied fluids. Finally, the inhibited fluids prepared with higher concentrations of starch, CMC LV, calcite and potassium citrate than 25 g/ 350 mL of water showed the best performance compared to FV and SL.

Advanced biomaterial strategies to transplant preformed micro-tissue engineered neural networks into the brain

Objective. Connectome disruption is a hallmark of many neurological diseases and trauma with no current strategies to restore lost long-distance axonal pathways in the brain. We are creating transplantable micro-tissue engineered neural networks (micro-TENNs), which are preformed constructs consisting of embedded neurons and long axonal tracts to integrate with the nervous system to physically reconstitute lost axonal pathways. Approach. We advanced micro-tissue engineering techniques to generate micro-TENNs consisting of discrete populations of mature primary cerebral cortical neurons spanned by long axonal fascicles encased in miniature hydrogel micro-columns. Further, we improved the biomaterial encasement scheme by adding a thin layer of low viscosity carboxymethylcellulose (CMC) to enable needle-less insertion and rapid softening for mechanical similarity with brain tissue. Main results. The engineered architecture of cortical micro-TENNs facilitated robust neuronal viability and axonal cytoarchitecture to at least 22 days in vitro. Micro-TENNs displayed discrete neuronal populations spanned by long axonal fasciculation throughout the core, thus mimicking the general systems-level anatomy of gray matter—white matter in the brain. Additionally, micro-columns with thin CMC-coating upon mild dehydration were able to withstand a force of 893 ± 457 mN before buckling, whereas a solid agarose cylinder of similar dimensions was predicted to withstand less than 150 μN of force. This thin CMC coating increased the stiffness by three orders of magnitude, enabling needle-less insertion into brain while significantly reducing the footprint of previous needle-based delivery methods to minimize insertion trauma. Significance. Our novel micro-TENNs are the first strategy designed for minimally invasive implantation to facilitate nervous system repair by simultaneously providing neuronal replacement and physical reconstruction of long-distance axon pathways in the brain. The micro-TENN approach may offer the ability to treat several disorders that disrupt the connectome, including Parkinson’s disease, traumatic brain injury, stroke, and brain tumor excision.

Abstracts fromThe 32nd AnnualNational Neurotrauma SymposiumJune 29–July 2, 2014San Francisco, California

Abstracts fromThe 32^nd AnnualNational Neurotrauma SymposiumJune 29–July 2, 2014San Francisco, California

The Modification of Rheological Properties of Sodium Bentonite-water Dispersions with Low Viscosity CMC Polymer Effect

Due to their exceptional rheological properties, bentonites are used in different branches of industry, such as in drilling fluids, dyes, pharmaceuticals, paper, cement, nanocomposites, polymer composites, and ceramics. In the use of bentonite in different applications, the addition of carboxymethyl cellulose (CMC) sodium salt is recommended to optimize the rheological properties of the suspension. In this study, the effect of carboxymethyl cellulose on the rheological properties of Na-bentonite suspensions was investigated in the polymer concentration range of 0.02–0.50 wt%. The addition of carboxymethyl cellulose to the bentonite dispersions resulted in significant increase in the dispersion viscosity. The advantage of carboxymethyl cellulose is that the desired rheological properties can be obtained with less bentonite by adding carboxymethyl cellulose polymer and the undesirable effects of high bentonite concentrations can be avoided. The viscosity of 8.0 wt% pure bentonite dispersions was achieved by adding 0.10 wt% carboxymethyl cellulose to 4.0 wt% bentonite dispersions. The combined flow behaviors of Bingham and shear thickening observed for the 4.0 wt% pure bentonite dispersion was shifted toward the shear thinning profile with a yield stress in the presence of the carboxymethyl cellulose. This yield stress increased substantially with carboxymethyl cellulose concentration. In addition, the thixotropic behavior of bentonite dispersions was significantly enhanced by adding carboxymethyl cellulose polymer.

Precorneal Residence Time of Artificial Tears Measured in Dry Eye Subjects

The purpose of this investigation was to measure the precorneal residence time of saline and five marketed artificial tears in dry eye subjects using fluorometry. FITC-dextran, 70 kDa molecular weight, was admixed under sterile conditions (0.1% wt/vol) into buffered saline and the marketed artificial tear formulations of varying viscosity. Precorneal residence time (RT) was measured directly in 16 mild to moderate dry eye subjects, classified by sub-type, in a six-way cross-over, masked and randomized study. FITC-dextran tracer decay with a scanning fluorometer was used to estimate the gross RT (i.e., the time in minutes for the signal to return to baseline). All subjects were classified as having non-inflammatory meibomian gland dysfunction except one, who had a mixture of aqueous deficiency and meibomian gland dysfunction. In two separate determinations, the saline RTs were 19.1 +/- 7.4 and 17.6 +/- 8.2 min. The RTs for the formulations varied to some degree by viscosity, with two higher viscosity formulations demonstrating the longest RTs of 36 to 41 min, approximately twice that of saline (p < 0.001 for both 0.4% polyethylene glycol/0.3% propylene glycol, and 1.0% carboxymethylcellulose). An oil emulsion, low viscosity carboxymethylcellulose and moderate viscosity hydroxypropylmethylcellulose-containing formulation were not statistically different from saline (RTs of 18, 22 and 24 min, p values = 0.983, 0.818 and 0.099, respectively). More than two-fold RT differences were found for the higher viscosity, more muco-adhesive formulations compared to saline. However, other formulations provided RTs close to saline, suggesting that RT is influenced by factors other than simple viscosity. Future studies should examine the interplay of spreading characteristics, pseudoplasticity and muco-adhesion relative to RT to determine the individual and cumulative effects on formulation retention.

Influence of ionic strength on the viscosities and water loss of bentonite suspensions containing polymers

A study was made of the influence of ionic strength (S) on the apparent (AV) and plastic (PV) viscosities and water loss (WL) of sodium bentonite suspension with polymers. Na-bentonite was dispersed in water (4.86% w/w) of different ionic strengths (S = 0.0, 0.015, 0.030 and 0.045 M) followed by the addition of polymer. Three polymer samples were studied, i.e., low viscosity carboxymethyl cellulose (CMC BV), polyanionic cellulose (PAC), and partially hydrolyzed polyacrylamide (HPAM). The results indicated that the presence of salts and increased salinity greatly influence the apparent and plastic viscosities and water loss of bentonite suspensions with polymer.

Phosphate removal by refined aspen wood fiber treated with carboxymethyl cellulose and ferrous chloride

Biomass-based filtration media are of interest as an economical means to remove pollutants and nutrients found in stormwater runoff. Refined aspen wood fiber samples treated with iron salt solutions demonstrated limited capacities to remove (ortho)phosphate from test solutions. To provide additional sites for iron complex formation, and thereby impart a greater capacity for phosphate removal, a fiber pretreatment with an aqueous solution of a non-toxic anionic polymer, carboxymethyl cellulose (CMC), was evaluated. Problems with excessive viscosities during the screening of commercially available CMC products led to the selection of an ultra low viscosity CMC product that was still usable at a 4% concentration in water. Soxhlet extractions of chipped aspen wood and refined aspen wood fiber samples showed a higher extractives content for the refined material. Analysis of these extracts by FTIR spectroscopy suggested that the higher extractives content for the refined material resulted from the fragmentation of cell wall polymers (e.g., lignin, hemicelluloses) normally insoluble in their native states. Spectroscopic analysis of CMC and ferrous chloride treated fibers showed that the complex formed was sufficiently stable to resist removal during subsequent water washes. Equilibrium sorption data, which fit better with a Freundlich isotherm model than a Langmuir isotherm model, showed that phosphate removal could be enhanced by the CMC pretreatment. Results suggest that the process outlined may provide a facile means to improve the phosphate removal capacity of biomass-based stormwater filtration media.

Liver nitrogen movements during short-term infusion of high levels of ammonia into the mesenteric vein of sheep.

Four 40 kg wethers were used in a crossover design to quantify, by arterio-venous procedures, the mass transfer of NH3, urea and amino acids (AAs) across the portal-drained viscera and the liver during a 31 min infusion of either 0 (C0) or 1100 (C1100) micromol NH4HCO3/min into the mesenteric vein. In C1100, hepatic NH3 extraction remained stable at 1214 micromol/min (1.90 micromol/min per g wet liver weight), the capacity for hepatic NH3 removal was exceeded by 654 micromol/min and the incremental (C1100-C0) urea-N release: NH3 -N removal ratio increased progressively, from 0.52 to 0.90. The NH4HCO3 infusion reduced total branched-chain AA transfer across the portal-drained viscera and total AA-N and lysine extraction by the liver. Hepatic release of glutamate was augmented ornithine switched from net release to net removal and net splanchnic release of free essential AA (44 micromol/min (sed 9.2), ) and branched-chain AA (33 micromol/min (sed 2.0), ) were reduced to 0.58 of their basal rate. The study showed that conversion of excess NH3 to urea during a short-term hepatic NH3 overload required no additional contribution of AA-N to ureagenesis; essential AA and branched-chain AA supply to non-splanchnic tissues was, however, temporarily decreased.

Increasing viscosity of the intestinal contents alters small intestinal structure and intestinal growth, and stimulates proliferation of enterotoxigenicEscherichia coliin newly-weaned pigs

Sources of viscous soluble fibre, such as barley and oats, have often been included in the weaning diet of the pig to accelerate development of the large intestine. Inclusion of a non-fermentable, viscous compound, sodium carboxymethylcellulose (CMC), in a low-fibre weaning diet was tested to assess the influence of digesta viscosity on the gut in the absence of increased fermentation. Two CMC sources, of low and high viscosity, were added to cooked rice-based diet at 40 g/kg total diet. A third control rice diet did not contain any CMC. Diets were fed for 13 d following weaning at 3 weeks of age. Addition of CMC to the diet significantly increased the intestinal viscosity of digesta within the small (P<0.001) and large (P<0.05) intestine. No simple association was found between increases in intestinal viscosity and effects on intestinal morphology and whole-body growth. The average empty-body-weight gain and the small intestinal villus height increased with low-viscosity CMC, but decreased with the high-viscosity CMC group. The full large intestinal weight increased in all pigs fed CMC. Dietary CMC (both low- and high-viscosity) increased the percentage moisture of digesta and faeces, and was associated with increased faecal shedding of enterotoxigenic haemolytic Escherichia coli. Feed ingredients in weaning diets that excessively increase the viscosity of the intestinal digesta may be detrimental to pig health and production.

Reduction of oil uptake in deep fried tortilla chips Reducción de la absorción de aceite en la fritura de tiras de maíz

The reduction of oil uptake in fried tortilla chips was attempted with baking and carboxymethyl cellulose (CMC) addition. The effects of CMC type and concentration, frying time, and prefrying treatment on oil uptake and moisture content were studied. Chips were prepared using corn masa flour. Results showed that the addition of CMC reduced the oil uptake significantly for all samples. The reduction in oil uptake ranged from 5-40% according to the CMC type and concentration. The most effective CMC type was high viscosity, which caused a 40% reduction in oil content for 30 s frying time of baked samples. The addition of CMC also reduced the initial moisture content of raw chips. The highest moisture content reduction was for samples prepared with low-viscosity CMC. Frying time was an important factor on oil uptake and moisture content. When frying time increased, oil content increased while moisture content decreased.

Agglomeration Tendency during Top-Spray Fluidized Bed Coating with Gums

Top-spray fluidized bed coating of glass beads with gums leads to an `all or nothing' side-effect agglomeration in the case of locust bean gum, carboxymethylcellulose (CMC), and sodium alginate, meaning that it appeared very drastically when a critical spray rate was exceeded. By contrast, a continuous sticking of the particles onto the reactor wall was observed for κ-carrageenan. It was illustrated that wet film properties instead of solution properties determine agglomeration tendency since locust bean gum, high and low viscosity CMC show a comparable agglomeration tendency. The glass transition concept offers some relevant explanation as to why κ-carrageenan permits working at considerably higher spray rates than sodium alginate, although both biopolymers show similar hygroscopical and rheological characteristics. Glass transition phenomena also seem to influence the magnitude of coating imperfections: coatings consisting of locust bean gum and κ-carrageenan appear to have a surprisingly uniform structure.

Intranasal Administration of HIV-DNA Vaccine Formulated with a Polymer, Carboxymethylcellulose, Augments Mucosal Antibody Production and Cell-Mediated Immune Response

We previously reported that intramuscular (i.m.) immunization of DNA vaccine encoding human immunodeficiency virus type 1 (HIV-1)IIIBenvandrevgenes alone or in combination with appropriate adjuvant induces substantial and enhanced immune response against HIV-1. In the present study, we examined whether a polymer, low-viscosity carboxymethylcellulose sodium salt (CMCS-L), has an adjuvant effect on immune response induced by DNA vaccination. BALB/c mice were immunized with HIV-DNA vaccine formulated with CMCS-L via the intranasal (i.n.) and i.m. routes. The combination with the polymer elicited higher levels of antigen-specific serum IgG and fecal IgA antibodies than DNA vaccine alone. For cell-mediated immunity, HIV-specific delayed-type hypersensitivity response and cytotoxic T lymphocyte activity were measured by the footpad-swelling test and the51Cr-release assay, respectively. Both were enhanced by the combination with CMCS-L via i.n. and i.m. inoculation. Cytokine analysis in culture media of bulk splenocytes harvested from immunized animals showed higher levels of IL-4 production in i.n.-immunized mice compared with i.m.-immunized mice. Nevertheless, the increased IFN-γ production resulting from the combination with CMCS-L was observed only in i.n.-immunized mice. These data indicate that i.n. immunization of HIV-DNA vaccine formulated with CMCS-L enhances HIV-specific mucosal antibody (Ab) and systemic Ab and cell-mediated immune response.