Sodium Carboxymethyl Starch Research Articles

A Comparison of Some Methods for the Determination of the Degree of Substitution of Carboxymethyl Starch

The degree of substitution (DS) markedly affects the properties of sodium carboxymethyl starch (Na-CMS). In this work Na-CMS samples with different DS starting from both potato and corn starch were synthesized in an ethanol/water mixture and their DS was determined using three methods: direct titration of the acid form of the carboxymethyl starch (H-CMS), Cu salt precipitation and back titration. It was found that direct titration gave smaller DS values, while the Cu salt precipitation method gave higher DS values than the back titration method, which was found to be the most accurate. The values of the DS obtained by these methods were similar for lower DS while for higher values the discrepancy was more pronounced. Under the same experimental conditions the CMS obtained from corn starch had a higher DS than the one obtained from potato starch and on average, the discrepancies between the DS values obtained by the employed analytical methods were smaller for the CMS samples synthesized from corn starch.

Development of an enteric-coated pellet formulation of F4 fimbriae for oral vaccination of suckling piglets against enterotoxigenic Escherichia coli infections

A multi-particulate formulation of F4 fimbriae was developed for oral vaccination of suckling piglets against enterotoxigenic Escherichia coli infections. A feasibility test showed that incorporation of F4 fimbriae in a disintegrating pellet formulation consisting of 87.5% Pharmatose ® 200 M, 2.5% Avicel ® CL 611 and 10% Explotab ® by extrusion/spheronisation and subsequent fluid bed drying resulted in the maintenance of 69±12% of the biological activity. But subsequent coating resulted in pellets with poor enteric properties, although good in vivo immunising results were obtained after administration to piglets. From the economical point of view, a pellet formulation was optimised to decrease vaccine dose and dosing frequency. After disintegration testing, pellets consisting of lactose (α-lactose monohydrate 90 mesh/β-lactose 75/25 (w/w)) and microcrystalline cellulose in a ratio of 80/20 (w/w) showed a sponge-like structure from which F4 fimbriae could be released. Coating of these pellets resulted in good enteric properties. To improve disintegrating properties of the pellets, the lactose concentration was increased or sodium carboxymethyl starch was added. But this resulted in poor enteric properties after coating. Dissolution test showed that F4 fimbriae were released from the optimised enteric-coated pellets but interaction between F4 fimbriae and the coating polymer was seen. This incompatibility leads to unpredictable in vitro quantification of F4 biological activity.

Mucoadhesive alginate matrices containing sodium carboxymethyl starch for buccal delivery: in vitro and in vivo studies

The aim of this paper was to investigate the development of buccal mucoadhesive tablets (hydrophilic matrices) intended for the local delivery of an antimicrobial drug, chlorhexidine diacetate, in the oral cavity over a prolonged period of time. Sodium alginate was selected as the mucoadhesive polymer. Sodium carboxymethyl starch was used in different weight ratios to modulate the matrix erosion/drug release. The antimicrobial activity of the drug/excipient mixtures was investigated for the minimum inhibitory concentration and minimum candidicidal concentration. Buccal tablets were prepared by direct compression and studied by in vitro drug release and in vitro mucoadhesion tests. The tablets were characterised by a prolonged in vitro drug release. Sodium alginate exhibited good mucoadhesion behaviour. After their in vivo administration, the determination of chlorhexidine in saliva showed that the formulations characterised by the presence of the highest percentage of sodium carboxymethyl starch had the capacity to give a prolonged release of chlorhexidine in the buccal cavity. This behaviour was related to the in vivo erosion of the matrices. These preliminary results indicate that these matrices can be proposed as buccal mucoadhesive systems for the intraoral prolonged delivery of drugs.

Development and in vitro evaluation of an enteric-coated multiparticulate drug delivery system for the administration of piroxicam to dogs

The aim of the study was to develop enteric-coated pellets for the administration of piroxicam (a poorly water-soluble drug) to small animals in order to avoid local gastrointestinal irritation, one of the major side effects of nonsteroidal anti-inflammatory drugs after oral ingestion. Pellets were made by an extrusion–spheronization process. The influence of several excipients on the in vitro drug release was evaluated. Piroxicam release from the uncoated pellets was measured in phosphate buffer (pH 6.8) using the paddle dissolution method (USP XXIII). The enteric-coated pellets were tested in 0.1 N HCl and phosphate buffer, pH 6.8. The addition of sodium croscarmellose (Ac-Di-Sol) did not influence the piroxicam release from microcrystalline cellulose pellets. Sodium carboxymethyl starch (Explotab) increased the release from 30 to 65% at 45 min. The incorporation of sodium carboxymethyl cellulose on its own or as a co-processed blend with microcrystalline cellulose (Avicel RC 581 and CL 611) enhanced the release of piroxicam at 45 min from 30% (pure Avicel PH 101) to 95% (combination of Avicel PH 101 and CL 611 in a ratio of 1:3). Additional use of cyclodextrins had only a minor influence on the dissolution rate. An Eudragit L 30 D-55 and FS 30 D (6/4) film was applied to the core pellets (containing 2.5% (w/w) piroxicam and a combination of Avicel PH 101 and CL 611 in a ratio of 1:3) in order to obtain gastroresistant properties. The coated pellets retained their dissolution characteristics after compression into fast disintegrating tablets because waxy cushioning beads were added to minimize film damage.

Fast- and Slow-Release Tablets for Oral Administration of Flavonoids: Rutin and Quercetin

ABSTRACTMany derivatives of rutin (Rt) and its metabolite quercetin (Q) are employed in clinics for cardiovascular chronic pathology, and are also known for their antiulcer behavior in vivo and antiproliferative and antimutagenic activity in vitro. Unfortunately, the absorption of quercetin and rutin from the gastrointestinal tract is slow and irregular, probably due to their very slight solubility in water and slow dissolution rate.In this work the dissolution rate of the drugs from oral formulations has been improved using some enhancers such as cross-linked sodium carboxymethylcellulose (CMC-XL), sodium carboxymethylstarch (E), and cross-linked polyvinylpyrrolidone (P). The drugs were loaded on the hydrophilic carriers by different techniques such as mixing or co-milling. The in vitro dissolution profiles of the mixed or co-milled drug/polymer systems, obtained in various media with different pH, were compared. The results show that the drug dissolution rate from the co-milled drug/carrier systems is faster than that from mixed systems, and CMC-XL and sodium carboxymethylstarch systems are able to enhance the dissolution rate. For this reason, these co-milled drug/carrier systems were used for the production of both fast- and slow-release tablets. The co-milled drug/CMC-XL system was used for the preparation of fast-release tablets containing rutin, while three different fast-release tablets were formulated and tested using respectively Q/CMC-XL, Q/E, and Q/P co-milled systems.The effect of the presence of sodium lauryl sulfate in the aqueous medium on the dissolution profile of flavonoids alone was also studied.The prolonged-release formulations have been developed using hydroxypropylmethylcellulose (HPMC) of different viscosity grades as retarding polymer. An extended release of the drugs for times ranging from 6 to 14 hr could be obtained, depending on the type and viscosity of the HPMC used.

The solution stability of vancomycin in the presence and absence of sodium carboxymethyl starch

The purpose of this work was to study the potential for drug-excipient interactions to alter the stability of pharmaceutical drug products. Previous studies have demonstrated the interactions between glycopeptide antibiotics (e.g. vancomycin) and sodium carboxymethyl starch (NaCMS). A key objective of this work was to determine the effect of NaCMS binding on the solution stability of the glycopeptide antibiotic, vancomycin. The solution stability of vancomycin was studied under various pH and ionic strength conditions at physiological temperature (37°C). A stability-indicating HPLC method specific for vancomycin was developed and validated for use in this research. Vancomycin stability was evaluated alone and in the presence of NaCMS in various buffers from pH 2 to 9, and in simulated gastric and intestinal fluids to determine if NaCMS influences the degradation rate of vancomycin in solution. Results indicated that the pH stability profile of vancomycin at 37°C from pH 2 to 7 was slightly stabilized in the presence of NaCMS at the pH and ionic strength conditions where binding to NaCMS was shown to occur.

Thermal Decomposition of Sodium Carboxymethyl Starch.

Potato starch (PS) was carboxymethylated with monochloroacetic acid to prepare sodium carboxymethyl starches (Na-CMSs) with different degrees of substitution (DS) at the OH moieties, and their first thermal decomposition was invesitigated at 200 to 300°C. Chemical analyses suggested that Na-CMSs (1), (2) and (3) having DS≤0.3 were the compounds substituted with carboxymethyl groups at the primary OH moieties and Na-CMSs (4), (5) and (6) having 0.3≤DS<1.1 at both primary and secondary OH moieties. Remarkable differences in weight decrease curves and onset temperatures of thermal decomposition were observed between the two groups, Na-CMSs (1)-(3) and Na-CMSs (4)-(6). Upon heating, the C=O bonds based on carboxymethyl groups of Na-CMSs (1)-(3) were partially decomposed, although their structures were unclear. In contrast, the decomposition of C-O bonds based on intra- and inter- molecular ether linkages or hydroxyl groups in the glucose units was mainly observed for Na-CMSs (4)-(6). The increase of DS accompanied the increase of activation energy, but there was no significant difference in the activation energy among Na-CMSs (4), (5) and (6).

A Practical Procedure for the Cryopreservation of Marrow Cells Intended for Autotransplantation

A simple and practical method of unfractionated bone marrow processing and cryopreservation was studied. The date shows that RBCs can be rapidly sedimented by methylcellulose or sodium carboxymethyl starch within 15-45 min. The cells can be cryopreserved in a mixture consisting of 5% DMSO, 6% HES and 4% Albumin prepared in a Lactated Ringer solution which is widely used, and can be simply immersed into a -80 degrees C freezer and stored in liquid nitrogen until infusion. Recovery percentages of nucleated cell, cell viability and CFU-G were similar to those cryopreserved with the conventional method. Clinical toxicity was mild in 12 infused patients. Of them 8 patients had received high dose chemotherapy +/- TBI and their peripheral WBC recovery was rapid. The recovery of WBC or Platelet (PLT) in the study group was similar to that of the control group whose marrow cells were cryopreserved in 10% DMSO. Therefore, cells cryopreserved with this method can also accelerate the hematopoietic recovery in myeloablatively treated patients.

Micropores in Sodium Carboxymethyl Starch and Their Role in Moisture Sorption

Micropores in Sodium Carboxymethyl Starch and Their Role in Moisture Sorption

Tablettenreste im magen-darminhalt? Eine polarisationsmikroskopische suchmethode zur raschen Aussage am Sektionstisch

When tablet residues are found in the gastrointestinal tract during autopsy, this does not only indicate the possible presence of intoxication, but may also provide indications with the regard to the kind of intoxication (e.g. suicide) if the amount of tablets is considered. If tablets have already dissolved and thus large portions can no longer be detected with the naked eye, a definitive appraisal with regard to the presence of tablet residues is often difficult or even impossible on the autopsy table. A polarization microscopic screening method is described which enables identification of characteristic tablet auxiliary substances (maize starch, sodium carboxymethyl starch, microcristalline cellulose or sodium carboxymethyl cellulose) to be identified immediately and simply in the gastrointestinal contents. It also enables a rapid orientative screening for tablet residues in glasses found or the fluid these contained as well as in aspirated material and vomit. If the active agent of the tablet can be detected by chemical toxicology, the polarization microscopic diagnosis of abundant tablet auxiliary substances is compatible with intake of large amounts of drugs, which makes self-administration highly probable.

Using carboxymethylated cassava ( Manihot) wastes as thickeners for latex paint

Cassava ( Manihot) starch wastes carboxymethylated to a degree of substitution in the range of 0·42–0·61 have been prepared and used as thickening agents for the formulation of water-based latex paints. It was found that paint thickened with cassava-waste-based sodium carboxymethyl starch acquires a mechanical strength and drying time comparable to paint formulated with the commercial grade thickeners such as Tylose and Natrosol.

The Release of Disperse Dyes from Thickener Films during Thermal Processes

The dye release properties of hydrophilic polymer layers containing disperse dye particles have been studied.Polymers which form homogeneous films, such as sodium alginate, act as barriers to the passage of dye vapour, unless the weight of the dye particles initially present in the layer exceeds the weight of polymer. Sodium carboxymethyl starch does not behave in this way, as the polymer film is heterogeneous.Evidence is presented for much improved dye release from coatings containing homogeneous film–forming polymers by the emulsification of hydrocarbons into print pastes. The driedcoatings take on a cellular structure which allows disperse dye vapour to be readily released.

In Vitro Release of Hydrochlorothiazide from Capsule Formulations

AbstractFive different hydrochlorothiazide (50mg. per capsule) capsule formulations were prepared with one of the following diluents: corn starch, dibasic calcium phosphate, lactose, microcrystalllne cellulose, or sodium carboxymethyl starch. A comparative dissolution study was conducted using the USP procedure. Significant differences (p = 0.05) were found among the formulations relative to in vitro dissolution rates over a two-hour sampling period. The formulations prepared with lactose consistently ranked near the top (Newman-Keuls multiple range test) while the formulation prepared with sodium carboxymethyl starch ranked last at each sampling time except 3 min.

Studies on Biochemical Hydrolysis of Sodium Carboxymethylstarch (V)

Studies on Biochemical Hydrolysis of Sodium Carboxymethylstarch (V)

Studies on Biochemical Hydrolysis of Sodium Carboxymethylstarch (IV)

Studies on Biochemical Hydrolysis of Sodium Carboxymethylstarch (IV)

Studies on Biochemical Hydrolysis of Sodium Carboxymethylstarch (II)

Sodium carboxymethylstarch (Na-CMS) labeled on the position of 2-C carboxymethyl group was prepared, and its 2% aqueous solution was administered to the rat by gastric intubation, and the resultant radioactivity of the solution was estimated at 0.8Ci/ml.The author found that 5.6% of the radioactivity was expired as CO2 within 96 hours, 1.8% excreted into the urine and 83% found in the faeces.The urine was tested by thin layer chromatography using cellulose powder as adsorbent. As the result, three bands were conspicuous to some extent than the others. The first band, which was regarded as Na-CMS contaminated with faeces, was found on the starting line, the second band at the point of the Rf value 0.37 regarded as glucose derivative, and the third band at the point of the Rf 0.67 whose entity was not known.Na-CMS in the faeces was determined with 2, 7-dihydroxynaphthalene, which was 79.1% of the dosage administered.

Studied on Biochemical Hydrolysis of Sodium Carboxymethylstarch (III)

Low molecular substances produced by the hydrolysis of sodium carboxymethylstarch (Na-CMS, degree of substitution: 0.38) with saliva amylase were studied.Na-CMS was hydrolyzed with human saliva amylase, and the hydrolyzates were fractionated by Sephadex column to No. 1-5 portions. The fraction 1 showed a different behavior from the other fractions on paper chromatogram, and it was colored to violet (absorption maximum: 540mμ) by heating with 0.01% 2, 7-dihydroxy-naphthalene sulfuric acid solution in water bath. Infrared spectrum of the fraction showed the absorption of carboxyl group. These facts revealed the presence of a carboxymethyl group in the fraction 1, but in the fraction 2-5, respectively carboxymethyl group was not identified. The fraction 1 was not colored with iodine, and the average polymerization degree of the fraction 1 was 7.5 by the determination with 3, 5-dinitrosalicylic acid method.

Studies on Biochemical Hydrolysis of Sodium Carboxymethylstarch (I)

Hydrolysis of sodium carboxymethylstarch (Na-CMS) with human saliva was studied. Na-CMS with high degree of substitution (H.D.S. -CMS) and Na-CMS with low degree of substitution (L.D.S. -cMS) were used for the study and potato starch was refered to them.The experiments were carried out concerning determination of reducing sugar as glucose and remaining Na-CNS and measurement of shift of the absorption maximum of the color of hydrolyzed product with iodine. The hydrolysis of L.D.S. -CMS was larger than H.D.S. -CMS, but less than starch in all cases. The result was seemed to be caused by carboxymethyl group.

Determination of Sodium Carboxymethylstarch in Ice Cream

Sodium carboxymethylstarch (Na-CMS) is permitted for the addition to foods below 2 per cent in our country, and it is often used as stabilizer in ice cream, but there is few reports on the determination of Na-CMS in foods, therefore we have studied on the determination of Na-CMS in ice cream.Na-CMS in ice cream was precipitated together with protein by addition of a mixture of hydrochloric acid and methyl alcohol (1: 5), the precipitate was dissolved in 0.1N scdium hydroxide solution and protein was digested with protease at 40°C after the pH of the soiution was adjusted to 7.5, and CMS was precipitated as copper compound from the digested solution. The copper compond was dissolved in 10% ammonium hydroxide solution, and the optical density of the colored solution which was produced with 0.1% anthrone in sulfuric acid, was measured at 625mμ.Na-CMS which was added together with sodium arginate in ice cream was determined as described above after sodium arginate was removed as insoluble free acid.When the mixed solution of Na-CMS and sodium arginate was heated in a water bath after acidified with sulfuric acid (pH 1.0-1.5), sodium arginate converted to insoluble free acid, whereas Na-CMS dissolved clearly.

Physiological Properties of Sodium Carboxymethyl Starch : : Two Figures

Physiological Properties of Sodium Carboxymethyl Starch : : Two Figures