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Background: Currently, many natural gums are extensively utilized as suspending agents in the formulation of pharmaceutical suspensions. They are easily available, nontoxic, biodegradable, and cost‐effective to be used as pharmaceutical excipients. Objective: The present study was aimed at physicochemical characterization and evaluation of the suspending capacity of Boswellia papyrifera gum (BPG) in comparison with sodium carboxy methyl cellulose (SCMC) and tragacanth gum (TG). Methods: The extracted and powdered BPG was subjected to physicochemical properties such as micromeritics, solubility, swelling power, ash value, moisture content, conductivity, pH, and apparent viscosity using standard methods. Metronidazole benzoate suspensions were formulated using various concentrations of BPG, SCMC, and TG (1%–5% w/v). The apparent viscosity, flow rate, sedimentation volume, redispersibility number, pH, and drug content were studied as assessment parameters. Results: The micromeritic studies revealed that BPG exhibited good flow properties. There was also a significant increase in solubility and swelling power of the gum as a function of temperature. The gum had 2.78% ash value and 4.32% moisture content. Conductivity and apparent viscosity of the gum were found to be increased with concentration (p < 0.05). However, the apparent viscosity of BPG was decreased with shear rate (p < 0.05), rendering a pseudoplastic flow property of the gum, which is an ideal characteristic of suspending agents. The suspending capacity of the BPG was found to be comparable to SCMC, but higher than TG. Thus, it can be concluded that BPG could be used as the best alternative to natural and synthetic suspending agents. [ABSTRACT FROM AUTHOR]

The transportation of coal-based solid waste filling slurry (CSWFS) through pipelines for underground goaf injection is essential for enhancing mine safety and promoting green, low-carbon coal mining. To address the issue of pipeline blockage caused by the suspension sensitivity of CSWFS during long-distance transportation, this study proposes the addition of the suspending agent hydroxypropyl methyl cellulose (HPMC) to transform the filling slurry into a stable suspending slurry. The mechanism by which the suspending agent modifies the rheological property of CSWFS was elucidated and verified. Firstly, an evaluation index system for the suspending state of CSWFS based on the "experimental test and theoretical calculation" was established. The values for layering degree, bleeding rate time-loss, and the corresponding average time-loss rate over 0 to 120 min of A1–A5 CSWFS were recorded as 24 mm–2 mm, 3.0–0.2%, 252.4–54.2%, and 149.6–14.6%, respectively. The concentration gradient evaluation result, C/CA = 0.91 (≥0.8), confirmed that the suspending agent maintained a stable suspending state over time for CSWFS. Secondly, it was demonstrated that the suspending agent HPMC modified the rheological property of A1–A5 CSWFS by increasing its plastic viscosity, which strengthened the viscous resistance to particle settling, thereby transforming a semi-stable slurry into a stable one. Additionally, the formation of a spatial suspending network by the suspending agent ensures that no pipeline blockage accidents occured in practical engineering applications. Furthermore, the XRD and SEM tests were utilized to verify the microstructure of the top (T) and bottom (B) samples in A4 block. It was concluded that the type of hydration products, occurrence forms, lapping compactness, and microstructural development were consistent, ultimately forming a high-strength, dense, hardened filling block. Finally, numerical simulation confirmed that the addition of suspending agent in A4 slurry formed a comprehensive spatial suspending network and a well-structured, unified system. This is one effective approach which could contribute to addressing the technical issue of pipeline blockage during long-distance pipeline transportation. [ABSTRACT FROM AUTHOR]

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The solubility is the preferential criteria for the medicament to show pharmacological action. A pharmaceutical suspension is a coarse dispersion of insoluble solid particle in a liquid medium. One of the best suitable dosage forms for people who cannot take solid dosage forms. It contain solvents, buffering agent, preservative, antioxidants, wetting agent, anti-foaming agent, suspending agent and flavouring agent. Suspension dosage form incorporate effective distribution of lipophilic drug; mask a bitter taste, avoid the use of cosolvents and provide resistance to deterioration of drug due to hydrolysis, oxidation or microbial activity. In addition, nanosuspension is the novel and recent advancement in enhancing aqueous solubility of weakly soluble drugs. It not only increases aqueous solubility but increases bioavailability as well. As a result of the significant improvement in bioavailability, the flexibility for surface modification and mucoadhesion for drug targeting have significantly expanded the scope of this novel formulation technology. Suspension allows for the absorption drug relatively higher than any other solution dosage forms. Different method of preparation are used with a solvent, suspending agent (HPMC and Methyl Cellulose) and Surfactant (Tween-80, and SLS). Introduction, preparation techniques, characterisation, and applications of the nano suspension are covered in this review article. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this work is to assess the suitability of Parkia biglobosa mucilage (PBM) as a suspending agent in metronidazole suspension. Methods and Materials: Metronidazole suspension was formulated with mucilage (0.1%, 0.5%, 1%, and 2% w/v) from P biglobosa seeds as the suspending agent. Similar suspensions of metronidazole that contained (0.1%, 0.5%, 1%, and 2% w/v) tragacanth or gelatin were also prepared for comparison to PBM-based formulations. The suspensions were assessed for rheological properties, sedimentation volume, degree of flocculation, ease of redispersion, flow rate (flowability), and drug-excipient compatibility using Fourier-transform infrared spectroscopy. Results: Brownish metronidazole suspensions with a smooth and elegant appearance were obtained. After 2 weeks of storage at ambient temperature (28 ± 2°C), the ease of redispersion was in the following order: tragacanth < PBM < gelatin-containing formulations. The optimal pH of the formulation was slightly acidic and did not significantly change (p > 0.05) after 3 months of storage at ambient temperature (28 ± 2°C). However, the viscosity of the formulations was reduced by more than 30%, and the flow rate was significantly increased (P < 0.05). Suspensions formulated with 2% PBM were well-flocculated and easily redispersible. Furthermore, the sedimentation volume and sedimentation rate of suspensions formulated with 2% PBM were comparable to that of tragacanth- and gelatin-containing suspensions. Conclusion: PBM hence has great promise as a suspending agent for pharmaceutical preparations. [ABSTRACT FROM AUTHOR]

Suspensions are two phase systems composed of solid materials dispersed in liquid. Detarium microcarpum gum (DMG) was obtained by acetone precipitation of filtrate obtained from maceration of Detarium microcarpum seed powder using distilled water. Ibuprofen was pulverized using a mortar and dispersed in distilled water to form ibuprofen suspension formulation (IS1). Five other ibuprofen suspension formulations were prepared using either DMG or acacia as the suspending agent (IS2-IS6). Benzoic acid was added during the preparation of formulations IS4 and IS6 as preservative. Physicochemical properties like pH, viscosity and the total microbial count for the suspensions were evaluated. Drug-excipient compatibility was studied using FTIR spectroscopy. The pH of the suspensions ranged from 3.7±0.0 -5.3±0.0 on day 0 to 3.9±0.0 - 6.3±0.0 on day 35. Flow rate was from 2.21±0.13 - 33.00±3.70 mls-1 on day 0 to 1.88±0.12 - 20.19±0.16 mls-1 on day 35. The viscosity at 25oC ranged from 2391.3 - 5702.2 mPas on day 0 to 3793.0 - 3828.2 mPas on day 35. It was a shear thinning system. Formulation IS6 was the most stable and IS1 was the least stable. The suspensions contained high level of bacteria on day 0 which increased significantly on day 35, with exception of formulations IS4 and IS6. Ibuprofen suspensions with good physicochemical properties were produced using DMG but the level of microbial contamination observed highlighted the need of having good environmental hygiene and use of preservatives when natural gums are used in formulations. [ABSTRACT FROM AUTHOR]

The objective of this investigation is to formulate reconstitutable indomethacin oral suspension as indomethacin dry syrup with co-processed composite of Zea mays husk cellulose and sodium carboxymethylcellulose for evaluation in indomethacin delivery. Pre-formulation studies were carried out on the Zea mays husk cellulose. Compatibility studies were carried out for the Zea mays husk cellulose and indomethacin. Dry syrup was formulated with composites of Avicel CE 15, Avicel HF E-102, Zea mays husk cellulose, and starch respectively in sodium carboxymethylcellulose. The dry syrups were reconstituted to suspension, and evaluated. The pre-formulation properties were within limits. FTIR result of Zea mays husk cellulose showed purity of cellulose. FTIR spectroscopy of Zea mays husk cellulose and indomethacin showed no interaction of cellulose with indomethacin. The release of indomethacin from reconstituted suspensions followed apparent (pseudo) first order kinetics, indicative of no reservoir entrapment, complexation, nor encapsulation of the active drug. With re-dispersion number of 3.47 ± 0.47, the re-dispersion of the reconstituted suspension, and other rheological properties were significantly (p < 0.5) improved by the Zea mays husk cellulose - sodium carboxymethylcellulose composite. It was found that Zea mays husk cellulose - sodium carboxymethylcellulose composite can substitute the standard suspending agent in formulation of reconstitutable indomethacin suspension based on its improved rheological, suspending and thixotropic properties. [ABSTRACT FROM AUTHOR]

In order to prepare detergents with high suspension ability, low viscosity, high transparency and low film-forming ability, two monomers of ethyl acrylate and methacrylic acid were used to prepare the polymer as the suspending agent in detergent (experimental group A). The influence of different monomer ratios on the suspension ability of the suspension agent was investigated. The viscosity and turbidity, suspension ability, film-forming ability and shear thinning ability in detergent of the experimental group A was compared with two commonly used acrylic suspension agents, namely Carbopol® Aqua SF-1 Polymer (control group B) and Carbopol® Aqua SF-2CN Polymer (control group C). The results show that the ductility in application of the experimental group A is the best due to the smallest viscosity in the same experimental conditions. When the mass fraction of the suspending agent is ≥1.8%, all three suspending agents have good transparency and suspending ability. The film forming ability of the experimental group A is the worst, therefore it is not easy to block the pump head. The spray extrusion strength and spray uniformity of the experimental group A are better than those of the control group B and the control group C. Overall, the performances of the experimental group A are the best. [ABSTRACT FROM AUTHOR]

The aim of the article was to obtain maximum information about plant mucilage, its sources and applications in the pharmaceutical industry. This study focuses on the scientific articles and books available in Internet resources and college library that deal with the sources, applications, extraction and isolation of plant mucilage. Mucilage is obtained mainly from plant sources and can be isolated easily. Due to the low cost, easy availability, non-toxicity, non-irritancy, and biocompatibility, mucilage is of great demand in the field of pharmaceuticals. Hibiscus rosa-sinensis L., Trigonella foenum-graecum L., Abelmoschus esculentus L, Plantago ovata Forssk. and Aloe barbadensis L. are some common sources of mucilage. The isolation methods vary depending on the part of the plant where mucilage is present. It is commonly used as gelling agent, suspending agent, binder, and disintegrant. Since it is hydrophilic in nature, chances of deterioration are higher. In this review, different mucilage sources and their isolation methods are discussed in detail. Mucilage is used as excipient in many formulations of tablets, suspensions, gels, etc. The study explores the potential of plant mucilage as an excipient in pharmaceutical formulations. The biodegradable and biocompatible properties of this inexpensive excipient make it more favourable for the newer formulation development. [ABSTRACT FROM AUTHOR]

The adsorption of polyvinylpyrrolidone (PVP) by the thermoregulating microcapsules has been studied. The mass ratio of PVP has been changed from 1 to 20, with respect to the lowest amount of PVP value (4.08 g). The results confirmed that a large amount of PVP was adsorbed by the polymeric shell. Experimental data were perfectly fitted by Langmuir model, obtaining at a confidence level of 95% values of 192.9 ± 0.4 g/kg and 0.18 ± 0.11 m/kg for the maximum adsorption capacity and the equilibrium constant, respectively. It was found that utilizing PVP, at a concentration of 5.03 wt% of the total mass provided optimum conditions for synthesizing thermoregulating microcapsules containing Rubitherm®RT27 from poly(styrene-divinylbenzene) (P(St-DVB)), with the best thermal and physical properties. Finally, the robustness of the process was checked at a large scale by using a reactor that maintains geometrical similarities with that used at laboratory scale. The thermal properties, the encapsulation efficiency, and the microcapsule yield were similar, but at pilot plant scale, narrower particle size distributions were obtained. [ABSTRACT FROM AUTHOR]

Introduction: Present work, is an effort toward exploring the potential of Cassia fistula Linn. seed gum as an extended release polymer and laxative. While, C. fistula pulp polymer has evaluated as suspending agent. Materials and Methods: For extended release application, total five batches (F1-F5) were prepared by varying the ratio of drug:polymer as 1:1, 1:2, 1:3, 1:4, and 1:5, respectively. The granules were prepared by wet granulation method and further evaluated for micromeritic properties such as angle of repose (θ), Carr's compressibility index (CCI), and Hausner's ratio. Further compacts were evaluated by hardness, thickness, swelling index, in-vitro dissolution, and so on. Laxative activity was evaluated by administration of seed polymer (100 mg/kg) alone or in combination with bisacodyl (2.5 mg/kg) in 1% Tween 80. Zinc oxide suspension was prepared by varying the concentration of C. fistula pulp polymer and compared with suspension made by use of tragacanth, sodium carboxymethyl cellulose and bentonite. Results: Result showed that granules were free flowing, while the compact extended the drug release up to 10 h (72.84 ± 0.98; batch F5) and followed Higuchi matrix release kinetics. This extended release might be due to the formation of polyelectrolyte complex because of gluco-mannose in seed gum. Result of in-vivo laxative activity showed that seed polymer reduced faeces weight after 24 h compared to control (P < 0.01). Conclusions: Pulp polymer showed good sedimentation volume, but alone fails to stabilize the suspension for a longer period, so it could be useful in combination with other suspending agents and can be useful as novel excipient. [ABSTRACT FROM AUTHOR]

An oral controlled release suspension of chlorpheniramine maleate was prepared using ion-exchange resin technology. A strong cation exchange resin Indion 244 was utilized for the sorption of the drug and the drug resinates was evaluated for various physical and chemical parameters. The drug-resinate complex was microencapsulated with a polymer Eudragit RS 100 to further retard the release characteristics. Both the drug-resinate complex and microencapsulated drug resinate were suspended in a palatable aqueous suspension base and were evaluated for controlled release characteristic. Stability study indicated that elevated temperature did not alter the sustained release nature of the dosage form indicating that polymer membrane surrounding the core material remained intact throughout the storage period. [ABSTRACT FROM AUTHOR]

Three sodium carboxymethyl mungbean starches (SCMMSs) were selected, based on the physicochemical profiles and evaluated as potential pharmaceutical suspending agent in comparison with a sodium carboxymethyl tapioca starch and other five commercial suspending agents. Ibuprofen suspension was employed as a model formulation with 0.5, 1.0, and 2.0% w/v of suspending agents. Evaluation parameters included the determination of sedimentation volume ratio, redispersibility, viscosity and rheological properties and content uniformity studies. The results revealed that a high-viscosity modified mungbean starch, MMS-M-04, possessed suitable properties as a suspending agent and, at 1% concentration, was as effective as sodium carboxymethylcellulose and xanthan gum, two most-commonly used suspending agents. This modified starch could be further developed and employed as a new commercial suspending agent in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

The synthesis of homo-polymers of acrylic acid and co-polymers of acrylic acid–methyl methacrylate as suspension agents (SA) was performed in aqueous media, and SA were used as stabilizer in the suspension polymerization of styrene. The behavior of water solutions in the interfacial tension of SA against styrene was studied. The composition of the co-polymers and their molecular weights are related to the Zykonski model coefficients and to the molecular configuration of the stabilizer at the interface. It was found that the molecular weight, the composition of SA, the concentration used in the reaction system and the time at which it was added had a marked effect on the stability of the suspension during the reaction and on the final particle size distribution of the polystyrene beads. The homo-polymers of acrylic acid do not prevent correctly the coalescence during the suspension polymerization, while the co-polymers of acrylic acid and methyl methacrylate are well adsorbed into the oil/water interface and then work as good stabilizers for styrene suspension polymerizations. Provided a good stabilizer was used, i.e., with a high molecular weight and enough hydrophobic character, its addition delayed up to the beginning of the sticky stage produced a quite narrow particle size distribution. [ABSTRACT FROM AUTHOR]