Spherical Agglomerates Research Articles

Evaluation of Remineralization Potential of Natural Substances on Artificially Induced Carious Lesions in Primary Teeth: An In Vitro Study.

To evaluate the remineralizing potential of natural substances on artificially induced caries lesions in primary teeth. A total of 50 primary molar teeth were selected and subjected to a demineralization process. Then samples were randomly divided into five groups for the remineralization process. Group I-colophony, group II-5% sodium fluoride (NaF) + colophony, group III-grape seed extract (GSE) + colophony, group IV-5% NaF + colophony + 10% peptide, and group V- GSE + colophony + 10% peptide. All the groups were subjected to remineralization using a brushing stimulator for 3,000 cycles. Assessment was done using Vickers hardness testing machine for evaluating the enamel surface microhardness (SMH) and scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) for evaluating the surface morphology and mineral content, before and after demineralization and after remineralization, the obtained data was analyzed statistically using IBM Statistical Package for the Social Sciences (SPSS) software version 25. The enamel microhardness results of this study revealed that remineralization of enamel was highest in group V (212.83 ± 64.416) and least in group II (137.83 ± 26.324) p-value of 0.038. SEM-EDX analysis revealed high calcium (Ca) and fluoride (F) content in groups II and IV, which was significant (p-value of 0.001) from other groups. Surface morphology evaluated with SEM revealed spherical globular agglomerates and scaffolding deposits on the enamel surface in groups III and V resembling the remineralization process. Grape seed extract (GSE) with colophony and peptide is a superior natural alternative to NaF. Colophony also exhibited remineralizing potential in primary enamel. Natural remineralizing agents like GSE, colophony, and its combination serves as a potential alternative to overcome the toxic effect on long-term usage of F. These natural substances can be applicable in clinical conditions by incorporating toothpaste and varnish, which can be used as an alternative or adjuvant to the topical application of F. Pooja V Ravi, Rajakumar S, Kavitha Ramar. Evaluation of Remineralization Potential of Natural Substances on Artificially Induced Carious Lesions in Primary Teeth: An In Vitro Study. Int J Clin Pediatr Dent 2023;16(2):244-250.

ONE POT DEVELOPMENT OF LIPID-BASED QUERCETIN SPHERICAL AGGLOMERATES FOR BIOAVAILABILITY ENHANCEMENT: IN VITRO AND IN VIVO ASSESSMENTS

Objective: Quercetin, a wonder flavanoid despite numerous pharmacological actions, has limited clinical applications due to solubility and permeability issues and additionally having shorter biological half-life. The goal of the current work was to design Quercetin lipid-based spherical crystals, to improve its oral bioavailability and sustain its in vivo plasma levels. Methods: An anti-solvent precipitation method was employed to prepare quercetin spherical agglomerates using ethanol and distilled water as good and bad solvents, respectively. As bridging liquid chloroform, dichloromethane, hexane and gelucire 43/01, compritol 888 as lipid carrier were screened. The drug-to-lipid polymer proportion and stirring speed effect were optimized by 3-level, 2-factor, experimental design. Numerical optimization function was employed to identify the optimum level of independent variables. Spectroscopic, micromeritic, surface morphology, size distribution, saturated solubility, in vitro dissolution, in vivo pharmackokinetic and stability studies were performed. Results: Surface morphology studies indicated the agglomeration of quercetin needle-like fragments into a spherical shape, which further showed smooth surfaces due to entrapment of QC in lipid carrier. The spherical agglomerates of quercetin showed a four-fold improvement in aqueous solubility compared to pure drug and showed 92.13% release in 8 h. The optimised formulation showed a 3.69-fold enhancement in relative bioavailability in contrast to the marketed preparation in an in vivo pharmacokinetic analysis in male Wistar rats. Conclusion: The obtained lipid-based spherical crystals of quercetin with enhanced bioavailability could be effectively used for its various potential pharmacological applications. The designed system can also be utilized to deliver other phytochemicals with poor bioavailability due to limited solubility and permeability.

Microparticulation of Levofloxacin HCl by Crystallo-co-agglomeration Technique

Particle engineering techniques have gained a unique place in the present pharma industry to improve physicochemical properties of the drugs. The aim of this research work was to formulate and evaluate directly compressible agglomerates of Levofloxacin HCl with a view to improve their micromeritic properties and thereby to reduce the cost of production. Fluoroquinolone anti-infective, is used to treat bacterial conjunctivitis, sinusitis, chronic bronchitis, community- acquired pneumonia and pneumonia caused by penicillin resistant strains of Streptococcus pneumonia. Some of the fluoroquinolone high dose’s exhibit poor compressibility and flow properties, hence may not be suitable candidate for direct compression process, but by applying the crystallo-co-agglomeration (CCA) technique, the attempt may be made to change the properties of these molecules to make them suitable candidates for direct compression. This investigation was aimed to utilize CCA process to develop spherical agglomerates of levofloxacin HCl in selected polymers in different ratio. The developed spherical agglomerates of levofloxacin HCl may exhibit improved micrometric and dissolution properties hence may be suitable for direct compression process. Results indicated that micromeritic, mechanical and compressional properties of the agglomerates were greatly influenced by nature and type of polymer incorporated. The mean release time, mean dissolution time, dissolution efficiency, Q30 and Q90 of the tablets prepared from agglomerates showed remarkable increase in CCA compared to tablets prepared by wet granulation. Observations also revealed that by varying the type and concentration of polymer, desired release rate can be obtained.

Spherical crystal agglomeration technique for improved flow properties and oral bioavailability of atazanavir sulphate.

Aim: The current research focused on formulation of spherical crystal agglomerates (SCA) of atazanavir sulphatefor improving flow property and solubility. Materials & methods: SCA were formulated by quasi-emulsification solvent diffusion. Methanol, water and dichloromethane were employed as a good solvent, bad solvent and bridging liquid respectively. Results & conclusion: SCA with improved solubility and micromeritic properties were directly compressed into a tablet. The SCA tablets had higher dissolution rates compared with plain drug and marketed product. Invivo pharmacokinetic studies revealed higher Cmax and AUC0-t of the SCA than marketed product with relative bioavailability of 1.74. The formulation was stable for more than 3months, with insignificant difference in % drug content and % drug dissolution.

Effect of silver oxide additives on structural, optical dispersion and protection features of lead boro-phosphate glasses

This work presents the structural, optical, refractive index dispersion, and shielding properties of Ag-containing lead-boro-phosphate glasses. The glasses were prepared using the classic melt-quenching method, in which the Ag2O concentration was varied in each synthesis. The precipitation of Ag NPs was proved by the appearance of the (200) crystal plane in the XRD patterns and confirmed by the homogeneous distribution of spherical agglomerates observed in TEM images. FTIR and Raman analyses have revealed a network depolymerization process resulting from the distortion of the PO4 units and the formation of Ag NPs. Therefore, the Ag ions contribute at high concentrations to an increase in the glass density and a reduction in the optical band gap energy. Ellipsometry parameters indicate that the glass becomes more optically dispersive due to the Ag NPs formation, which improves its performance for several potential applications in multi-functional optical devices. The mass attenuation factors are determined in the energy range of 15 keV–15 MeV and are very sensitive to the silver content at low energies. The Half value layer (HVL) decreases with the amount of Ag2O, indicating the improvement in the material's ability to attenuate radiation. The results show that the glass sample with the highest Ag content has the highest shielding effectiveness.

Spherical particles design of vanillin via crystallization method: Preparation, characterization and mechanism

Vanillin is a natural flavor and is widely used in the fields of medicine, food and optoelectronics. However, the stable form I of vanillin usually shows needle or fiber-like morphology during crystallization, and it has poor powder performance (flowability, bulk density, dissolution rate, etc.), which further limits its applications. In this work, to improve the powder performances of vanillin, the spherical crystals were designed and prepared via spherical agglomeration method, and the spherical particles were systematically characterized using polarized light microscopy (PLM), particle size instrumentation, powder X-ray diffraction (PXRD) and Fourier infrared transform spectroscopy (FTIR). Meanwhile, the effects of BSR (Vbridging liquid:Vsolute), agitation rate and surfactant on the morphology and particle size distribution of spherical particles were analyzed to determine the optimal operating conditions for the spherical crystallization of vanillin as well as its formation mechanism and to improve the powder performance of the products. In addition, the multicomponent spherical particles of vanillin-salicylic acid obtained by crystal co-agglomeration (CCA) meet the formulation requirements in terms of morphology and particle size, which also enhance the dissolution rate of vanillin.

Biodegradable silk fibroin scaffold doped with mineralized collagen induces bone regeneration in rat cranial defects

Compared with most nondegradable or slowly degradable bone repair materials, bioactive biodegradable porous scaffolds with certain mechanical strengths can promote the regeneration of both new bone and vasculature while the cavity created by their degradation can be replaced by the infiltration of new bone tissue. Mineralized collagen (MC) is the basic structural unit of bone tissue, and silk fibroin (SF) is a natural polymer with adjustable degradation rates and superior mechanical properties. In this study, a three-dimensional porous biomimetic composite scaffold with a two-component SF-MC system was constructed based on the advantages of both materials. The spherical mineral agglomerates of the MC were uniformly distributed on the surface and inside the SF skeleton, which ensured good mechanical properties while regulating the degradation rate of the scaffold. Second, the SF-MC scaffold had good osteogenic induction of bone marrow mesenchymal stem cells (BMSCs) and preosteoblasts (MC3T3-E1) and also promoted the proliferation of MC3T3-E1 cells. Finally, in vivo 5 mm cranial defect repair experiments confirmed that the SF-MC scaffold stimulated vascular regeneration and promoted new bone regeneration in vivo by means of in situ regeneration. Overall, we believe that this low-cost biomimetic biodegradable SF-MC scaffold with many advantages has some clinical translation prospects.

Improved Spherical Particle Preparation of Ceftriaxone Sodium via Membrane-Assisted Spherical Crystallization

Spherical drug particles prepared by the spherical crystallization technique can simultaneously improve the mobility of particles, mechanical properties, drug solubility and bioavailability, etc. However, high-efficient mixing of a solution and the formation of uniform bridging liquid droplets were crucial for accurate control of spherical crystallization processes. Herein, a novel membrane-assisted spherical crystallization (MASC) technology was proposed to produce monodisperse spherical agglomerates of ceftriaxone sodium. The poor solvent permeation rate of MASC was stabilized by adjusting the liquid flow velocity in the shell side and tube side. Uniform bridging liquid droplets constructed by a polytetrafluoroethylene hollow fiber membrane were observed in real time. A stable flow field and crystallization microenvironment were provided on the hollow fiber membrane surface. The crystal size distribution and the coefficient of variation of ceftriaxone sodium products were improved compared with those of conventional spherical crystallization (CSC) under the same stirring rate. The impurities of CSC products did not meet the requirements due to the degradation after 14 days’ acceleration experiment, while the one of MASC products still met the pharmacopoeia requirements after 30 days. This study provides a potential membrane-based technology for the enhancement of spherical crystallization of related drugs.

A review on spherical crystallization: A novel technique in the field of particle engineering

In the production of tablets, the direct compression method is mostly used. In comparison to the traditional wet granulation approach, this cannot be used with sensitive pharmaceuticals and also has a lot more processing limitations. Spherical agglomeration is a novel method for creating pharmaceutical dosage forms that are immediately compressible, the process of spherical agglomeration, which improves the powder's qualities such as particle size, shape, flow characteristics, solubility, and bioavailability of pharmaceutical medicinal ingredients, includes transforming tiny crystals into a spherical shape. The spherical crystallization was improved for use with hydrophilic polymers in order to improve the dissolution properties of pharmaceuticals that are poorly water-soluble. The flow characteristics, particle size analysis, compression, and dissolution behaviour of the spherical agglomerates were also improved. Wet spherical agglomeration (WSA) and the quasiemulsion solvent diffusion method (QESD) are the two most used methods for crystallizing spheres. Additionally, these approaches have two additions: the ammonia diffusion system (ADS) and crystallo-coagglomeration (CCA).The neutralization technique is another method used in this procedure. Any of the aforementioned methods can be employed simultaneously for both crystallization and agglomeration. The crystal physical characteristics, including their shape, polymorphism detection using x-ray powder diffraction (XRD), and thermodynamic characteristics using differential scanning calorimetry (DSC), were examined.

Analysis of the growth mechanism of hierarchical structure Ni0.8Co0.1Mn0.1(OH)2 agglomerates as precursors of LiNi0.8Co0.1Mn0.1O2 in the presence of aqueous ammonia

Hierarchical structure Ni0.8Co0.1Mn0.1(OH)2 agglomerates were formed by coprecipitation method in the presence of aqueous ammonia in a continuous stirred tank reactor (CSTR). The resultant spherical secondary particles are comprised of highly anisotropic primary grains as building blocks, which retain a distinct hexagonal flake morphology with six {010} equivalent crystal facets and two other {001} facets. The formation of hierarchical agglomerates typically undergoes three steps: (i) the formation of grain nuclei (homogeneous nucleation), (ii) anisotropic growth of grains and formation of hexagonal nanosheets, (iii) agglomeration of single crystal grains and formation and growth of spherical agglomerates. This unique hierarchical structures of Ni0.8Co0.1Mn0.1(OH)2 point to its promising applications in preparation of high-performance cathode materials for lithium-ion batteries.

SPHERICAL CRYSTALLIZATION: A TOOL TO IMPROVE SOLUBILITY OF DRUGS

Spherical crystallization is a technique in which crystallization and agglomeration are carried out synchronously in one step to form compact spherical form. The most common methods used in spherical agglomeration are quasi emulsion solvent diffusion method, ammonia diffusion system, neutralization technique and co-agglomeration. It succeeded to improve dissolution property of poorly soluble drugs. This can change drug powder properties such as flowability, wettability, packability, compressibility. It has wider applications in improvement of poorly compressible drugs; it has wider application in improvement of compressability of poorly compressible drugs, masking bitter taste of drugs, improving dissolution property, bioavailability and solubility of drugs. Agglomeration crystals converted into tablet forms thus helping us by saving time and reducing cost.

Processability and Oral Bioavailability Improvement of Itraconazole by Particle Engineering Technique.

The current study aimed to improve the processability and oral bioavailability of itraconazole (ITZ) via spherical agglomeration. ITZ-spherical agglomerates (ITZ-SA) and ITZ-poloxamer 407-spherical agglomerates (ITZ-PLX-SA) were optimized using Box-Behnken design. Here, the drug release was affected by polymer concentration and stirring speed, whereas particle size was altered by stirring speed, polymer concentration, and amount of bridging liquid. Heckel and Kawakita studies showed a reduction in mean yield pressure and remarkably lowered 1/b value than ITZ, indicating better compactibility and flowability of ITZ-PLX-SA. Physicochemical interactions were not observed during the process, as indicated by ATR-FTIR, DSC, and XRPD. The significant improvement in % drug release of ITZ-PLX-SA was attributed to better wettability and the presence of polymer than ITZ-SA and ITZ. The pharmacokinetic study in rats indicated fivefold enhanced Cmax and twofold improved AUC for ITZ-PLX-SA than plain drug. Thus, spherical agglomeration could improve overall processability and pharmacokinetic profile of ITZ.

Continuous Feeding and Blending Demonstration with Co-Processed Drug Substance

Continuous direct compression (CDC) of solid oral dosage forms requires materials exhibiting acceptable flow and compression properties. The desired active pharmaceutical ingredient (API) powder properties can be difficult to achieve through conventional particle engineering approaches, such as particle size and habit modification during crystallization. Co-processing of API with excipients can significantly improve the powder properties to overcome these difficulties. In this manuscript, performance of a co-processed API was evaluated in a continuous feeding and blending process using GEA ConsiGma® Continuous Dosing and Blending Unit (CDB1). The co-processed theophylline was generated via a methodology in which polymer was precipitated and coated the crystalline theophylline particles resulting in nearly spherical agglomerates. A range of drug loads (1-25% w/w), flow rates (15-40 kg/h) and blender speeds (220-400 rpm) were studied. The results demonstrated that the co-processed API can be successfully fed through a loss-in-weight feeder and blended with other excipients in a high shear blender to generate tablets with acceptable content uniformity at 1-25% w/w drug loads. This study supports that using co-processed API with enhanced powder properties is a promising approach to enable continuous manufacturing for APIs with challenging properties.

Influence of annealing on structural, morphology, magnetic and optical properties of PLD deposited CuFe2O4 thin films

• Successfully produced of CuFe 2 O 4 nanoparticles and prepared thin films which is grown on a glass substrate by pulsed laser deposition (PLD) technique. • The detailed structural properties of films are studied using experimental (XRD, FE-SEM, VSM, and Optical properties). • The magnetization and remanence of prepared samples have decreased with increased annealing substrate temperatures. • As per report the thin films have direct band gap energy; it reduces with increasing annealing temperature, which is due to improve the crystallinity. In this work, copper-ferrite (CuFe 2 O 4 ) nano-crystallite was synthesized by the gel method and deposited on a microscope glass substrate using a pulse laser deposition (PLD) technique at room temperature. The obtained deposited thin films were annealed at four different temperatures (200 °C, 300 °C, 400 °C, and 500 °C) for 4 hours in an air atmosphere. The structural, morphological, thermal, magnetic, and optical properties of the thin film samples were characterized using an X-ray diffractometer (XRD), Field emission scan electron microscopy (FE-SEM), thermogravimetric and differential thermal analysis (TG-DTA), Vibrating sample magnetometer (VSM) and Ultraviolet-Visible spectrophotometer (UV-Vis). X-ray diffraction patterns of the unannealed and annealed films show the presence of the anti-ferromagnetic (α-Fe 2 O 4 ) phase along with the single-cubic spinel structure phase. The grain sizes were found to have low crystalline copper ferrite with a mixture magnetic and hematite crystalline phases. With the decrease of the grain size and increasing of annealing substrate temperatures, the ratio of hematite to magnetite phases increased, and reached to an impure magnetite phase for the 6.35 nm grain. The morphological images obtained by transmission electron microscopy technique showed that the particle size of copper ferrite nanoparticles gradually became smaller from 10 nm to 5 nm. Surface morphology of all fabricated samples investigated by field emission scan electron microscopy technique exhibiting different sizes, almost spherical grains and agglomerates, which may be depending upon preparation method and substrate temperature. The correlation between structure and thermal stability of prepared materials was studied by (TG-DTA). With increasing of annealing substrate temperature from room temperature to 500 °C, the saturation magnetization (M s ) value decreased from 8.79 emu/g to 2.12 emu/g while the coercivity (H c ) value increased from 52.22 Oe to 91.26 Oe. The lowest widening of optical band gap in the copper ferrite film was 1.57 eV. The magnetic and the optical parameters suggested that these films are potential candidates for gas sensor applications.

Towards effective dye degradation and antimicrobial behavior of chitosan and C3N4-doped CdS nanoparticles

In this study, co-precipitation has been employed to develop carbon nitride (C 3 N 4 ) and chitosan (CS)-doped CdS nanoparticles (NPs) to investigate the doping effect of CS and C 3 N 4 on CdS to degrade MB dye and assess their antibacterial activity. Comparatively, the maximum dye degradation achieved by the previously reported binary blend of CdS-C 3 N 4 was 85%, whereas the maximum degradation achieved by the currently prepared ternary nano-catalyst was 99.75%. Furthermore, CdS NPs were doped with a fixed amount of CS at various concentrations (2 and 4 wt. %) of C 3 N 4 . Numerous techniques have been utilized to characterize doped NPs. The hexagonal phase of CdS was confirmed by XRD results, and doping caused a decrease in crystallite size, as calculated by the Debye Scherrer formula. Functional group existence was determined by FTIR; CdS was confirmed at 662 and 758 cm −1 , and doped CdS exhibited bond stretching and absorption at 1061, 1388, 1627, and 3434 cm -1 . The UV-Vis absorption spectra with blueshift after doping resulted in increased bandgap energy, which could be attributed to a reduction in crystallite size. PL spectra were utilized to observe the charge carrier transfer and trap sites of doped NPs. The presence of CdS formation and doping was observed using EDS. The morphology of the product was examined using HRTEM, which revealed spherical NPs agglomeration. C 3 N 4 -doped NPs demonstrated significant methylene blue (MB) dye degradation, while doped CdS samples exhibited considerable antimicrobial activity against Staphylococcus aureus and Escherichia coli bacteria.

AGLOMERATION OF Al2O3 NANOMETRIC AND SUBMICROMETRIC PARTICLES BY SPRAY DRYING FOR THEIR USE AS FEEDSTOCK IN THERMAL SPRAYING COATINGS

This study focuses on optimizing the parameters of the spray-drying process for the agglomeration of both nanometric and submicrometric Al2O3 particles for their use as feedstock to manufacture thermally sprayed coatings. Initially, for an aqueous suspension with submicrometric alumina particles, d10 = 0.8 to d90 = 2.0 µm, named SA, was evaluated the effect of: i) The solids percentage in the aqueous suspension, ii) the feed flow rate and iii) the hot air rate used to evaporate the water in the suspension, on the agglomeration efficiency and the morphology of agglomerated obtained, utilizing a factorial experimental design with three factors and two levels. The agglomeration efficiency was calculated as the ratio between the weight percentage of granulated particles and the weight of solids in the sprayed slurry, while the morphology was analyzed by scanning electron spectroscopy SEM. The agglomeration results for the SA suspension indicate that the highest efficiency was achieved with a solid percentage in an aqueous suspension of 30 wt. % (10 vol.%), a feed rate of 3.1 ml/min and a hot air rate of 5.5 m3/min at a temperature of 220 °C, obtaining spherical agglomerates. Nevertheless, different morphologies of agglomerate were obtained based on the others experimental runs, such as hollow spheres. Subsequently, these parameters were replicated for a suspension of alumina nanoparticles, d50=80 nm, called NA, to obtain granules with a spherical morphology, composed of primary and secondary agglomerates whose size distributions correspond to d10 = 5 to d90 = 11 µm and d10 = 30 to d90 = 44 µm, respectively, with a total granulation efficiency of 80%, of which, 90% have a suitable range size to be used as raw material in the production of coatings by means of thermal spraying.

Microbial biomineralization of hydroxyapatite nanocrystals using Bacillus tequilensis

In this research, biomimetic deposition of “bone-like” apatite by novel Gram-positive bacterium Bacillus tequilensis was investigated. Hydroxyapatite (HA) was produced by Bacillus tequilensis using defined biomineralization media and dried. Calcination was carried out at different temperatures (100 °C–900 °C) and HA nanopowder was analysed for its structural phase composition, crystallinity, crystallite size and functional groups. X-ray diffractometry (XRD) indicated that increasing temperatures increased the crystallinity of HA nanocrystals. The presence of carbonate groups was evidenced by Fourier transform infrared (FTIR) spectrum and the purity of synthesized apatite nanocrystals was validated by absence of secondary peaks in XRD studies. Scanning electron microscopy (SEM) images depicted those uniform spherical agglomerates of HA comprised of nanosized crystallites. Transmission electron microscope (TEM) results identified needle-like crystal morphologies with average dimensions of 30–60 nm length and 3–10 nm width. Rich trace ion deposition was illustrated by energy dispersive x-ray spectroscopy (EDS) and quantified using inductively coupled plasma optical emission spectrometer (ICP-OES). Overall, microbial biomineralization by Bacillus tequilensis produced nanocrystals of HA that mimicked “bone-like apatite” as evidenced by pure phase, B-type carbonated form, poor crystallinity and trace amounts of vital elements (Mg, Na, K, Zn, Sr, Cl). Moreover, in vitro cytotoxicity studies revealed more than 80% cell viability highlighting the biocompatible nature of synthesized nano HA. Thereby, Bacillus tequilensis biomineralized nano HA reflects as a suitable candidate for applications in biomedicine addressing bone injuries and aiding regeneration.

Enabling the drug combination of celecoxib through a spherical co-agglomeration strategy with controllable and stable drug content and good powder properties

Combining celecoxib with other chemopreventive drugs is a promising method of chemoprevention for cancer, especially for colorectal cancer. However, the traditional drug combination approaches are restricted with high-cost apparatus, complex and numerous unit operations. This work aims to develop an efficient spherical co-agglomeration strategy for celecoxib in combination with lovastatin, which can achieve drug combination in a single crystallization unit. The ternary solvent system was determined based on molecular simulation, and then a stable spherical agglomeration process was developed through the design of molar fraction of anti-solvent (MFA) and stirring rate to produce spherical agglomerates with high sphericity (84.2–89.9 %) and narrow size distribution. On this basis, celecoxib-benzoic acid spherical co-agglomerates were designed to form a complete spherical co-agglomeration strategy, which includes solvent system selection, spherical agglomeration and spherical co-agglomeration. Finally, celecoxib-lovastatin spherical co-agglomerates with synergistic efficacy were successfully produced by this strategy, with controllable and stable drug content (fluctuation < 2.7 %), good powder properties, and improved tabletability.

PREPARATION, CHARACTERIZATION, AND OPTIMIZATION OF MEBENDAZOLE SPHERICAL AGGLOMERATES USING MODIFIED EVAPORATIVE PRECIPITATION IN AQUEOUS SOLUTION (EPAS)

Objective: Mebendazole is a popular benzimidazole class anthelmintic drug useful in the treatment of main infections of threadworms as well as other less common worm infections like whipworm, roundworm, and hookworm in adults and children over 2 y of age. It is poorly soluble in water resulting in poor absorption from the intestinal tract leading to a decrease in bioavailability. Moreover, Mebendazole has poor flowability due to the needle-shaped crystals. This work was carried out with the aim of increasing the flowability and solubility of Mebendazole. Methods: A 32 full factorial design was used to investigate the effect of the concentration of Mebendazole and the quantity of water as an external phase using evaporative precipitation into an aqueous solution. The prepared agglomerates were characterized for particle size distribution, shape, Hausner ratio, Carr’s index and % dissolved in 60 min (C60). Results: The prepared agglomerates were found to be monodispersed. They also showed a decrease in the Hausner ration and Carr’s index, indicating improved flowability. Increase in C60 indicated that the agglomerates were found to have increased water solubility. Conclusion: Scanning Electron Microscopy showed that the agglomerates were spherical in shape. Fourier Transformed Infra-Red studies showed no chemical change in the prepared spherical agglomerates. Differential Scanning Calorimetry and X-ray diffraction studies showed an increase in amorphous characteristics of prepared spherical agglomerates. This method may be used for drugs with similar characteristics as Mebendazole.

Polypyrrole modified zirconium (IV) phosphate nanocomposite: An effective adsorbent for Cr(VI) removal by adsorption-reduction mechanism

A novel polypyrrole modified α-zirconium phosphate (PPY–ZrPO4) nanocomposite was synthesized by in situ oxidative polymerization method followed by the microwave irradiation process and then used for removal of hexavalent chromium. The physico-chemical properties of polypyrrole (PPY), α-zirconium phosphate (ZrPO4), and PPY-ZrPO4 were characterized by FTIR, XRD, Raman, Zeta potential, N2 adsorption-desorption isotherm, FESEM, TEM, TGA-DTA, and XPS techniques. The XRD data confirmed that our nanocomposite is crystalline in nature and the FTIR, Raman, and TGA data confirmed that organic PPY polymer interacts with ZrPO4 to form PPY-ZrPO4 nanocomposite. FESEM and TEM images of nanocomposite revealed that spherical PPY polymer agglomerate on the surface of ZrPO4 nanoparticles. The various adsorption parameters were optimized by batch adsorption experiment. The maximum removal of Cr(VI) (∼98.8%) occurred in 80 min of equilibrium time. The Cr(VI) adsorption followed the pseudo-second-order kinetic model and Langmuir isotherm model with a R2 value of 0.99 and a maximum adsorption capacity of 62.5 mg g−1. The thermodynamic data (ΔS = 0.102 kJ mol−1 K−1, ΔH = 29.35 kJ mol−1) revealed the spontaneity, endothermic nature, and feasibility of the adsorption process. XPS analysis indicated the simultaneous adsorption of Cr(VI) and in situ chemical reduction to less toxic Cr(III). The –N = and –NH– groups present on the surface of the material were responsible for in situ chemical reduction. Reusability studies showed a greater removal efficiency of ∼80% even after five adsorption-desorption cycles. Hence, the PPY-ZrPO4 nanocomposite could be used as a promising adsorbent for the removal of Cr(VI) from water.