FORMULATION AND INVITRO EVALUATION OF SOLID DISPERSION TABLETS OF SILYMARIN

Objective: The research aims to formulate and evaluate Solid Dispersion tablets of Silymarin. Methods: Solid dispersions of Silymarin were prepared with various concentrations of carriers by using solvent evaporation method. The prepared solid dispersions were compressed into tablets by using 8 mm punch rotary tablet punching machine, with the hardness of 3.5kg /cm2.The formulated tablets were evaluated for various quality control parameters. Results: Silymarin was mixed with various proportions of excipients which showed no drug-excipients interactions. The precompression blend of Silymarin solid dispersions were characterized with respect to angle of repose, bulk density, tapped density, Carrs index and Hausners ratio. The precompression blend of all the batches indicated good to fair flowability and compressibility. Conclusion: The tablet passed all the tests. Among all the formulations F4 formulation containing, Drug and PEG 4000 in the ratio of 1:4 showed good result that is 94.95 % in 60 minutes. As the concentration of polymer increased the drug release was increased. While the formulations containing PEG 6000 showed less release. Hence from the dissolution data it was evident that F4 formulation is the better formulation.

Improving Tableting Performance of Lactose Monohydrate by Fluid-Bed Melt Granulation Co-Processing

Co-processing is commonly used approach to improve functional characteristics of pharmaceutical excipients to become suitable for tablet production by direct compression. This study aimed to improve tableting characteristics of lactose monohydrate (LMH) by co-processing by fluid-bed melt granulation with addition of hydrophilic (PEG 4000 and poloxamer 188) and lipophilic (glyceryl palmitostearate) meltable binders. In addition to binding purpose, hydrophilic and lipophilic excipients were added to achieve self-lubricating properties of mixture. Co-processed mixtures exhibit superior flow properties compared to pure LMH and comparable or better flowability relative to commercial excipient Ludipress®. Compaction of mixtures co-processed with 20% PEG 4000 and 20% poloxamer 188 resulted in tablets with acceptable tensile strength (>2 MPa) and good lubricating properties (ejection and detachment stress values below 5 MPa) in a wide range of compression pressures. While the best lubricating properties were observed when glyceryl palmitostearate was used as meltable binder, obtained tablets failed to fulfil required mechanical characteristics. Although addition of meltable binder improves interparticle bonding, disintegration time was not prolonged compared to commercial excipient Ludipress®. Co-processed mixtures containing 20% of either PEG 4000 or poloxamer 188 showed superior tabletability and lubricant properties relative to LMH and Ludipress® and can be good candidates for tablet production by direct compression.

Influência polimérica na redução de arrasto em fluxos internos turbulentos em tubos de cloreto de polivinila (PVC)

As perdas por atrito representam um importante do custo no caso de aviões e navios, assim como também nos submarinos e em dutos de transporte para longas distâncias. As crises políticas e financeiras em torno do mundo e o aumento do preço do barril de petróleo tem impulsionado o estudo da redução de arrasto (RA) em dutos. Este trabalho tem por objetivo estudar a influência polimérica na RA em fluxos internos turbulentos. Os polímeros selecionados para o estudo foram o polietilenoglicol 4000 (PEG 4000), o Polyox WSR N60K, Polyox WSR 301 e Polyox WSR 205. Os polímeros redutores de arrasto são investigados a partir da análise de fluxo turbulento, com variação do número de Reynolds (Re) e concentrações. As concentrações poliméricas trabalhadas foram: 5, 10, 30, 50 e 100 ppm. Os resultados foram submetidos a análise de variância (ANOVA) e quando significativos ao teste de Tukey (95% de significância). A obtenção da RA se deu mediante do diferencial de pressão medido entre dois pontos estabelecidos. O Polyox WSR N60K, o Polyox WSR 301 e o Polyox WSR 205 tiveram resultados satisfatórios, com destaque para o Polyox WSR 301 que apresentou 28,88% de RA na concentração de 100 ppm.

Brushite bone cement containing polyethylene glycol for bone regeneration

BACKGROUND: Bone cements aid in bone regeneration; however, if the handling time is not well established for the material to harden, complications may arise. OBJECTIVE: This work investigates the effect of using polyethylene glycol (PEG) and characterize it in brushite bone cement in order to obtain desirable handling times as well as its regeneration in vivo to analyse if addition of this polymer may significantly modify its properties. METHODS: PEG 4000 was synthesised with wollastonite by phosphorization reaction in order to form brushite which was further cured by oven drying. They were further characterised and tested in vivo as tibial bone defect model using rabbits. RESULTS: Addition of PEG exhibited handling times of 60 min with a low increase in temperature when curing. Brushite phase of ∼71% was obtained after cement hardening with good compressive strength (25 MPa) and decent values of porosity (33%). In vivo presented that, at 40 days postoperatively, accelerated bone neoformation with partial consolidation at 30 days and total after 60 days when using bone cement. CONCLUSIONS: Addition of PEG does not disrupt the beneficial properties of the bone cement and can be a potential alternative for control the time-temperature profile of hardening these materials.

USE OF POLYETHYLENE GLYCOL (PEG, CARBOWAX) AS AN EMBEDDING MEDIUM PRODUCES RESULTS COMPARABLE TO PARAFFIN

Polyethylene glycol (PEG) is a non-carcinogenic, water-soluble polymer of ethylene oxide that has found wide applicability in industry and medicine, and has been used to embed and section small animal and plant tissues. Here we investigate the use of PEG for the rapid embedding of larger plant tissues. Ovaries of Musa velutina, Heliconia psittacorum and eight other species were embedded with a mixture of PEG 1450 and PEG 4000. It was found that tissues up to 6.5 × 10 mm could easily be embedded and sectioned in PEG. Embedded tissues could be stored at room temperature for up to 5 days with no detrimental effects. Sections were easily cut at 8–15 μm on a rotary microtome. PEG embedding resulted in equal or better tissue differentiation, better retention of cell inclusions, and reduced shrinkage compared with paraffin embedding. The process was also faster, requiring only 3–6 h compared with the 2 days needed for paraffin embedding. PEG is a rapid-embedding medium suitable for use with even large plant tissues.

Enrichment of aqueous solubility and dissolution profile of mesalamine: In vitro evaluation of solid dispersion

The aim of the present study was to formulate solid dispersion (SD) of Mesalamine to enrich the aqueous solubility and dissolution rate. Mesalamine is used in the management of acute ulcerative colitis and for the prevention of relapse of active ulcerative colitis. In the present study, Solid dispersion of Mesalamine was prepared by Fusion and Solvent evaporation method with different polymers. SD’s were characterized by % practical yield, drug content, Solubility, FT-IR, PXRD (Powder X- ray diffractometry), SEM (Scanning electron microscopy), in vitro dissolution studies and Stability studies. The percent drug release of prepared solid dispersion of Mesalamine by fusion and solid dispersion method (FM47, FM67, SE47 and SE67) in 1:7 ratio was found 81.36±0.41, 86.29±0.64, 82.45±0.57and 87.25±1.14 respectively. The aqueous solubility and percent drug release of solid dispersion of Mesalamine by both methods was significantly increased. The PXRD demonstrated that there was a significant decrease in crystallinity of pure drug present in the solid dispersions, which resulted in an increased aqueous solubility and dissolution rate of Mesalamine.The significant increase in aqueous solubility and dissolution rate of Mesalamine was observed in solid dispersion as the crystallinity of the drug decreased, absence of aggregation and agglomeration, increased wetability and good dispersibility after addition of PEG 4000 and PEG 6000.

Effect of Ground Vulcanizate Modification Methods on Properties of Oil-Petroleum-Resistant Rubber

In this paper, the influence of the modification method applied to ground vulcanizate (GV) on the properties of elastomeric compositions based on nitrile rubber is discussed. Modified GV has been mixed with the elastomeric composition, which is used for the manufacturing of oil-petroleum-resistant rubber products.The work takes into consideration two types of GV with different chemical nature. The first GV type is rubber crumb produced from end-of-life tires. The second GV type was obtained from rubber wastes based on nitrile rubber. Three methods of the modification are compared in the research: mechanical activation in a planetary ball mill, swelling in a Polyethylene glycol (PEG-400) medium, and the mechano-chemical transformation of GV with PEG-4000. It is shown that depending on the dosage addition of GV modified with PEG-4000 reduce the compression set up for (16.1±0.7%), the strength decreases only by 2.1–8.3%, and the elongation at break increases by 0.8–10.3% compared to rubber without additives.

Effect of Different Molecular Weight and Concentration of Polyethylene Glycol (PEG) on Tensile and Morphology of Sago Starch Film

Sago starch is a seasonal based plantation and widely found in Asia country. Its application mainly in cooking such as biscuits and as a thickener in jellies. To further utilize its application, bioplastic from sago starch was developed. In this study, sago starch films were prepared through a blending and casting method using polyethylene glycol (PEG) as a plasticizer by varying its molecular weights and concentrations. The interaction between starch and PEG in the blend was studied using FTIR technique. The effect on transparency, tensile stress, Young’s modulus as well as elongation percentages of the films was also examined. The results suggested that the addition of low molecular weight PEG (400 g.mol-1) increased the tensile stress of sago films from 33.51 MPa up to 39.11 MPa. Nevertheless, incorporation of high molecular weight of PEG (4000 g.mol-1) decreased the tensile strength of the film. Tensile strength and elongation at break of sago films increased with increasing of PEG concentration up to 2% and decreased with further increased of PEG content. Results indicated that there was a miscibility between these two components.

Promelaxin Microenemas Are Non-inferior to Oral Polyethylene Glycol for the Treatment of Functional Constipation in Young Children: A Randomized Clinical Trial

Background: Polyethylene glycol (PEG) is recommended as first-line treatment of pediatric functional constipation. However, the oral route of administration is often poorly feasible in children mostly due to poor palatability. Promelaxin microenemas exert a topical evacuative action and may offer a valuable option in pediatric FC.Aim: To assess whether Promelaxin microenemas would be non-inferior to PEG 4000 in young children with FC.Methods: This is a randomized, open-label, multi-centric, non-inferiority trial enrolling infants and young children aged 6–48 months, with FC according to Rome III criteria. After 1 week of run in, children were randomized to 2 weeks of Promelaxin or PEG, followed by a 6-week on-demand treatment period. Primary endpoint was response rate to randomized treatment, with “response” defined as at least 3 evacuations per week and an average increase of at least one evacuation per week as compared to baseline. Safety, stool consistency and the analysis of fecal microbiota were secondary endpoints.Results: Out of the 158 patients who entered the trial, 153 patients were treated (77 and 76, PEG and Promelaxin arm, respectively). In the primary analysis, the 95% confidence interval (CI) for the treatment's effect lay entirely above the non-inferiority margin in both Full Set (FAS) and Per Protocol (PP) analyses, providing evidence of the non-inferiority of Promelaxin vs. PEG 4000 [response rate difference: 16.5% (CI 1.55–31.49%) and 11.03% (CI −5.58 to 27.64%), FAS and PP analyses, respectively]. Mean compliance to the randomized treatment was >80% in both arms. Secondary endpoints did not significantly differ between the two arms, except for the average number of total days of on-demand treatment that was significantly lower in the Promelaxin arm [14.6 (12.7) vs. 9.8 (9.1), mean (SD); primary endpoint responders in PEG and Promelaxin arm, respectively; p = 0.027]. Microbiota evenness significantly increased in the PEG 4000 arm at V4 as compared to the Promelaxin arm (p < 0.05). In addition, at V5, patients treated with PEG showed a significantly decreased microbiota density as compared to patients treated with Promelaxin (p = 0.036).Conclusions: Promelaxin microenemas are non-inferior to oral PEG in children with FC.Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT02751411.