Search

In this work, the ability of calcium, magnesium, and zinc stearates to oxidative destruction of polyethylene was studied. For comparison, the samples of pure polyethylene and polyethylene with the commercial additive D2W were selected. Infrared spectroscopy data showed that samples with magnesium stearate accumulated double carbon bonds after 96 h of exposure in a climate chamber. In samples with zinc stearate, an asymmetric vibrations of COO groups disappear after 192 h of exposure in a climate chamber. All samples accumulated carbonyl groups resulting from polymer chain scission. After 96 h of aging, the sample with calcium stearate showed better oxidizing properties compared to other stearates. Mechanical test data also confirms the conclusion that the sample with calcium stearate is more susceptible to oxidative degradation among the studied stearates. [ABSTRACT FROM AUTHOR]

AbstractThis work aimed to select tablet diluent of Boesenbergia rotunda (L.) Mansf. extract tablet. Three tablet diluents, including microcrystalline cellulose (MCC), spray-dried rice starch, and spray-dried lactose were used. MCC exhibited superior performance to the other diluents by providing the hardest tablet, the lowest friability, and the shortest disintegration time. The Box-Behnken design was used to evaluate the effect of hydrophobic excipients when MCC was used as diluent. The optimal formulation was composed of fumed silica 1%, magnesium stearate 1%, and talcum 2%. The tablets had suitable hardness, low friability, and short disintegration time. The marker pinocembrin could be dissolved by 82% within 4 h. Although the marker decreased after three months of stability testing, the antioxidant activity of the formulation remained. In conclusion, MCC was shown to be superior to the other diluents, and the optimal formulation could be used to prepare Boesenbergia rotunda (L.) Mansf. extract tablet as a food supplement.

Agglomerate formulations for dry powder inhalation (DPI) formed with fine particles are versatile means for the highly efficient delivery of budesonide. However, uncontrolled agglomeration induces high deposition in the upper airway, causing local side effects due to high mechanical strength, worse deagglomeration, and poor fine-particle delivery. In the present study, fine lactose was mechanically dry-coated prior to particle agglomeration, and the agglomerates were then spheroidized via ultrasonic vibration to improve their aerosol performance. The results showed that the agglomerate produced with the surface-enriched hydrophobic magnesium stearate and ultrasonic vibration demonstrated improved aerosolization properties, benefiting from their lower mechanical strength, less interactive cohesive force, and improved fine powder dispersion behavior. After dispersion utilizing a Turbuhaler® with a pharmaceutical cascade impactor test, a fine particle fraction (FPF) of 71.1 ± 1.3% and an artificial throat deposition of 19.3 ± 0.4% were achieved, suggesting the potential to improve the therapeutic outcomes of budesonide with less localized infections of the mouth and pharynx. [ABSTRACT FROM AUTHOR]

This work aimed to select tablet diluent of Boesenbergia rotunda (L.) Mansf. extract tablet. Three tablet diluents, including microcrystalline cellulose (MCC), spray-dried rice starch, and spray-dried lactose were used. MCC exhibited superior performance to the other diluents by providing the hardest tablet, the lowest friability, and the shortest disintegration time. The Box-Behnken design was used to evaluate the effect of hydrophobic excipients when MCC was used as diluent. The optimal formulation was composed of fumed silica 1%, magnesium stearate 1%, and talcum 2%. The tablets had suitable hardness, low friability, and short disintegration time. The marker pinocembrin could be dissolved by 82% within 4 h. Although the marker decreased after three months of stability testing, the antioxidant activity of the formulation remained. In conclusion, MCC was shown to be superior to the other diluents, and the optimal formulation could be used to prepare Boesenbergia rotunda (L.) Mansf. extract tablet as a food supplement. [ABSTRACT FROM AUTHOR]

Punch sticking is a recurrent problem during the pharmaceutical tableting process. Powder moisture content plays a key role in the buildup of sticking; it evaporates due to increased tablet temperature, accumulates at the punch–tablet interface, and causes sticking through capillary force. This study investigated the effects of compaction pressure (CP), compaction speed (CS), and lubrication level (magnesium stearate (MgSt) ratio) on tablet surface temperature (TST) and tablet surface moisture content (TSMC). TST and TSMC were measured with an infrared thermal camera and near-infrared sensor, respectively. Microcrystalline cellulose was used as the tableting powder and MgSt as the lubricant. The low range of CS values (16–32 mm/s) considered in this study did not have significant effects on TST and TSMC. MgSt ratio had a significant positive effect on TST; this may be explained by the increase in powder blend effusivity with the addition of MgSt. However, MgSt ratio did not have a significant effect on TSMC. CP had a significant positive effect on both TST and TSMC. Increased CP induced higher heat generation through particle deformation and friction during the compaction phase, leading to increased TST. Furthermore, the water vapor diffusion rate through the powder bed might have increased due to the rise in thermal energy and led to further moisture accumulation at the tablet–punch interface, causing the significant positive effect of CP on TSMC. This result may explain the occurrence of sticking regardless of the CP applied during the tableting process. [ABSTRACT FROM AUTHOR]

Magnesium stearate (MgSt) is one of the most widely used solid lubricants in oral solid dosage forms. However, MgSt can negatively impact the tablets, decreasing their mechanical properties and lengthening disintegration/dissolution times. The aim of the present study was to compare the effect of MgSt and Sodium Stearyl Fumarate (SSF) lubricants on the physical characteristics of immediate release caffeine tablets compressed using granules of different sizes. Overall, the results demonstrate that using SSF as a lubricant significantly enhances tablet mechanical strength and reduces disintegration/wetting times for all granule sizes used to compress tablets. With smaller granules, SSF tends to be more effective. Over-lubrication with SSF leads to a decrease in tablet hardness as well, though to a significantly lesser extent than over-lubrication with MgSt.

This research sought to optimize the microwave-assisted extraction of Chatuphalathika as an herbal recipe maximizing the active compounds and the antioxidant activity by the Box–Behnken design. Three factors—microwave power, time, and cycle—were varied. Eight responses—extraction yield, total phenolic content, gallic acid content, corilagin content, chebulagic acid, chebulinic acid, IC50 from DPPH assay, and IC50 from FRAP assay—were monitored. Furthermore, cytotoxicity was evaluated to ensure the safety of the extract. After that, the optimized extract was compressed into tablets. The results showed that the optimal condition of the microwave-assisted extraction gave the simultaneous maximum extraction yield, total phenolic content, and antioxidant activity with a microwave power of 450 W for 30 s and 3 cycles. The extract obtained from the optimal condition exhibited a good safety profile although a concentration of 5 mg/mL was used. The optimized tablets were achieved when a compression force of 1500 psi and magnesium stearate of 1% were applied, and no sodium starch glycolate was added. In conclusion, the optimal green extraction method could be used for the extraction of the Chatuphalathika. Furthermore, the fabrication of Chatuphalathika tablets was successful, as the tablets had low friability with a short disintegration time. [ABSTRACT FROM AUTHOR]

An alternative to the time-consuming and error-prone pharmacopoeial gas chromatography method for the analysis of fatty acids (FAs) is urgently needed. The objective was therefore to propose a robust liquid chromatography method with charged aerosol detection for the analysis of polysorbate 80 (PS80) and magnesium stearate. FAs with different numbers of carbon atoms in the chain necessitated the use of a gradient method with a Hypersil Gold C18 column and acetonitrile as organic modifier. The risk-based Analytical Quality by Design approach was applied to define the Method Operable Design Region (MODR). Formic acid concentration, initial and final percentages of acetonitrile, gradient elution time, column temperature, and mobile phase flow rate were identified as critical method parameters (CMPs). The initial and final percentages of acetonitrile were fixed while the remaining CMPs were fine-tuned using response surface methodology. Critical method attributes included the baseline separation of adjacent peaks (α-linolenic and myristic acid, and oleic and petroselinic acid) and the retention factor of the last compound eluted, stearic acid. The MODR was calculated by Monte Carlo simulations with a probability equal or greater than 90%. Finally, the column temperature was set at 33 °C, the flow rate was 0.575 mL/min, and acetonitrile linearly increased from 70 to 80% (v/v) within 14.2 min. [ABSTRACT FROM AUTHOR]

Mixing/blending is a crucial operation in the manufacturing of solid drug products in the pharmaceutical industry. Although usually described and controlled in specific steps, blending is also inherent to other operations such as the transference of materials and equipment feeding systems. This study aimed to investigate a simple and fast wettability testing procedure capable to foresee the potential over-blending effects of lubricants occurring during the manufacturing of solid dosage forms. An industrial batch blend was submitted to two mixing mechanisms studies (diffusion and shear) during increasing time periods, and the developed wettability testing procedure was applied to assess their impact on blend water uptake. Capsules filled with these blends were tested for dissolution and disintegration. The method was applied to capsules with known dissolution results manufactured at an industrial scale. Results demonstrated that processes inducing shear stress led to less permeable blends with consequent retardation on capsules dissolution of at least 35% in the tested timepoints and obtained study metrics above 500 s. Moreover, disintegration testing was not able to detect non-compliant dissolutions, while the proposed wettability testing procedure proved to be able to identify performance failures. Wettability results correlate the effect of mixing mechanisms to capsules dissolution performance, evidencing that this technique can be applied in the pharmaceutical industry to evaluate possible over-blending effects. [ABSTRACT FROM AUTHOR]

Agglomerate formulations for dry powder inhalation (DPI) formed with fine particles are versatile means for the highly efficient delivery of budesonide. However, uncontrolled agglomeration induces high deposition in the upper airway, causing local side effects due to high mechanical strength, worse deagglomeration, and poor fine-particle delivery. In the present study, fine lactose was mechanically dry-coated prior to particle agglomeration, and the agglomerates were then spheroidized via ultrasonic vibration to improve their aerosol performance. The results showed that the agglomerate produced with the surface-enriched hydrophobic magnesium stearate and ultrasonic vibration demonstrated improved aerosolization properties, benefiting from their lower mechanical strength, less interactive cohesive force, and improved fine powder dispersion behavior. After dispersion utilizing a Turbuhaler® with a pharmaceutical cascade impactor test, a fine particle fraction (FPF) of 71.1 ± 1.3% and an artificial throat deposition of 19.3 ± 0.4% were achieved, suggesting the potential to improve the therapeutic outcomes of budesonide with less localized infections of the mouth and pharynx.

[Display omitted] Orodispersible minitablets (ODMTs) offer several benefits like easy swallowability, dose flexibility and simple manufacturing through direct compression. In this study, the effect of lubrication on five different co-processed excipients (Ludiflash®, Parteck® ODT, Prosolv® ODT G2, galenIQ™ 721 and SuperTab® 50 ODT) has been studied for orodispersible tablets (ODTs) with 11.28 and 2 mm in diameter. External lubrication was compared with internal lubrication using 0.5 %, 1 % or 2 % magnesium stearate or 1 %, 2 % or 4 % sodium stearyl fumarate. Mechanical strength and disintegration time of the ODTs were evaluated beside the lubrication efficiency. Especially mannitol-based co-processed excipients show strong dependency of the lubricant concentration whereas both ODTs and ODMTs and minitablets with isomalt showed comparable properties for both lubricants and their concentrations. Sodium stearyl fumarate is considered as the preferred lubricant for ODMTs as it showed a higher lubrication efficiency and less negative impact on disintegration time. External lubrication exhibited higher tensile strength for plastic materials, but increased the disintegration time, particularly for ODMTs due to the high specific surface where the lubricant is applied. In general, this study has demonstrated that minitablets require higher lubricant concentrations than conventionally sized tablets. [ABSTRACT FROM AUTHOR]

Seed pelleting is among the important types of seed coating. Compared with conventional seed coating, seed pelletization not only changes the seed shape and standardizes the seed appearance but also carries a larger amount of active ingredients with better compatibility. In this study, the irregular welsh onion (Allium fistulosum L.) seeds were pelletized, the performances of different fillers and binders for seed pellet granulation were investigated, and the microstructures of the prepared pellets with the optimized formulations were characterized. The results showed that the application of magnesium stearate mixed with talcum powder at a mass ratio of 1:2 as a filter and 1% CMC solution as a binder was favorable for the pelletizing of welsh onion seeds. The pelleted seeds were qualified in all indexes and met the standards of seed pelletization. The SEM observations of microstructures showed that there are significant differences among the pellets prepared by different fillers, and the tighter the bonding between fillers, the greater the strength of the pellets. The quality assessment of the pelletized seeds with pesticides showed that the reasonable addition of appropriate pesticides had little effect on seed germination. This study enriches the basic theory of seed pelleting via the combined evaluation of macroscopic properties and microstructures and provides a useful guideline for the improvements of precision sowing and standardized planting. [ABSTRACT FROM AUTHOR]

[Display omitted] Limited attempts have been made previously to develop high-loading CBD inhalable powders, which are essential for high dose delivery. Therefore, this study aimed to develop and characterise inhalable powders with ≥ 95 % w/w CBD by wet ball milling. The effects of magnesium stearate (2 % and 5 %) and inhaler resistance (low-resistance and high-resistance RS01 inhalers) on aerosol performance were also compared. Wet ball milling produced CBD powders with > 50 % production yield. The milled particles showed irregular shapes. The powders were crystalline with minimal amorphous content, low residual solvent level (<1%), and low moisture sorption (<4%). Magnesium stearate improved both the emitted and fine particle fractions. The aerodynamic particle size distribution of the formulations differed between the low-resistance and high-resistance RS01 inhalers. The latter decreased throat deposition but increased inhaler retention. The dissolution profiles showed that all three formulations released CBD steadily and plateaued at 30 min. The best scenario was CBD with 5 % magnesium stearate dispersed from the high resistance RS01 inhaler, showing the highest FPF with the lowest throat deposition. This combination may be tested in vivo in the future to investigate its pharmacokinetic profile. [ABSTRACT FROM AUTHOR]

This research sought to optimize the microwave-assisted extraction of Chatuphalathika as an herbal recipe maximizing the active compounds and the antioxidant activity by the Box–Behnken design. Three factors—microwave power, time, and cycle—were varied. Eight responses—extraction yield, total phenolic content, gallic acid content, corilagin content, chebulagic acid, chebulinic acid, IC50 from DPPH assay, and IC50 from FRAP assay—were monitored. Furthermore, cytotoxicity was evaluated to ensure the safety of the extract. After that, the optimized extract was compressed into tablets. The results showed that the optimal condition of the microwave-assisted extraction gave the simultaneous maximum extraction yield, total phenolic content, and antioxidant activity with a microwave power of 450 W for 30 s and 3 cycles. The extract obtained from the optimal condition exhibited a good safety profile although a concentration of 5 mg/mL was used. The optimized tablets were achieved when a compression force of 1500 psi and magnesium stearate of 1% were applied, and no sodium starch glycolate was added. In conclusion, the optimal green extraction method could be used for the extraction of the Chatuphalathika. Furthermore, the fabrication of Chatuphalathika tablets was successful, as the tablets had low friability with a short disintegration time.

An alternative to the time-consuming and error-prone pharmacopoeial gas chromatography method for the analysis of fatty acids (FAs) is urgently needed. The objective was therefore to propose a robust liquid chromatography method with charged aerosol detection for the analysis of polysorbate 80 (PS80) and magnesium stearate. FAs with different numbers of carbon atoms in the chain necessitated the use of a gradient method with a Hypersil Gold C18 column and acetonitrile as organic modifier. The risk-based Analytical Quality by Design approach was applied to define the Method Operable Design Region (MODR). Formic acid concentration, initial and final percentages of acetonitrile, gradient elution time, column temperature, and mobile phase flow rate were identified as critical method parameters (CMPs). The initial and final percentages of acetonitrile were fixed while the remaining CMPs were fine-tuned using response surface methodology. Critical method attributes included the baseline separation of adjacent peaks (α-linolenic and myristic acid, and oleic and petroselinic acid) and the retention factor of the last compound eluted, stearic acid. The MODR was calculated by Monte Carlo simulations with a probability equal or greater than 90%. Finally, the column temperature was set at 33 °C, the flow rate was 0.575 mL/min, and acetonitrile linearly increased from 70 to 80% (v/v) within 14.2 min.

This work presents a grinding process of monoammonium phosphate (MAP) as an active component in a powder fire extinguisher (PFE). The aim was to determine the grinding time for reaching the optimal particle size of MAP necessary for permanent fire extinguishing. MAP grinding was performed by using a laboratory ceramic ball mill and a vibrating cup mill. The grinding process was controlled by sieving using a 100 μm sieve at precisely defined time intervals. The efficiency of a PFE depends on the share of the -100 μm fraction of the active component, which has to exceed 60 %. The optimal grain size with 64 % of fraction of particle size -100 μm was obtained after 33 min of grinding of ≈3000 μm mm grain size MAP by using a ball mill (single-stage grinding). In two-stage process, by grinding the same initial MAP sample (≈3000 μm) in the vibro mill for 10 min, powder with the upper limit grain size of 300 μm and the mean grain diameter of 120 μm was obtained. This sample with a reduced size was further ground in the ceramic ball mill yielding 67.5 % of the fraction of particle size -100 μm after 19 min. The total time of the two-stage grinding process was 29 min. By analyzing the grinding time of MAP required to get the lowest required share of the fraction of particle size -100 μm that provides the effectiveness of formed PFE it can be concluded that 64 % of this fraction was obtained after 33 min of single-stage grinding, while only after 26 min in the two-stage process. Thus, the grinding time was reduced by 7 min indicating certain energy savings. Stability and hydrophobicity of the obtained PFE were achieved by coating with magnesium stearate (MgSt) at the content of 2 % in a ball mill for 15 min. The coating was confirmed by the standardized procedure for verification of PFE hydrophobic properties in contact with water drops. To obtained PFE had component mass ratios of MAP:AS:CC:QS:MgSt=55:20:18:5:2 (AS-ammonium sulfate; CC-calcium carbonate, QS-quartz sand) and was further characterized by chemical and granulometric analyses. The fire extinguishing efficiency of the PFE was tested in controlled conditions, whereby fires were initiated by burning solid materials and flammable liquids. In both cases, immediate elimination of flames was achieved, thus proving the efficiency of the PFE obtained in this work for practical applications.

Spironolactone is a potassium-sparing diuretic used as treatment for several diseases such as bronchopulmonary dysplasia, precocious puberty, hypertension or primary aldosteronism in child population. Because of the lack of paediatric formulations in the market, two types of solid oral formulation containing 2.5 and 10 mg of spironolactone were developed. During stability studies, excessive degradation was observed. As presented in this work, the degradation of spironolactone was linked to a drug excipient interaction between spironolactone and magnesium stearate via alkaline hydrolysis degradation pathway. In order to help the re-formulation with another lubricant, a complete drug excipient compatibility study was performed using thermal analysis techniques associated with chromatographic quantification of the drug after an isothermal stress testing. Spironolactone presents physicochemical incompatibilities with sodium benzoate, sodium stearyl fumarate, PEG 8000, PEG 20,000 and stearic acid. But no degradation was observed with PEG 20,000 and stearic acid indicating chemical compatibility. In total, talc, stearic acid and PEG 20,000 could be used for re-formulation of spironolactone paediatric drug. [ABSTRACT FROM AUTHOR]

Introduction: The appendage of “halal” to a product is not just a guarantee that the product is permitted for Muslims, but it has also become favorable lifestyle choice globally. However, the expansion of halal pharmaceutical market was hindered by lack of global halal standards for pharmaceutical ingredients and product integrity analytical methodology. Objective: This work aimed to explore the possibility of using Fourier-transform infrared (FTIR) spectroscopy and chemometrics to develop multivariate models to authenticate the “halal-ity” of pharmaceutical excipients with controversial halal status (e.g., magnesium stearate). Materials and Methods: The FTIR spectral fingerprints of the substance were used to build principal component analysis (PCA) models. The effects of different spectral pretreatment processes such as auto-scaling, baseline correction, standard normal variate (SNV), first, and second derivatives were evaluated. The optimization of the model performance was established to ensure the sensitivity, specificity, and accuracy of the predicted models. Results: Significant peaks corresponding to the properties of the compound were identified. For both bovine and plant-derived magnesium stearate, the peaks associated can be seen within the regions 2900 cm-1 (C–H), 2800 cm-1 (CH3), 1700 cm-1 (C=O), and 1000–1300 cm-1 (C–O). There was not much difference observed in the FTIR raw spectra of the samples from both sources. The quality and accuracy of the classification models by PCA and soft independent modeling classification analogy (SIMCA) have shown to improve using spectra optimized by first derivative followed by SNV smoothing. Conclusion: This rapid and cost-effective technique has the potential to be expanded as an authentication strategy for halal pharmaceuticals.

In the context of the present study, the thermal behavior of furosemide and the solid state excipients, sodium alginate, poly(ethylene oxide), poly(vinylpyrrolidone), lactose mono-hydrate and magnesium stearate, using Differential Scanning Calorimetry (DSC), was probed. It was found that the thermal behavior of these solid-state pharmaceutical excipients and furosemide correlates nicely with the literature relevant data. Regarding the furosemide-excipients mixtures, the DSC scans appear as a compilation of the thermal curves of each excipient. This suggests that the formulations containing these mixtures, may retain their stability over time. This information, which arises from the cooperativity of materials, their thermal stability and behavioris very helpful for the research and development of safe and effective pharmaceutical formulations. DSC experiments were also carried out with chimeric bilayers (called “liposomes”), composed of hydrogenated soy phosphatidylcholine (HSPC) and poly(n-butylacrylate)-b-poly(acrylic acid) block copolymer with 70 % content of poly(acrylic acid (PnBA-b-PAA 30/70) with the addition of furosemide at the molar ratio of 9:0.1:1.0 in the system HSPC:PnBA-b-PAA 30/70:furosemide. Chimeric liposomal systems were characterized as “fluid-like” by their DSC curves, which may be potentially translated as an easy way for release of furosemide from the advanced delivery system.

[Display omitted] Minitablets are prepared using multiple die openings and multi–tip punches for greater productivity. With multiple tips on the punch barrel, the overall compaction force to be applied is commonly estimated by multiplying the desired compaction force per tip by the number of punch tips. Few researchers have however examined this proportionality and the effects of the number of punch tips and punch face geometry on the critical quality attributes (CQAs) of high drug load minitablets. In this study, the minitablets prepared by multi–tip tools exhibited greater weight variation than those prepared by single–tip tools. Their compaction was accompanied by a longer dwell time that led to a higher minitablet tensile strength and consequently a longer disintegration time. The compaction forces required to achieve a consistent set of minitablet CQAs were not directly proportional to the number of punch tips used. In comparison, the effect of punch face geometry was negligible. Increasing concentration of magnesium stearate (as lubricant) from 0.75 to 1.25 %, w/w reduced weight variation, especially of minitablets prepared by the multi-tip tools. It also increased the disintegration time but had no significant effect on the tensile strength of the minitablets regardless of type of tools used. The adjustment of compaction speed was an effective compensatory method to mitigate the differences in dwell time and tensile strength between minitablets prepared by single–tip and multi–tip standard concave tools. A larger reduction in compaction speed of the single-tip tools was required at higher compaction pressures. [ABSTRACT FROM AUTHOR]

The powder flow plays an important role in the manufacture of dosage form such as direct compression tablets. The objective of this research was to investigate the individual and interaction effects of magnesium stearate (MgSt) (Merck Ltd., Germany) as lubricant and sodium starch glycolate (SSG) (Primojel®) as superdesintegrator on powder flowability. Powder formulations were prepared by mixing different concentration of MgSt (0.25% and 5%) and SSG (0.5% and 4%) with microcrystalline cellulose (MCC) (Vivapur®101) or spray-dried lactose (LAC) (Super Tab 21AN) as diluents. Eight powder formulations were prepared using as filler LAC and MCC, as superdesintegrator SSG and as lubricant MgSt in ratios as follows: P1 (LAC : 0.5% SSG : 0.25% MgSt); P2 (LAC : 4% SSG : 5% MgSt); P3 (LAC : 0.5% SSG : 5% MgSt); P4 (LAC : 4% SSG : 5% MgSt); P5 (MCC : 0.5% SSG : 0.25% MgSt); P6 (MCC : 4% SSG : 5% MgSt); P7 (MCC : 0.5% SSG : 5% MgSt); P8 (MCC : 4% SSG : 0.25% MgSt). The powder formulations were evaluated using indirect methods of flowability evaluation according to 9th European Pharmacopoeia: measurement of tapped and bulk density (Ph.Eur.9, 2.9.34) and angle of repose (Ph.Eur. 2.9.36). Also, compressibility index, Hausner’s ratio were calculated. A full factorial design with three factors at two levels and response surface methodology were applied to evaluate the influence of various concentrations of MgSt and SSG on powder flowability. The results indicate that flow properties improved with decrease of SSG content and with increase of MgSt content. Magnesium stearate in powder formulations with microcrystalline cellulose has a greater influence on the improvement of the flow properties than powder formulations with spray-dried lactose.

Local administration of growth-inhibiting substances such as paclitaxel or sirolimus could reduce the risk of restenosis. In the drug coated balloon (DCB) technology the coating and the applied dose seem to play a major role. The aim of the present preclinical studies was to investigate the efficacy and safety of a specific DCB with paclitaxel as active ingredient and magnesium stearate as excipient. Evaluation of the coating, drug release and transfer was done ex vivo and in vivo on peripheral arteries. A porcine coronary stent model was chosen to provoke intimal thickening. Conventional uncoated balloons were compared with paclitaxel urea and paclitaxel magnesium stearate coated balloons. QCA and histomorphometry was performed on treated vessels. Three areas of the heart were histologically examined for pathological changes. QCA and histomorphometry revealed no differences in baseline data between treatment groups. All DCB groups showed a significant reduction of angiographic and histologic parameters describing neointimal formation 4 weeks after treatment (e.g. mean angiographic late lumen loss all coated 0.31 ± 0.18 mm versus 0.91 ± 0.37 mm in the uncoated balloon group). There were no device-related animal deaths or clinical abnormalities. In spite of very slight-to-slight microscopic findings limited to small arterial vessels in downstream tissue there was no change in left ventricular ejection fraction or angiographic presentation of small side branches of treated arteries. Paclitaxel DCB using stearate as excipient show a high efficacy in reducing neointima formation after experimental coronary intervention. No evidence of myocardial damage resulting from distal embolization was found. • Paclitaxel/MgS coated balloons showed low drug split off and drug transfer comparable to paclitaxel/urea coated balloons. • All tested DCBs achieved reduced neointima formation (diameter stenosis, p = 0.001) and less luminal narrowing (late lumen loss, p = 0.001). • No microembolization despite of microembolization was detected in side branches of the treated vessels nor in myocardial tissue. [ABSTRACT FROM AUTHOR]

Palm fatty acid distillate (PFAD) was used as raw material to produce solid lubricant, or anti-adherent, for confectionery or pharmaceutical products. To improve the degree of saturation, the PFAD was hydrogenated by using two methods: gaseous hydrogenation (GH) and catalytic transfer hydrogenation (CTH) using ammonium formate to produce hydrogenated PFAD (HPFAD). The HPFAD was saponified with MgO to produce magnesium salts of hydrogenated PFAD (Mg-HPFAD). The objective of this research was to investigate the effect of hydrogen concentration and reaction temperature on the iodine value of HPFAD, and to investigate the characteristics of paracetamol tablets when using Mg-HPFAD as lubricant compared to commercial Mg-stearate. The HPFAD produced by CTH had a lower iodine value than the HPFAD produced by GH. The lowest iodine value was obtained after CTH using 3.6 M ammonium formate at 90ï,°C. Paracetamol tablets with Mg-PFAD or Mg-HPFAD lubricant showed higher dissolution of active compounds with similar friability, frictiability, and hardness compared to paracetamol tablets with Mg-stearate. [ABSTRACT FROM AUTHOR]

The research includes the formula and the testing of the nanoparticular nanoparticular nanoparticular mesylate tablet to improve biological availability of Eprosartan Mesylate. Nanoparticles were produced in the process of solvent evaporation using eprosartan, sodium dodecyl sulphate, ethanol and eudragit as polymer. The filled polymer F8 is subsequently compressed into the matrix tablet using magnesium stearate and ethyl cellulose. On nanoparticular matrix tablets, we evaluated micrometric characteristics, in-vitro testing, integrating performance, drug polymers compatibility, electrical scanning micro and in-vitro medications release. The standard type of dosage may lead to or below the medication and low adherence to the patient. These challenges are also reduced by the modern drug delivery system, which can provide edges such as dose frequency reductions, decreased dose size, precision targeting, enhanced porosity and oral bioavailability. [ABSTRACT FROM AUTHOR]

In this paper, the application of food-grade magnesium stearate microparticles as a stabilizer in the preparation of a novel biocompatible Pickering emulsions was reported. Water-in-oil (W/O) Pickering emulsions were successfully prepared in various solvents such as n-heptane, silicone oil, and food/cooking-grade olive oil, which are all acceptable solvents in the pharmaceutical, cosmetic, and food industries. To the best of our knowledge, there are no available reports on the application of safe and easily available Pickering emulsions prepared using stearate solid particles. It was found that the emulsions could be prepared using mild agitation methods such as shaking by hand, magnetic stirring, and vortex mixing. In contrast, vigorous agitations such as using a homogenizer prevented emulsion formation. It was realized that inorganic salts are a requisite for stable emulsion formations and CaCl2 produced the most stable emulsion. The size of the emulsion was dependent upon the concentration of the microparticle; therefore, its concentration was optimized in this study. The Sauter mean diameter of the emulsions was proportional to agitation speed, which is consistent with those of surfactant-free emulsion systems. We have shown that consistent preparation of emulsions is possible using the novel Pickering emulsion systems in comparison to the conventional surfactant-based emulsion systems. We demonstrated that safe and biocompatible Pickering emulsions can be prepared using easily available food-grade magnesium stearate microparticles without the need for artificial surfactants. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Magnesium stearate (MgSt) is a widely used pharmaceutical lubricant in tablet manufacturing. However, batch-to-batch variability in hydrate form and surface area can lead to inconsistency in tablet performance. In this work, several unique MgSt samples were studied: traditional monohydrate samples with high surface area, dihydrate forms with high and low surface area, and disordered forms with low and medium water content. The effects of solid-state form and particle properties on lubrication efficiency, tabletability and dissolution were studied for tablets in a model direct compression formulation. It was found that the monohydrate and dihydrate forms had good lubrication efficiency compared to the disordered form, while the disordered form had the best tabletability. The dissolution rate correlated with surface area, where slower dissolution rates corresponded with higher MgSt surface areas. The dihydrate sample with lower surface area had the best performance for this model formulation, in terms of lubrication efficiency, tabletability and dissolution. Overall, it is concluded that the choice of the most appropriate grade of MgSt for a particular formulation depends on a comprehensive evaluation of the impact of MgSt properties on lubrication efficiency, tabletability and dissolution. [ABSTRACT FROM AUTHOR]

Titanate nanotubes (TNTs) are promising vectors for drug delivery due to their unique physicochemical properties such as biocompatibility, mechanical strength, and chemical resistivity. However, considering their strong hydrophilicity, pristine TNTs exert very limited permeability through the intestinal cell layer. The aim of this study was to turn the surface characteristics and thus enhance the permeability of TNTs by functionalization. TNTs were functionalized with trichloro(octyl)silane (TCOS) and magnesium stearate (MgSt). Carbon content and surface free energy of the functionalized TNTs were detected to evaluate the effectiveness of functionalization, by using CHNS analytical and optical contact angle (OCA) measurements, respectively. Caco-2 cell line was applied to test the permeability and the cytotoxicity of the samples. Cytotoxicity was evaluated by using MTT assay. The results revealed that the surface characteristics of TNTs may be adjusted in a wider range with TCOS-TNT than with St, but the samples show higher toxicity. Silane functionalized TNTs may be safe up to 1 mg/ml, while St functionalized TNTs up to 2 mg/ml concentration. The preparation method of MgSt-TNT was also superior from the aspect of environmental safety. The permeability was suitable for samples with moderate hydrophobicity (aqueous contact angle 60-90°). [ABSTRACT FROM AUTHOR]

Introduction: The appendage of "halal" to a product is not just a guarantee that the product is permitted for Muslims, but it has also become favorable lifestyle choice globally. However, the expansion of halal pharmaceutical market was hindered by lack of global halal standards for pharmaceutical ingredients and product integrity analytical methodology. Objective: This work aimed to explore the possibility of using Fourier-transform infrared (FTIR) spectroscopy and chemometrics to develop multivariate models to authenticate the "halal-ity" of pharmaceutical excipients with controversial halal status (e.g., magnesium stearate). Materials and Methods: The FTIR spectral fingerprints of the substance were used to build principal component analysis (PCA) models. The effects of different spectral pretreatment processes such as auto-scaling, baseline correction, standard normal variate (SNV), first, and second derivatives were evaluated. The optimization of the model performance was established to ensure the sensitivity, specificity, and accuracy of the predicted models. Results: Significant peaks corresponding to the properties of the compound were identified. For both bovine and plant-derived magnesium stearate, the peaks associated can be seen within the regions 2900 cm-1 (C-H), 2800 cm-1 (CH3), 1700 cm-1 (C=O), and 1000-1300 cm-1 (C-O). There was not much difference observed in the FTIR raw spectra of the samples from both sources. The quality and accuracy of the classification models by PCA and soft independent modeling classification analogy (SIMCA) have shown to improve using spectra optimized by first derivative followed by SNV smoothing. Conclusion: This rapid and cost-effective technique has the potential to be expanded as an authentication strategy for halal pharmaceuticals. [ABSTRACT FROM AUTHOR]

Three different tableted coffee mix formulations were produced: coffee mix tablet, effervescent coffee mix tablet, and effervescent coffee mix tablet added with lubricant (2 w/w% magnesium stearate). The frictional effects during the ejection of the formed tablets out from the die, the mechanical strength and the disintegration of the tablets were investigated. The coffee mix tablet displayed the highest mechanical strength, followed by the effervescent coffee mix tablet. The effervescent coffee mix tablet containing the lubricant displayed the lowest mechanical strength. The addition of the effervescent agents to the coffee mix tablet increased the frictional effects during the ejection stage. This was decreased with the addition of the lubricant. The addition of the effervescent agents to the coffee mix tablet decreased the disintegration time but the addition of the lubricant increased the effervescent coffee mix tablet disintegration time. [ABSTRACT FROM AUTHOR]

Elucidating the impact of excipient variability on oral product performance in a biopharmaceutical perspective would be beneficial and allow excipient implementation on Quality by Design (QbD) approaches. The current study investigated the impact of varying viscosity of binders (hypromellose (HPMC)) and superdisintegrants (sodium starch glycolate (SSG)) and particle size distribution of lubricants (magnesium stearate (MgSt)) on the in vitro dissolution of a highly and a poorly soluble drug from immediate release formulations. Compendial (pharmacopoeia buffers) and biorelevant (media simulating the gastrointestinal fluids) media and the USP 2 and USP 4 apparatuses were used to assess the exerted excipient effects on drug dissolution. Real-time dissolution UV imaging provided mechanistic insights into disintegration and dissolution of the immediate release formulations. Varying the viscosity type of HPMC or SSG did not significantly affect drug dissolution irrespective of the compound used. Faster drug dissolution was observed when decreasing the particle size of MgSt for the highly soluble drug. The use of real-time dissolution UV Imaging revealed the influential role of excipient variability on tablet disintegration, as for the highly soluble drug, tablets containing high viscosity HPMC or low particle size MgSt disintegrated faster as compared to the control tablets while for the poorly soluble drug, slower tablet disintegration was observed when increasing the viscosity of the HPMC as compared to the control tablets. Changes in drug dissolution when varying excipients may be anticipated if the excipient change has previously affected drug solubility. The use of multivariate data analysis revealed the influential biopharmaceutical factors such as critical excipient types/properties, drug aqueous solubility, medium/hydrodynamic characteristics affecting the impact of excipient variability on in vitro drug dissolution. [ABSTRACT FROM AUTHOR]

Solid-state compatibility of API with excipients is essential step in the preformulation stage of early development of new finished dosage form. Thermal analysis and vibrational spectroscopy are complementary techniques that play a pivotal role to assess the solid-state compatibility of API with excipients. Their coupling and combination with multivariate analysis, provide valuable quantitative aspect to reveal the potential interactions. The impetus of this work was aimed to fully elucidate the solid-state compatibility of ibuprofen and magnesium stearate in binary mixtures comprising pharmaceutically acceptable amounts of magnesium stearate (0.25–5% w/w). Binary mixtures were analyzed before and after exposure at strictly controlled stress conditions (25 °C/60% relative humidity and 40 °C/75% relative humidity). Interaction between ibuprofen and magnesium stearate was unambiguously confirmed. The product of their interaction was synthetized separately, characterized by means of FTIR spectroscopy, DSC, TG/DTG and XRPD for the first time and identified as diibuprofen magnesium. The induced solid-state pseudopolymorphic transition of this product to diibuprofen magnesium tetrahydrate was also studied and discussed. [ABSTRACT FROM AUTHOR]

• Modify a scale-up lubrication model proposed by Kushner et al. via adding a lubricant cohesiveness term. • Consider the cohesiveness of Magnesium Stearate on lubrication process. • Utilize granular system instead of powder blend in present study. • Demonstrate superior prediction using our modified model. Kushner et al. proposed a scale-up model to describe the effect of lubrication on tablet tensile strength. In our study, a lubricant cohesiveness term, (1 + α/V), was added to the lubrication scale-up model reported by Kushner et al. to address the cohesiveness of magnesium stearate. The modified model proposed is as follows: TS SF=0.85 = TS SF=0.85,0 [β(1 + α/V)exp(−ϒ × 1.5 V1/3 × F headspace × r) + (1 − β)], where TS SF=0.85 is tablet tensile strength at solid fraction 0.85, V is blender size, F headspace is fraction of headspace, r is revolution number, TS SF=0.85,0 is theoretical initial tensile strength, α is the sensitivity constant of magnesium stearate powder cohesiveness, β is the sensitivity constant of the blend to lubrication, and γ is the lubrication rate constant. Using a high shear placebo granule, lubrication scale-up models were built using both equations, with and without the cohesiveness term, and tested by a 16-fold scale-up. The equation with the cohesiveness term demonstrated superior prediction of tablet tensile strength for scale-up within the selected granular system and the scale-up range studied in this work, indicating the usefulness of including magnesium stearate powder cohesiveness in building a scale-up predictive lubrication model using an active pharmaceutical ingredient (API) sparing approach with small quantity of materials. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Excipients are major components of oral solid dosage forms, and changes in their critical material attributes (excipient variability) and/or amount (excipient variation) in pharmaceutical formulations may present a challenge for product performance. Understanding the biopharmaceutical factors affecting excipient performance is recommended for the successful implementation of excipient variability on Quality by Design (QbD) approaches. The current study investigated the impact of magnesium stearate (MgSt) variability on the apparent solubility of drugs with a wide range of physicochemical properties (drug ionization, drug lipophilicity, drug aqueous solubility). Compendial and biorelevant media were used to assess the role of gastrointestinal (GI) conditions on the excipient effects on drug apparent solubility. The lipophilic nature of MgSt decreased the apparent solubility of most compounds. The reduction in drug apparent solubility was more pronounced for highly soluble and/or highly ionized drugs and in presence of more highly crystalline or smaller particle size MgSt. The use of multivariate data analysis revealed the critical physicochemical and biopharmaceutical factors and the complex nature of excipient variability on the reduction in drug apparent solubility. The construction of a roadmap combining drug, excipient and medium characteristics allowed the identification of the cases where the presence of excipient or excipient variability may present risks for oral drug performance. [ABSTRACT FROM AUTHOR]

Copyright of Farmacia is the property of Societatea de Stiinte Farmaceutice Romania and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the modern era, chewable tablets are preferred over conventional dosage forms by pediatric, geriatric and bedridden patients due to difficulty in swallowing, lesser amount of water for swallowing medications as well as unable to tolerate the bitter taste of certain drugs. Chewable tablets of Desloratadine (DS) were formulated by aqueous and non-aqueous granulation method using water paste and Isopropyl alcohol (IPA) as a wetting agents respectively. Desloratadine is used to treat the symptoms of allergy such as sneezing, watery eyes. In the recent research, we have formulated eight trials by various concentrations of excipients. For instance; lactose, talcum, magnesium stearate, blue color, flavor, aspartame, mannitol, avicel 101 and polyvenylpyrollidine (PVP). Pre-compression and post compression parameters (thickness, hardness, friability weight variation and drug content) of the formulations were evaluated. B3 was our optimum dosage form because its Hausner's ratio, compressibility index, bulk density, tap density, angle of repose have optimum values i.e. 1.01, 5.1%, 0.66(g/cc), 0.69(g/cc), 26.1° respectively and post-compression i.e. thickness, hardness, friability weight variation and drug content have values, 2.9mm, 3.9(kg/cm?), 0.6%, 99.5% respectively. Tablets prepared by wet granulation technique showed reasonable release profile i.e. 100% within the required time i.e. 2 hours. Moreover, organoleptic evaluation of all formulations were performed. [ABSTRACT FROM AUTHOR]

The objective of this research is to understand how the properties of magnesium stearate (MgSt) affect product performance in a quantitative manner using a multivariate modeling approach. In addition, we explored the feasibility of using NIR and Raman spectra as a surrogate measurement of physiochemical properties in prediction of performance in tablet direct compression. Partial least square models to predict performance attributes (PAs) from MgSt properties or spectra were developed and validated. The model input variables are MgSt physiochemical properties, spectra, key formulation and process parameters. Material physiochemical properties include fatty acid composition, loss on drying, densities, particle size distribution, specific surface area, and solid state properties. The key formulation and process parameters include MgSt concentration, filler type and compression force. The output variables are PAs including tablet ejection force, breaking force and disintegration time. It was found that the prediction of MgSt performance from its properties greatly depends on filler type and PAs of interest. NIR spectra successfully predicted lubricant performance in lactose tablet; however, predictions from Raman spectra were not acceptable. In the cases that the contributing physiochemical properties in performance prediction are sufficiently captured in the spectra, the spectra can be used as an alternative tool to predict excipient performance. [ABSTRACT FROM AUTHOR]

[Display omitted] The majority of tablets manufactured contain lubricants to reduce friction during ejection. However, especially for plastically deforming materials, e.g., microcrystalline cellulose (MCC), the internal addition of lubricants is known to reduce tablet tensile strength. This reduction is caused by the surface coverage by lubricant particles, the extent of which depends on both process and formulation parameters. Previously published models to predict the lubrication effect on mechanical strength do not account for changes in the excipient particle size. In this study, the impact of both lubricant concentration and mixing time on the tensile strength of tablets consisting of three different grades of MCC and four grades of magnesium stearate (MgSt) was evaluated. By taking into account the particle size of the applied excipients, a unifying relationship between the theoretically estimated surface coverage and compactibility reduction was identified. Evaluating the dispersion kinetics of MgSt as a function of time reveals a substantial impact of the initial surface coverage on the dispersion rate, while the minimal tensile strength was found to be comparable for the majority of formulations. In summary, the presented work extends the knowledge of lubricant dispersion and facilitates the reduction of necessary experiments during the development of new tablet formulations. [ABSTRACT FROM AUTHOR]

[Display omitted] External lubrication of tooling with magnesium stearate (MgSt) is a common strategy to eliminate punch sticking when compressing powders with a high sticking propensity, such as many pure active pharmaceutical ingredients (APIs). We found that it actually led to aggravated punch sticking at low compaction pressures. This counterintuitive phenomenon was explained based on interplay of forces among the punch tip, MgSt, and API. The explanation is supported by the observed effects of pressure and mechanical properties of APIs on this phenomenon. [ABSTRACT FROM AUTHOR]

Glidants and lubricants are often used to modify interparticle friction and adhesion in order to improve powder characteristics, such as flowability and compactability. Magnesium stearate (MgSt) powder is widely used as a lubricant. Shear straining causes MgSt particles to break, delaminate, and adhere to the surfaces of the host particles. In this work, a comparison is made of the effect of three mixer types on the lubricating role of MgSt particles. The flow behaviour of α-lactose monohydrate, coated with MgSt at different mass percentages of 0.2, 0.5, 1, and 5 is characterised. The mixing and coating process is carried out by dry blending using Turbula, ProCepT, and Mechanofusion. Measures have been taken to operate under equivalent mixing conditions, as reported in the literature. The flow resistance of the coated samples is measured using the FT4 rheometer. The results indicate that the flow characteristics of the processed powders are remarkably similar in the cases of samples treated by Turbula and Mechanofusion, despite extreme conditions of shear strain rate. The least flow resistance of samples is observed in the case of samples treated by the ProCepT mixer. High-velocity collisions of particles round off the sharp corners and edges, making them less resistant to flow. The optimal percentage of magnesium stearate is found to be approximately 1% by weight for all mixer types, as the addition of higher amounts of lubricant does not further improve the flowability of the material.

Agglomerate formulations for dry powder inhalation (DPI) formed with fine particles are versatile means for the highly efficient delivery of budesonide. However, uncontrolled agglomeration induces high deposition in the upper airway, causing local side effects due to high mechanical strength, worse deagglomeration, and poor fine-particle delivery. In the present study, fine lactose was mechanically dry-coated prior to particle agglomeration, and the agglomerates were then spheroidized via ultrasonic vibration to improve their aerosol performance. The results showed that the agglomerate produced with the surface-enriched hydrophobic magnesium stearate and ultrasonic vibration demonstrated improved aerosolization properties, benefiting from their lower mechanical strength, less interactive cohesive force, and improved fine powder dispersion behavior. After dispersion utilizing a Turbuhaler ® with a pharmaceutical cascade impactor test, a fine particle fraction (FPF) of 71.1 ± 1.3% and an artificial throat deposition of 19.3 ± 0.4% were achieved, suggesting the potential to improve the therapeutic outcomes of budesonide with less localized infections of the mouth and pharynx.

In the case of capsule-based dry powder inhalation systems (DPIs), the selection of the appropriate capsule is important. The use of gelatin, gelatin-PEG, and HPMC capsules has become widespread in marketed capsule-based DPIs. We aimed to perform a stability test according to the ICH guideline in the above-mentioned three capsule types. The results of the novel combined formulated microcomposite were more favorable than those of the carrier-free formulation for all capsule types. The use of HPMC capsules results in the greatest stability and thus the best in vitro aerodynamic results for both DPI powders after six months. This can be explained by the fact that the residual solvent content (RSC) of the capsules differs. Under the applied conditions the RSC of the HPMC capsule decreased the least and remained within the optimal range, thus becoming less fragmented, which was reflected in the RSC, structure and morphology of the particles, as well as in the in vitro aerodynamic results (there was a difference of approximately 10% in the lung deposition results). During pharmaceutical dosage form developments, emphasis should be placed in the case of DPIs on determining which capsule type will be used for specific formulations.

Objective: The aim was to study the stability of dry powder inhaler (DPI) formulations containing antibiotic with different preparation ways – carrier-based, carrier-free, and novel combined formulation – and thereby to compare their physicochemical and in vitro–in silico aerodynamical properties before and after storage. Presenting a novel combined technology in the field of DPI formulation including the carrier-based and carrier-free methods, it is the most important reason to introduce this stable formulation for the further development of DPIs. Methods: The structure, the residual solvent content, the interparticle interactions, the particle size distribution and the morphology of the samples were studied. The aerodynamic values were determined based on the cascade impactor in vitro lung model. We tested the in silico behavior of the novel combined formulated samples before and during storage. Results: The physical measurements showed that the novel combined formulated sample was the most favorable. It was found that thanks to the formulation technique and the use of magnesium stearate (MgSt) has a beneficial effect on the stability compared with the carrier-based formulation without MgSt and carrier-free formulations. The results of in vitro and in silico lung models were consistent with the physical results, so the highest deposition was found for the novel combined formulated sample during the storage. Conclusions: It can be established that after the storage a novel combined formulated DPI contained amorphous drug to have around 2.5 μm mass median aerodynamic diameter and nearly 50% fine particle fraction predicted high lung deposition in silico also. [ABSTRACT FROM AUTHOR]

Abstract The causes of atypical nitrogen adsorption isotherm features of commercial magnesium stearate grades have been investigated through a combination of alternative adsorbates and variation of analytical conditions. Atypical features have previously been identified as having poor linearity of adsorption isotherms at relative pressures applied to the calculation of BET surface area and low pressure hysteresis between adsorption and desorption branches. These features are most pronounced for di-hydrated MgSt and are absent for the anhydrous form: the presence of hydrated water causing atypical features. The possible interaction between hydrated water molecules and nitrogen via the nitrogen quadrupole is investigated through application of non-polar adsorbates; argon and krypton. Low pressure hysteresis is investigated through alteration of equilibration conditions and through truncating adsorption isotherms to successively lower maximum relative pressures before commencing desorption. It is found that atypical gas sorption isotherms are not limited to nitrogen. The effects of these conditions on adsorption and desorption volumes are discussed and a model for the origin of atypical isotherm features is presented. The difference in gas sorption behaviour of anhydrous, mono-hydrated and di-hydrated magnesium stearate is discussed and ultimately the consequences on the calculation of BET surface area is considered. Graphical abstract Unlabelled Image Highlights • Study of atypical adsorption isotherms of Mg stearate in varying hydration states. • N 2 , Kr and Ar used to investigate BET surface area and isotherm hysteresis. • Possible causes of atypical BET surface area and isotherm data are discussed. • Structural swelling of magnesium stearate and adsorptive entrapment is shown. • BET surface area shown to be over-estimated particularly with the di-hydrate. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Appropriate lubrication is important in tablet manufacturing as it lowers punch sticking propensity and protects tooling by reducing friction between die wall and tablet during tablet manufacturing. Most commercial lubricants negatively impact tabletability and dissolution. A delicate balance is usually attained by trial and error to identify the optimal level of lubricant in a tablet formulation. In this work, we have evaluated the effectiveness of sodium lauryl sulfate (SLS), a surfactant, as a tableting lubricant. If adequate lubrication efficiency is achieved, the use of SLS may be suitable to mitigate problems associated with hydrophobic lubricants. Results show that SLS, when applied in the proper amount to typical pharmaceutical powder mixtures, achieved lubrication efficiency comparable to a grade of magnesium stearate (MgSt) without deteriorating tabletability. Moreover, SLS-containing tablets of celecoxib also exhibited improved in vitro dissolution compared to MgSt-containing tablets. The enhancement in dissolution properties was attributed to the improved wetting by the dissolution medium due to the presence of SLS. [ABSTRACT FROM AUTHOR]