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AbstractMethiocarb is a carbamate pesticide and is widely used due to its short lifetime but is a health concern due to its toxicity. To address this challenge, a novel nano-sorbent (zinc aluminate hybrid doped onto a magnetic activated carbon cloth (magnetic ACC@ZnAl2O4)) was synthesized. The characterization of the composite was done using FTIR spectroscopy, SEM, XRD, and EDX. The synthesized composite was then employed for the efficient extraction of methiocarb from food samples. Under the optimum conditions of (pH: 7.0, vortex time: 0.5 min, adsorbent dose: 5 mg, initial volume of sample: 50 mL, volume of eluent: 1.0 mL), quantitative recovery values of methiocarb in food samples were obtained (80–114%). This method impresses with its exceptional sensitivity, achieving incredibly low detection (LOD: 20 µg L−1) and quantification (LOQ: 67 µg L−1) limits for methiocarb. Its efficiency is equally impressive, with high values of preconcentration factor (PF: 50) and enhancement factor (EF: 49.4), ensuring accurate and reliable analysis with a low value of relative standard deviation (RSD: 4.8%). The method’s impressive selectivity, evident in its minimal interference from other pesticides, paves the way for reliable methiocarb analysis in food samples. [ABSTRACT FROM AUTHOR]

Photocatalysis is a promising technology for the degradation of recalcitrant organic pollutants in water. In this study, superparamagnetic zinc ferrite nanoparticles (ZnFe2O4) were synthesized and characterized using scanning electron microscopy, X-ray diffraction, energy dispersive X-ray and Fourier transform infrared spectroscopy. The synthesized nanoparticles (NPs) of ZnFe2O4 were observed to have a photosensitive nature and showed characteristic visible-light-induced activation that was used for the photocatalytic degradation of a textile dye, Remazol brilliant violet 5R (RBV-5R). The effect of different operational parameters such as pH, H2O2, catalyst dosage, concentration of RBV-5R and the reusability of ZnFe2O4 as well as scavengers were investigated under visible irradiation. The almost complete degradation (99.9%) of RBV-5R was observed at pH 10, 0.1 g of ZnFe2O4 and 6 mM of H2O2 in 30 min. The photocatalytic degradation of RBV-5R followed pseudo-first-order kinetics. The mineralization was calculated from total organic carbon (TOC) that was represented by 82% TOC removal in 30 min. The results revealed that visible-light-induced ZnFe2O4 photocatalysis may be a promising technology for the elimination of toxic organic dyes, such as RBV-5R, from water resources. [ABSTRACT FROM AUTHOR]

Heavy metal-based pollutants are one of the most alarming health hazards causing multiple diseases including cancer, hepatotoxicity, brain hemorrhage, kidney and heart failures, etc. In this study, we report an ecofriendly, low cost, and simple synthesis of silver nanoparticles (AgNPs) mediated by Nannorrhops ritchiana leaf-based biomolecular extract as a key biosensor for the mercury(II) heavy metal. The formation of AgNPs was confirmed by using different characterization techniques including UV–visible spectroscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The synthesized AgNPs are yellowish-brown and exhibit the surface plasmon resonance around 435 nm. The various functional groups responsible for reduction of Ag+ to Ag0 and capping agents present in the leaf extract were confirmed by infrared spectroscopy. Energy-dispersive X-ray and scanning electron microscopic analysis were used to confirm the presence of silver and surface morphology of the nanoparticles, respectively. X-ray diffraction data suggested crystalline nature of the prepared nanoparticles. The AgNPs were successfully applied as a sensitive and selective platform for sensing of mercury(II) ions. Various parameters including nanoparticles loading, concentration of Hg+2, pH, and reaction time were optimized. The platform demonstrates a low limit of detection (4.8 × 10–7 M) and limit of quantification (4.8 × 10–7 M) with an R2 value of 0.999. The SS-DNA interaction with the AgNPs, studied by UV–Vis spectroscopy revealed intercalative mode of binding with a binding constant of 1.04 × 104 units. Importantly, this AgNPs platform also demonstrated good antibacterial efficacy against Proteus mirabilis, Shigella flexneria, Escherichia coli, and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

The focus of the present work was to develop co-amorphous dispersion (CAD) formulations of tacrolimus (TAC) using sucrose acetate isobutyrate as a carrier, evaluate by in vitro and in vivo methods and compare its performance with hydroxypropyl methylcellulose (HPMC) based amorphous solid dispersion (ASD) formulation. CAD and ASD formulations were prepared by solvent evaporation method followed by characterization by Fourier transformed infrared spectroscopy, X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), dissolution, stability, and pharmacokinetics. XRPD and DSC indicated amorphous phase transformation of the drug in the CAD and ASD formulations, and dissolved more than 85% of the drug in 90 min. No drug crystallization was observed in the thermogram and diffractogram of the formulations after storage at 25 °C/60% RH and 40 °C/75% RH. No significant change in the dissolution profile was observed after and before storage. SAIB-based CAD and HPMC-based ASD formulations were bioequivalent as they met 90% confidence of 90–11.1% for Cmax and AUC. The CAD and ASD formulations exhibited Cmax and AUC 1.7–1.8 and 1.5–1.8 folds of tablet formulations containing the drug's crystalline phase. In conclusion, the stability, dissolution, and pharmacokinetic performance of SAIB-based CAD and HPMC-based ASD formulations were similar, and thus clinical performance would be similar. [ABSTRACT FROM AUTHOR]

In the present study synthesis of magnetic nanoparticle (MNPs), impregnated walnut shell powder (MNPs-WSP) were carried out using the co-precipitation method and used for the solid-phase extraction of Cd(II) from environmental water samples. Impregnated walnut shell powder (MNPs- WSP) was characterized by using Fourier transform infrared spectroscopy for functional group, scanning electron microscopy for surface morphology, energy dispersive X-ray analysis for elemental analysis, X-ray diffraction for crystallinity and SAA for surface area, pore volume and pore size. For quantitative percent recovery various analytical parameters like solution pH, sample volume, vertex time, temperature and initial metal ion concentration were optimized. Analytical parameters like limit of detection, limit of quantification and enhancement factor were also calculated under optimized experimental conditions. The kinetic data shows that the adsorption of Cd(II) on MNPs and MNPs-WSP follows pseudo-second-order kinetics. Values of ΔH°, ΔS° and ΔG° show that these adsorption processes are endothermic and feasible in nature. For equilibrium studies different isotherms like Langmuir and Freundlich, adsorption isotherms were applied. The method was successfully applied to environmental water samples like tap water, underground water, dam water and wastewater with satisfied recovery results. [ABSTRACT FROM AUTHOR]

The development of biocompatible, cost effective and more efficient materials to control or inhibit the growth of microorganisms in necessary to fight against resistant microbes. Here, we demonstrate the synthesis of nickel oxide-incorporated polyaniline/polyvinyl alcohol (PANI/PVA/NiOx) composite material by single-step polymerization and its application as antibacterial agent. The composite films were characterized using UV-visible spectroscopy (UV-Vis), Thermogravimetric analysis (TGA), Fourier Transform Infrared spectroscopy (FTIR), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). UV-Vis spectra revealed the enhancement in absorption properties of PANI/PVA/NiOx with optimum 5% incorporation of NiOx. TGA results indicated slightly enhanced thermal stability of the PANI/PVA/NiOx composite film as compared to PANI/PVA. FTIR spectra for composites revealed the existence of NiOx in polymers. However the crystallinity of PANI/PVA was not much affected. The antibacterial activity of the prepared composites was examined against four different gram negative bacteria, Salmonella, Shigella, Pseudomonas and Escherichia coli (E. coli). The composite exhibited excellent antibacterial activity against E. coli, Salmonella and Shigella while pseudomonas showed some resistance. Based on the results, PANI/PVA/ NiOx (5%) composite showed the highest activity against the tested bacterial strains, thus showing its potential to be used as an effective antibacterial agent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel material Ti 3 AlC 2 max phase graphene oxide GO nanocomposite has been synthesized. • Solid phase extrication method based Ti 3 AlC 2 max phase GO nanocomposite has been develop for palladium. • All the extrication efficiency effecting parameters of the adsorbent has been optimized. • The method was applied to medical appliances samples. Palladium is an important metal as it has a wide range of applications in different fields but can cause cancer in human beings. Therefore, precise quantification of palladium is important. For this purpose, new material Ti 3 AlC 2 max phase having unique properties like high stability, thermal conductivity and environmental friendly has been synthesized. To increase its surface area of Ti 3 AlC 2 max phase, graphene oxide (GO) has been incorporated to form Ti 3 AlC 2 max phase GO nanocomposite. Ti 3 AlC 2 max phase GO nanocomposite was used as solid phase extracting material for microextraction and preconcentration of Pd(II) in environmental samples and medical appliances. Characterization of the adsorbent was achieved by using fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) and surface area analyzer (SAA). All the parameters that influence the extraction efficiency of the adsorbent like solution pH, amount of adsorbent, volume of sample, vortex time, desorption condition and interferences effect were determined and optimized. The limit of detection (0.327 µg/L) and limit of quantification (1.09 µg/L) show that the method is highly sensitive. The relative standard deviation was calculated as 5.48 % for five repeated measurements, which shows that the developed method is reproducible. The method is highly efficient with large values of preconcentration factor (20) and enhancement factors (20). The method was validated by applying the method to real water samples, soil samples and medical appliances with satisfied recovery results (94–106 %). [ABSTRACT FROM AUTHOR]

• Fe 3 O 4 -Ti 3 AlC 2 Max Phase has been synthesized used magnetic solid phase extraction of trace metals. • All the parameters that effect extraction efficiency were determined and optimized. • Certified reference materials were used for method validation. • The method was applied to water and food samples. In this work, we report the preparation of Fe 3 O 4 -Ti 3 AlC 2 max phase impregnated with 2-(5-Bromo-2-pyridylazo-5-(diethylamino) phenol) and its implementation for the extraction of cadmium, lead and cobalt from water and food samples. Blended Fe 3 O 4 -Ti 3 AlC 2 max phase impregnated with 2-(5-Bromo-2-pyridylazo-5-(diethylamino) phenol) was characterized using different instrumental techniques like scanning electron microscopy (SEM), surface area analyser (SAA), energy dispersive X-rays (EDX), Fourier transform infrared spectroscopy (FT-IR) and X-rays diffraction (XRD) for surface morphology, surface region, elemental composition, functional group and crystallinity, respectively. Factors that impact the % recoveries of analyte i.e pH, sample volume, vortex time, desorption condition and matrix impact were optimized. Analytical parameters like limit of detection (LOD) (Cd: 0.093 µg/L, Pb: 0.297 µg/L, Co: 0.223 µg/L), limit of quantifications (LOQ) (Cd: 0.310 µg/L, Pb: 0.992 µg/L, Co: 0.744 µg/L) preconcentration factors (PF) (Cd = Pb = Co: 40), enrichment factors (EF) (Cd: 39.8, Pb: 39, Co: 40) and relative standard deviation (RSD) (Cd: 3.8, Pb: 5.98, Co: 4.0) were determined under optimized trial conditions. The proposed strategy was tested using certified reference materials like TMDA-64.3 natural water and tobacco leaves (INCT-OBTL-5) for trace metal analysis. The developed strategy was also applied effectively to natural water samples and food samples using the standard addition method with good recovery results. [ABSTRACT FROM AUTHOR]

Abstract: The focus of present research was to understand and control the variability of solid dispersion (SD) formulation of non-ribosomal peptide antibiotic, vancomycin (VCM). Hunter screening design was constructed using seven independent variables namely melting temperature (X 1), congealing temperature (X 2), mixing time (X 3), type of capsule shell (X 4), filling method (X 5), molecular weight of polyethylene glycol (PEG, X 6) and surfactant type (X 7), and responses measured were cumulative percentage of VCM released in 45min (Y 1) and potency (Y 2). The SD formulations were prepared by melt-fusion method, and tested for dissolution, potency, and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and near infrared chemical imaging (NIR-CI). Statistically significant (p <0.05) effect of congealing temperature (X 2), type of capsule shell (X 4), filling method (X 5), molecular weight of PEG (X 6) was revealed on Y 1, and R 2 of 0.992 was obtained between experimental and predicted value. None of the factors have statistically significant (p >0.05) influence on Y 2. SEM, DSC and PXRD indicated crystalline nature of SD formulations. Homogeneity of SD formulations was shown by NIR-CI images. In summary, the quality of VCM SD formulations could be assured by controlling the critical factors during manufacturing. [Copyright &y& Elsevier]

There is an urgent need for the analysis of melamine in the global pharmaceutical supply chain to detect economically motivated adulteration or unintentional contamination using a simple, nondestructive analytical technique that confirms the extent of adulteration in a shorter time period. In this work, different analytical techniques (thermal analysis, X-ray diffraction, Fourier transform infrared ( FT- IR), FT- Raman, and near-infrared ( NIR) spectroscopy) were evaluated for their ability to detect a range of melamine levels in gelatin. While FT- IR and FT-Raman provided qualitative assessment of melamine contamination or adulteration, powder X-ray diffraction and NIR were able to detect and quantify the presence of melamine at levels as low as 1.0% w/w. Multivariate analysis of the NIR data yielded the most accurate model when three principal components were used. Data were pretreated using standard normal variate transformation to remove multiplicative interferences of scatter and particle size. The model had a root-mean-square error of calibration of 2.4 ( R2 = 0.99) and root-mean square error of prediction of 2.5 ( R2 = 0.96). The value of the paired t test for actual and predicted samples (1%-50% w/w) was 0.448 ( p < 0.05), further indicating the robustness of the model. Published 2013. This article is a U.S. Government work and is in the public domain in the USA 103:539-544, 2014 [ABSTRACT FROM AUTHOR]

The objective of the current study was to evaluate the performance of Raman and near-infrared (NIR) techniques combined with chemometrics in characterizing the critical quality attributes of brompheniramine (BP)-tannate complexes. Seven complexes were prepared and evaluated for chemical interactions, solubilities, dissolutions, and spatial distributions by NIR chemical imaging (CI). Principal component analysis (PCA) was applied before either partial least squares regression (PLSR) or principal component regression (PCR) models were developed. Complexation was confirmed by Fourier transform IR analysis to yield complexes of lower drug solubilities and sustained-release characteristics in alkaline media. PCA results showed better discrimination ability by NIR than by Raman spectroscopy. Compared with PCR, the PLSR predictions errors, calculated from the Raman and NIR data with second-derivative pretreatment, showed lesser values of 2.68, 0.37, 1.79, and 5.60 and 0.58, 0.25, 0.93, and 0.58 for complex solubilities in acidic and alkaline media and percentages dissolved after 1 and 20 h, respectively. In addition, good correlation (>0.95) was obtained for predicting the drug concentration using PLSR score images explaining the validity of the NIR-CI model for spatial quantitation of BP within its tannate complexes. In conclusion, the chemometric analysis of NIR and/or Raman spectra represented an innovative approach to determine the tannate complexation variability. © 2011 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 101:1450-1461, 2012 [ABSTRACT FROM AUTHOR]

Abstract Carbamazepine (CBZ) exists in anhydrous and dihydrate forms. These forms differ in their solubility, dissolution rate, and subsequently in their oral bioavailability. The objective of this study is to develop multivariate chemometric models for estimation of the low level of carbamazepine dihydrate (CBZ-DH) in the CBZ formulations containing excipients of the commercial formulation. The selected excipients were mixed in proportions to make sample matrices ranging from 0% to 50% CBZ-DH. Fourier transform infrared (FTIR), near infrared (NIR), and hyperspectral imaging data were mathematically pretreated before the development of partial least square and principal component analysis regression models. The developed partial least squares regression and principal component analysis models demonstrated predictability of CBZ and CBZ-DH by multiple scattering correction and standard normal variate processing methods. Among the spectroscopic techniques used the model performance parameters such as root-mean-square error, standard error, and bias were found to be low for NIR compared to FTIR. The treated data have shown better model fitting than without treatment, which was demonstrated by correlation coefficient of 0.9778, 0.9824, and 0.9852 for FTIR, NIR, and hyperspectral imaging, respectively. Furthermore, the predicted values were found to be very close to the selected low level of independent samples having 5% CBZ-DH in tablet formulation. [ABSTRACT FROM AUTHOR]

The objective of the present research was to study the feasibility of using near-infrared ( NIR) and Fourier transform infrared ( FTIR)-based chemometric models in quantifying crystalline and amorphous tacrolimus from its sustained-release amorphous solid dispersion ( ASD). ASD contained ethyl cellulose, hydroxypropyl methyl cellulose, and lactose monohydrate as carriers, and amorphous form of tacrolimus in it was confirmed by X-ray powder diffraction. Crystalline physical mixture was mixed with ASD in various proportions to prepare sample matrices containing 0%-100% amorphous/crystalline tacrolimus. NIR and FTIR of the samples were recorded, and data were mathematically pretreated using multiple scattering correction, standard normal variate, or Savitzky- Golay before multivariate analysis, partial-least-square regression ( PLSR), and principle component regression ( PCR). The PLSR models were more accurate than PCR for NIR and FTIR data as indicated by low value of root-mean-squared error of prediction, standard error of prediction and bias, and high value of R2. Additionally, NIR data-based models were more accurate and precise than FTIR data models. In conclusion, NIR chemometric models provide simple and fast method to quantitate crystalline tacrolimus in the ASD formulation. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:2376-2385, 2014 [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the performance of the chemometric model to predict the proportion of the recrystallized polymorphs of nimodipine from the cosolvent formulations. Ranging from 100% to 0% (w/w) of polymorph I, the two polymorphs mixtures were prepared and characterized spectroscopically using Fourier transformed infrared spectroscopy ( FTIR), near-infrared spectroscopy ( NIR), and Raman spectroscopy. Instrumental responses were treated to construct multivariate calibration model using principal component regression ( PCR) and partial least square regression approaches. Treated data showed better model fitting than without treatment, which demonstrated higher correlation coefficient ( R2) and lower root mean square of standard error ( RMSE) and standard error ( SE). Multiple scattering correction and standard normal variate exhibited higher R2 and lower RMSE and SE values than second derivative. Goodness of fit for FTIR and NIR ( R2 ∼ 0.99) data was better than Raman ( R2 ∼ 0.95). Furthermore, the models were applied on the recrystallized polymorphs obtained by storing nimodipine-cosolvent formulations at selected stability conditions. The relative composition of the polymorphs differed with storage conditions. NIR-chemical imaging on recrystallized sample of nimodipine at 15°C qualitatively corroborated the model-based prediction of the two polymorphs. Therefore, these studies strongly suggest the importance of the potential utility of the chemometric model in predicting nimodipine polymorphs. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:4024-4035, 2013 [ABSTRACT FROM AUTHOR]

Abstract: The focus of present investigation was to evaluate the tannic acid (TA) complexes of cholorpheniramine maleate (CPM) and characterize it by a variety of physicochemical, dissolution, and electronic tongue methods. The complexes were prepared in various molar ratios by solvent evaporation method. They were characterized by spectroscopic, thermal, powder X-ray, electronic tongue, solubility and dissolution methods. FTIR (infrared red) spectra showed complex formation between the TA and CPM. Complex formation has significantly lowered the drug solubility and sustained its release for more than 24h in phosphate buffer pH 6.8. On the contrary, the release was much faster in the presence of Avicel PH 113 in the same molar ratio complex. The complex formulation has suppressed the bitter taste of CPM as indicated by Euclidean distance in electronic tongue evaluation. NIR-CI (near infrared chemical imaging) showed lower skew value that indicated the homogenous distribution of formulation components. The chemometric models were also developed using the NIR data. The model based on second derivative data was better in predicting the TA and CPM loading as indicated by higher values of R, R 2 and lower values of root mean square error and standard errors. Furthermore, it has a better accuracy and less biased in comparison to other models. In conclusion, the CPM tannate has a sustained release behavior and excipients play a major role in modifying its release. Additionally, the complexes with varying molar ratio of tannate to CPM have differential taste masking abilities than that of the pure drug. [Copyright &y& Elsevier]

Spectral differences among multiple manufacturers/lots of sevelamer HCl were observed by Fourier transform infrared spectroscopy, and further characterization was performed to identify the cause for these differences. The drug substance is a polymer that possesses a large molecular weight, is amorphous, and is practically insoluble in both water and organic solvents. Thus, solid-state characterization methods (spectroscopic and thermal) were required to identify and characterize differences among the samples to assess possible differences in product quality. 13C cross-polarization-magic-angle-spinning nuclear magnetic resonance spectroscopy of sevelamer HCl substances demonstrated the presence of a carbonyl-containing species, which was attributed to a carbonate impurity among samples. Stability studies demonstrated that this carbonate impurity formed spontaneously upon exposure of the drug substance to atmospheric water vapor and carbon dioxide, even under ambient conditions. Mechanistically, this behavior likely arises from the large number of primary and secondary amine groups, the hygroscopicity of the HCl salt, and a high degree of molecular mobility due to the amorphous nature of the drug substance. © 2012 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 101:2681-2685, 2012 [ABSTRACT FROM AUTHOR]

Abstract: The aim of this investigation was to evaluate the complexation potential of brompheniramine maleate (BPM) and tannic acid (TA) for sustained release and taste masking effects. The complexes (1:1–1:7 TA to BPM ratio) were prepared by the solvent evaporation method using methanol, phosphate buffer pH 6.8 or 0.1N HCl as common solvents. The complexes were characterized microscopically by scanning electron microscopy (SEM), chemically by Fourier transform infrared (FTIR) and solid-state NMR (SSNMR), thermally by differential scanning calorimetry (DSC), for crystallinity by powder X-ray powder diffraction (PXRD), for organoleptic evaluation by electronic tongue (e-tongue), and for solubility in 0.1N HCl and phosphate buffer pH 6.8. The dissolution studies were carried out using the USP II method at 50rpm in 500ml of dissolution media (0.1N HCl or phosphate buffer pH 6.8). SEM images revealed that the morphology of complexes were completely different from the individual components, and all complexes had the same morphological characteristics, irrespective of the solvent used for their preparation, pH or ratio of BPM and TA. The FTIR spectra showed the presence of chemical interactions between the TA and BPM. DSC, PXRD and SSNMR indicated that the drug lost its crystalline nature by formation of the complex. Complexation has significantly reduced the solubility of BPM and sustained the drug release up to 24h in phosphate buffer pH 6.8 media. The bitter taste of the BPM was completely masked which was indicated by Euclidean distance values which was far from the drug but near to its placebo in the complexes in all ratios studied. The taste masked complexes can be potentially developed as suitable dosage forms for pediatric use. In summary, complexation of BPM and TA effectively sustained the dissolution and masked the bitter taste of drug for the development of suitable dosage forms for pediatric use. [Copyright &y& Elsevier]

Abstract: The aim of this investigation was to screen and understand the product variability due to important factors affecting the characteristics CyA-PLGA nanoparticles prepared by O/W emulsification-solvent evaporation method. Independent variables studied were cyclosporine A (CyA) (X 1), PLGA (X 2), and emulsifier concentration namely SLS (X 3), stirring rate (X 4), type of organic solvent employed (chloroform or dichloromethane, X 5) and organic to aqueous phase ratio (X 6). The nanoparticles properties considered were encapsulation efficiency (Y 1), mean particle size (Y 2), zeta potential (Y 3), burst effect (Y 4) and dissolution efficiency (Y 5). The statistical analysis of the results allowed determining the most influent factors. The nanoparticles were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray powder diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The factors combination showed variability of entrapment efficiency (Y 1), mean particle size (Y 2) and zeta potential (Y 3) from 10.17% to 93.01%, 41.60 to 372.80nm and 29.60 to 34.90mV, respectively. Initially, nanoparticles showed burst effect followed by sustained release during the 7-day in vitro release study period. The dissolution efficiency (Y 5) varied from 52.67% to 84.11%. The nanoparticles revealed Higuchi release pattern and release occurred by coupling of diffusion and erosion. In conclusion, this study revealed the potential of QbD in understanding the effect of formulation and process variables on the characteristics on CyA-PLGA nanoparticles. [Copyright &y& Elsevier]

Rifaximin (RFX) exhibit polymorphism and commercial formulation contains the α form. The polymorphic transformation of the RFX in the drug product have significant effect on the clinical outcome. The focus of present work was to understand effect of formulation component and manufacturing method, and exposure to stability condition on polymorphic stability and dissolution of RFX tablets. The RFX tablets containing 2.5, 5 and 10% glyceryl palmitostearate (GPS) were manufactured by direct-compression and wet-granulation followed by compression. Ethanol was used as a granulating solvent. The tablets were packed in pharmacy vials and exposed to 40 °C/75% RH for four weeks. The tablets were characterized for polymorphic form by X-ray powder diffraction (XRPD) and Fourier infrared spectroscopy (FTIR), assay and dissolution. Before exposure to stability condition, dissolution ranged from 78.0 ± 2.3 to 81.9 ± 3.5%, and 72.7 ± 2.0 and 75.9 ± 5.8% in directly compressed and ethanol-granulated formulations, respectively. GPS amount of 10% caused a decrease in dissolution albeit insignificant (p > 0.05). The polymorphic forms of RFX were α and γ in directly compressed and ethanol-granulated formulations, respectively. There was a decrease in dissolution rate and extent after exposure to 40 °C/75% RH in directly compressed formulations. On the other hand, only dissolution rate was affected in ethanol-granulated formulations. The dissolution ranged from 52.8 ± 2.0 to 70.0 ± 3.0% in directly compressed formulations after four weeks exposure to 40 °C/75% RH exposure. A decrease in dissolution was linked to polymorphic transformation of the drug and GPS in the formulations after exposure to stability condition. XRPD and FTIR data indicated α to β transformation in directly compressed formulations while no polymorphic change was observed in ethanol-granulated formulations. In conclusion, this study clearly showed effect of formulation and manufacturing variables, and stability exposure on the polymorphic stability and dissolution of RFX, which may have clinical ramification. [ABSTRACT FROM AUTHOR]

The focus of the study was to understand the effects of formulation and process variables on the printlets quality manufactured by selective laser sintering (SLS) 3D printing. The Box-Behnken response surface methodology was used to evaluate effects of individual variables and combinations thereof. The formulation and process variables studied were printing chamber temperature (°C, X 1), laser scanning speed (mm/sec, X 2) and lactose monohydrate concentration (%, X 3). The responses studied were weight of printlets (mg, Y 1), hardness (N, Y 2), disintegration time (sec, Y 3) and dissolved drug fraction in 15 min (%, Y 4). The values of Y 1 , Y 2 , Y 3 and Y 4 varied from 170.2–257.0 mg, 5.5–32.0 N, 20–120 s and 64.4–97.5%, respectively. The studied factors showed statistically significant effects on the dependent variables (p < 0.04). The correlation coefficient between empirical and model predicted values for Y 1 , Y 2 , Y 3 and Y 4 were 0.999, 0.992, 0.998 and 0.983, respectively. The model was validated by an independent experiment and actual values of the responses were in close agreement with model predicted values. Fourier transformed infrared spectroscopy indicated no chemical interactions between the components of the formulation during printing process. X-ray powder diffractograms suggested a decrease in crystallinity of the drug and lactose in the printlets. Chemical images indicated uniform distribution of the drug. Scanning electron microscopy and X-ray micro-CT scanning showed a very porous microstructure of the printlets with a porosity of about 37.89%. In conclusion, the SLS method of manufacturing provides a feasible and flexible avenue for fabricating dosage forms with tailored characteristics. [ABSTRACT FROM AUTHOR]