Lubricant-Sensitivity Assessment of SPRESS® B820 by Near-Infrared Spectroscopy: A Comparison of Multivariate Methods.

The predictability of multivariate calibration models, calculated with offline near-infrared spectroscopy (NIRS), assessing impact of magnesium stearate (MgSt) fraction, blending time, and compression force on the tablet breaking force (TBF) of SPRESS® B820 was statistically compared. Tablets of lubricated SPRESS® B820 were prepared by varying lubrication and compression conditions using 24 full factorial design. Tablets were scanned in reflection mode on a benchtop NIRS. A qualitative principal component analysis and quantitative principal component regression (PCR) and partial least square (PLS) regression relationship between lubricant concentration, blending time, compression force, preprocessed NIR spectra, and measured TBF was calculated with calibration data set. The predictability of calibration models was validated with independent data set. Expected qualitative correlations between MgSt blending time and TBF and a nonlinear relationship between MgSt fraction and TBF were observed. Predictability of PLS comprehensive (0.25%-1% w/w MgSt) model was significantly different from individual 0.25%, 0.5%, and 1.0% w/w MgSt PLS models. In addition, PLS calibration models' predictability was different from PCR calibration models. Thus, added lubrication fraction and adopted multivariate methodology should be selected carefully during the calibration and validation stages as it may have a significant impact on the predictability of the developed models.

Preparation and Evaluation of Phospholipid-Based Complex of Standardized Centella Extract (SCE) for the Enhanced Delivery of Phytoconstituents.

In the present study, a phospholipid-based complex of standardized Centella extract (SCE) was developed with a goal of improving the bioavailability of its phytoconstituents. The SCE-phospholipid complex was prepared by solvent evaporation method and characterized for its physicochemical and functional properties. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), photomicroscopy, and powder x-ray diffraction (PXRD) were used to confirm the formation of Centella naturosome (CN). The prepared complex was functionally evaluated by apparent solubility, in vitro drug release, ex vivo permeation, and in vivo efficacy studies. The prepared CN exhibited a significantly higher (12-fold) aqueous solubility (98.0 ± 1.4 µg/mL), compared to the pure SCE (8.12 ± 0.44 µg/mL), or the physical mixture of SCE and the phospholipid (13.6 ± 0.4 µg/mL). The in vitro dissolution studies revealed a significantly higher efficiency of CN in releasing the SCE (99.2 ± 4.7, % w/w) in comparison to the pure SCE (39.2 ± 2.3, % w/w), or the physical mixture (42.8 ± 2.09, % w/w). The ex vivo permeation studies with the everted intestine method showed that the prepared CN significantly improved the permeation of SCE (82.8 ± 3.7, % w/w), compared to the pure SCE (26.8 ± 2.4, % w/w), or the physical mixture (33.0 ± 2.7, % w/w). The in vivo efficacy studies using the Morris Water Maze test indicated a significant improvement of the spatial learning and memory in aged mice treated with CN. Thus, drug-phospholipid complexation appears to be a promising strategy to improve the aqueous solubility and bioavailability of bioactive phytoconstituents.

Correlation of Structural and Macroscopic Properties of Starches with Their Tabletability Using the SM(2) Approach.

The effects of PURE-DENT® and SPRESS® starch properties on their compression behavior was characterized using "SM(2) " approach (structural properties, macroscopic properties, and multivariate analysis). Moisture sorption rate constants, moisture content, amylose and amylopectin degradation enthalpy, percent crystallinity, amylose-amylopectin ratio, and cross-linking degree were used to profile starch structural properties. Particle density, particle size distribution, and Heckel compression descriptors [yield pressure (YP) of plastic deformation, and elastic recovery] were used as macroscopic descriptors. The structural and macroscopic properties were correlated qualitatively [principal component analysis (PCA)] and quantitatively [standard least square regression (SLSR)] with the tablet mechanical strength (TMS). These analyses revealed that the differences correlated with amylose-amylopectin content, particle density, compression mechanisms, and TMS between the starch grades. Univariate analysis proved lacking; however, PCA identified the particle size, moisture content, percent crystallinity, amylose-amylopectin ratio, and YP of plastic deformation and elastic recovery as the main factors influencing the starch TMS. SLSR quantified the positive influence of Fourier transform infrared spectra absorbance ratio at 1022-1003 and YP of the immediate elastic recovery, and the negative contribution of amylopectin content on the TMS. Therefore, starch amylose and amylopectin content, crystallinity, and lower elastic recovery are mainly responsible for better TMS.