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Excipient plays an essential role in drug delivery system, which promotes the drug to reach a particular site of action. Excipients directly or indirectly affect the duration and rate of drug release and absorption. In the current study, physicochemical properties, flow properties and release characteristics of native and modified pink potato starches were investigated to determine their excipient characteristics. Amylose content, water holding capacity, swelling and solubility properties were found to increase after pregelatinization and retrogradation. The SEM micrographs reveals the loss of granular structure of native after thermal modification. The FT-IR study confirms the gelatinization characteristics of the pregelatinized starch. X-ray diffraction pattern confirms the reduction of crystallinity after thermal modification. Tablets containing Paracetamol as a model drug showed that native, pregelatinized and modified pink potato starch could be useful for the manufacturing of immediate release formulation. [ABSTRACT FROM AUTHOR]

We have attempted comparative analysis of the utility of linear spectral unmixing (LSU) method and band ratios for delineating bauxite from laterite within the lateritic bauxite provinces of Chotonagpur Plateau, Jharkhand of India. This was attempted based on processing of visible–near infrared (VNIR) and shortwave infrared (SWIR) spectral bands of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor. In LSU method, spectral features of main constituent minerals of lateritic bauxite are used to decompose the pixel spectra to estimate the relative abundance of bauxite and laterite in each pixel to spatially delineate bauxite within laterite. We have also compared the bauxite map derived using LSU method with bauxite maps of two band ratios in terms of spatial disposition of bauxite. We also have attempted to relate the abundance values of pixels of LSU-based bauxite map with band ratio values of bauxite pixels of two selected bauxite indices. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Need for natural sustained releasing starches as pharmaceutical excipient. [•] Characterization of starches of different cultivars of Colocasia, from Jharkhand. [•] Isolated starches show high swelling power and water holding capacity. [•] In vitro studies reveals, release retardant properties of isolated starches. [ABSTRACT FROM AUTHOR]

Abstract: Starches were isolated from varieties of Dioscorea (Da1, Da2) grown in Jharkhand state of India and it was characterized in terms of moisture, ash, amylose content, bulk density, tapped density, true density, porosity, Carr''s index, Hausner''s ratio, swelling power, solubility, water holding capacity, paste clarity. Morphological, thermal and IR spectroscopic studies were also done to characterize the isolated starch. The shape and size of starch granules were round/oval to ellipsoid and 5–10μm. There were considerable differences in powder characteristics, amylose content, ash values, and water holding capacity, swelling and solubility power. Starch from variety Da2 showed high enthalpy of gelatinization temperature as compared to variety Da1. Peaks in FTIR spectra of both starches revealed its carbohydrate nature. In vitro studies revealed that both the starches from Da1 and Da2 can be used in developing sustained release formulations. The result showed that starches from both Dioscorea can be used in pharmaceutical industries as excipients with minimal modifications. [Copyright &y& Elsevier]

Abstract: Bauxite deposits of Jharkhand in India are resulted from the lateritization process and therefore are often associated with the laterites. In the present study, ASTER (Advanced Space borne Thermal Emission and Reflection Radiometer) image is processed to delineate bauxite rich pockets within the laterites. In this regard, spectral signatures of lateritic bauxite samples are analyzed in the laboratory with reference to the spectral features of gibbsite (main mineral constituent of bauxite) and goethite (main mineral constituent of laterite) in VNIR–SWIR (visible-near infrared and short wave infrared) electromagnetic domain. The analysis of spectral signatures of lateritic bauxite samples helps in understanding the differences in the spectral features of bauxites and laterites. Based on these differences; ASTER data based relative band depth and simple ratio images are derived for spatial mapping of the bauxites developed within the lateritic province. In order to integrate the complementary information of different index image, an index based principal component (IPC) image is derived to incorporate the correlative information of these indices to delineate bauxite rich pockets. The occurrences of bauxite rich pockets derived from density sliced IPC image are further delimited by the topographic controls as it has been observed that the major bauxite occurrences of the area are controlled by slope and altitude. In addition to above, IPC image is draped over the digital elevation model (DEM) to illustrate how bauxite rich pockets are distributed with reference to the topographic variability of the terrain. Bauxite rich pockets delineated in the IPC image are also validated based on the known mine occurrences and existing geological map of the bauxite. It is also conceptually validated based on the spectral similarity of the bauxite pixels delineated in the IPC image with the ASTER convolved laboratory spectra of bauxite samples. [Copyright &y& Elsevier]

In present time, photoacoustic spectroscopy (PAS) has become a popular technique for measurements of thermal properties of biological, chemical, geological samples. The PAS is suitable for any phase of material such as solid, liquid, gel, suspension and gas etc. In this work authors have fabricated a photoacoustic cell & a pre-amplifier, and optimized both for maximum photoacoustic (PA) signal. Optimum inert cavity volume of the cell was measured to 3.20 × 10 6 m3. After that, coals samples were collected from five different places of Jharkhand state, India for the study of their quality with PA spectroscopy. The X-ray diffraction (XRD) data has confirmed that four samples have different class of quartz and one sample is very close to kaolinite. The field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray analysis (EDAX) had shown non-uniform bulk like structure containing various elementals. All samples are distinguished by their quality using PAS and verified them with the Raman spectroscopy. Finally, the authors have measured thermal diffusivity of each samples. The maximum value of thermal diffusivity is measured for kaolinite structure having value of 13.4673 × 10–8 m2/s. [ABSTRACT FROM AUTHOR]

Increasing demand and considerable attention to the non-conventional sources of starches leads to explore new sources. Starches of Dioscorea (Da 1 and Da 2 ) from Jharkhand, North Eastern region of India have been studied for its physicochemical properties. An attempt has been made to study the carboxymethylated derivatives of starches from two varieties of Dioscorea of this region. Different concentration of monochloroacetate was used to study the effect of degree of substitution (DS) on the physicochemical properties of starches. A considerable effect of DS was noticed on the ash content, amylose content, water-holding capacity, swelling and solubility power of carboxymethylated derivatives. Morphological studies showed the increase in the deformation of structure of the starch granule with an increase in the degree of substitution. FTIR confirmed the carboxymethylation reaction. TGA data of carboxymethylated starches revealed the stability to the temperature. Micromeritics of starch powder and granules showed the value which makes these starches to be utilized as an excipient. With the increase in DS, the % release of drug was found to be decreased. This further makes the carboxymethyl derivatives of Dioscorea a good source to be used as an excipient for sustained release formulations. [ABSTRACT FROM AUTHOR]