An Optical Overview of Poly[μ2-L-alanine-μ3-nitrato-sodium(I)] Crystals

Single crystals of the semiorganic materials, L-alanine sodium nitrate (LASN) and D-alanine sodium nitrate (DASN), were grown from an aqueous solution by slow-evaporation technique. X-ray diffraction (XRD) studies were carried for the doped grown crystals. The absorption of these grown crystals was analyzed using UV-Vis-NIR studies, and it was found that these crystals possess minimum absorption from 200 to 1100 nm. An infrared (FTIR) spectrum of single crystal has been measured in the 4000–400 cm−1 range. The assignment of the observed vibrational modes to corresponding symmetry type has been performed. A thermogravimetric study was carried out to determine the thermal properties of the grown crystal. The efficiency of second harmonic generation was obtained by a variant of the Kurtz-Perry method

The cientificWorldJOURNAL Research Article An Optical Overview of Poly[µ 2 -L-alanine-µ 3 -nitrato-sodium(I)] Crystals

Single crystals of the semiorganic materials, L-alanine sodium nitrate (LASN) and D-alanine sodium nitrate (DASN), were grown from an aqueous solution by slow-evaporation technique. X-ray diffraction (XRD) studies were carried for the doped grown crystals. The absorption of these grown crystals was analyzed using UV-vis-NIR studies, and it was found that these crystals possess minimum absorption from 200 to 1100 nm. An infrared (FTIR) spectrum of single crystal has been measured in the 4000-400 cm −1 range. The assignment of the observed vibrational modes to corresponding symmetry type has been performed. A thermogravimetric study was carried out to determine the thermal properties of the grown crystal. The efficiency of second harmonic generation was obtained by a variant of the Kurtz-Perry method

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data