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Two novel methods of measuring the dimensions of oral lesions are described, which would be of help in deciding relative efficacies of different therapeutic agents when used in clinical trials after larger studies quantitatively assessed for inter/intraobserver variability.

Nanomaterials with different characteristics are offering many ingenious sensing approaches with interest for simple and disposable paper-based (bio)sensing applications. In this study, the colorimetric discrimination of alanine enantiomers is examined and, more importantly, AuNPs-embedded paper-based lab-in-a-syringe (LIS) device is developed as a sensing strategy. The LIS consists of two cellulose acetate membranes: the conjugate pad capturing the analyte and the detection pad signaling the presence of the captured analyte, both are sandwiched between reusable plastic filter holders connected to a disposable syringe. The principle of LIS assay is based on the enantioselective interaction occurring between the inherently chiral AuNPs and enantiomers in the first filter holder, which results in aggregation of AuNPs to give a distinct colour change from red to purple in solution and finally the aggregated AuNPs is kept on the detection pad through vertical-flow operation. AuNPs show an enantioselective recognition response toward L-Alanine and limit of detection (LOD) value is determined as 0.77 mM. In addition, we demonstrate the efficiency of the LIS device for detecting L-Alanine in human serum. The proposed LIS assay has some advantages such as useful for naked-eye observation, disposable, not time-consuming, inexpensive, no need of advanced instruments, easy to prepare and easy to handle. In the field, the approach which is the first demonstration of applicability of LIS device to show simple colorimetric enantioselective sensing of chiral species with a fast readout in less than 5 min is truly new and may have broad interest in enantiosensing of various chiral molecules.

A method for patterning narrow lines of biomolecules onto nitrocellulose membranes using laboratory syringe pumps is described. One syringe pump is used to drive the biomolecule solution through a needle, while another modified syringe pump acts as a one-dimensional translation stage, moving the needle across the membrane much like a pen. This method consumes very small volumes of reagents, and is a viable option for laboratory-scale fabrication and prototyping of point-of-care rapid diagnostic test strips.

The present study was undertaken to compare the calibration curve of the periotron* (HAR-6000) with those of two earlier models (HAR-600) instrument, which was found to be appreciably more sensitive in detecting small volumes of fluid than the two older models, is curvilinear in shae while the latter two models display linear calibration characteristics Calibration curves were also obtained for one of the HAR-600 models with the periopaper strip inserted up to and beyond the manufactures recommendations. The results obtained in this case differed from those published by others. Using fluids possessing different dielectric dissipation constants, calibration curves were determined for the HAR-6000 model over a wide range of volumes, The calibration data obtained best fitted quadratic functions and the relative positions of the curves on the axes are in the correct relationship to their dielectric constants Inter-instrument and other variations have once more stressed the importance of individual instrument calibration by uers.