Differential array sensing for cancer cell classification and novelty detection.

A series of semi-specific peptides reported in the literature to bind various epitopes on cell surfaces were used in a differential sensing array to pattern cell line identity. The peptides were conjugated to thiazole orange to act as both a fluorescence reporter and a DNA intercalator. Fluorescence data for the peptides exposed to cells, with and without exogenous double stranded DNA (dsDNA), led to chemometric fingerprints for eight cancer cell lines.

Next-generation sequencing as input for chemometrics in differential sensing routines.

Differential sensing (DS) methods traditionally use spatially arrayed receptors and optical signals to create score plots from multivariate data which classify individual analytes or complex mixtures. Herein, a new approach is described, in which nucleic acid sequences and sequence counts are used as the multivariate data without the necessity of a spatial array. To demonstrate this approach to DS, previously selected aptamers, identified from the literature, were used as semi-specific receptors, Next-Gen DNA sequencing was used to generate data, and cell line differentiation was the test-bed application.

Chiral amine enantiomeric excess determination using self-assembled octahedral Fe(II)-imine complexes.

A receptor assembly composed of iron(II) triflate and pyridine-2,6-dicarbaldehyde was used to determine the enantiomeric excess (ee) of alpha-chiral primary amines using circular dichroism spectroscopy. The alpha chiral amines condense with the dialdehyde to form a diimine, which forms a 2:1 octahedral complex with iron(II). The ee values of unknown concentrations of alpha-chiral amines were determined by constructing calibration curves for each amine and then measuring the ellipticity at 600 nm.