We evaluated alamarBlue as a metabolic indicator in a standardized assay for the measurement of serum bactericidal activity (SBA) to Haemophilus influenzae type b (Hib) using sera containing natural and vaccine-induced anticapsular (polyribosylribitol phosphate) antibodies. SBA assays with a colorimetric and a fluorometric end point in the presence of alamarBlue were developed and compared to a...

Recently, novel data-driven offset-sparsity decomposition (OSD) method was proposed by us to increase colorimetric difference between tissue-structures present in the color microscopic image of stained specimen in histopathology. The OSD method performs additive decomposition of vectorized spectral images into image-adapted offset term and sparse term. Thereby, the sparse term represents an enh...

The selective complexation of cationic species was the earliest goal of supramolecular chemistry and continues to attract effort and interest. Over the last five years, Gunnlaugsson and co-workers at Trinity College Dublin have produced a wide variety of colorimetric sensors for ions, nucleic acids and oligonucleotides. In 2004, this group reported the synthesis of a colorimetric sensor for Cu(...

VARIETY of methods is available for tue colorimetric determination of uric acid. In general, these are based on precipitation of proteins, followed by the reduction in an alkaline medium of phosphotungstate by the uric acid ill the protein-free filtrate. Results of colorimetric determinations may at times vary from “true” uric acid values as determined by unease methods. This is because the col...

The colorimetric organization of RGB color images is investigated through the computation of the correlation integral of their three-dimensional histogram. For natural color images, as a common behavior, the correlation integral is found to follow a power law, with a noninteger exponent characteristic of a given image. This behavior identifies a fractal or multiscale self-similar distribution o...

A flexible nanoparticle-based sulfate assay is demonstrated in which the positively-charged gold nanoparticles (cysteamine-AuNPs) act as indicator. The aggregation of cysteamine-AuNPs is selectively induced by sulfate, which allows the rapid colorimetric sensing of sulfate without any precipitant, sample preparation and specific instruments. In this work, the cysteamine-AuNPs probe has been suc...

A chemiluminescence enzyme immunoassay based on magnetic microparticles (MmPs-CLEIA) was developed to evaluate serum α-fetoprotein (AFP) in parallel with traditional colorimetric enzyme-linked immunosorbent assay (ELISA). A systematic comparison between the MmPs-CLEIA and colorimetric ELISA concluded that the MPs-CLEIA exhibited fewer dosages of immunoreagents, less total assay time, and better...

A new application of gold nanoparticles (AuNPs) as a colorimetric method for gene detection of α-thalassemia 1 (SEA deletion) is reported here for the first time. This technique is based on color changes from salt-induced aggregation of un-hybridized nanogold probes after hybridization with the target DNA. Specific DNA probes were synthesized, thiol modified and conjugated on the surface of AuN...

The development of a green and facile strategy for synthesizing high stable gold nanoparticles (AuNPs) is still highly challenging. Additionally, the main problems regarding AuNPs based colorimetric sensors are their poor selectivity and low sensitivity, as well their tendency to aggregate during their synthesis and sensing process. Herein, we present an in-situ reduction strategy to synthesize...