Tumor markers are substances, usually proteins, produced by the body in response to cancer growth, or by the cancer tissue itself. They can be detected in blood, urine, or tissue samples, and the discovery and detection of tumor markers may provide earlier diagnosis of cancer and improved therapeutic intervention. Colorimetric immunoassays for tumor marker detection have attracted considerable ...

We present a novel reflectance-based colorimetric aptasensor using gold nanoparticles for the detection of oxytetracycline for the first time. It was found that the reflectance-based measurement at two wavelengths (650 and 520 nm) can generate more stable and sensitive signals than absorbance-based sensors to determine the aggregation of AuNPs, even at high AuNP concentrations. One of the most ...

We describe applications of a colorimetric assay based on supramolecular assemblies of lipid-polydiacetylene vesicles for analysis and screening of membrane interactions of lipophilic enzymes, peptides, and ions and for study of the effects of lipid composition upon membrane properties. The lipid-polymer aggregates undergo visible and quantifiable blue-to-red transitions following interfacial i...

Carbohydrate molecules are involved in many of the cellular processes that are important for life. By combining the specific analyte targeting of carbohydrates with the multivalent structure and change of solution colour as a consequence of plasmonic interactions with the aggregation of metal nanoparticles, glyconanoparticles have been used extensively for the development of bioanalytical assay...

This study proposes a vision model for individual colorimetric observers. The proposed model can be beneficial in many color-critical applications such as color grading and soft proofing to assess ranges of color matches instead of a single average match. We extended the CIE 2006 physiological observer by adding eight additional physiological parameters to model individual color-normal observer...

In the past few years there has been renewed interest in the study of serum cholinesterase in various disease states, particularly those affecting the liver. Recently, a colorimetric method for the determination of this enzyme in the serum was reported by Ravin, Tsou, and Seligman (1). Their method, simple to perform, is as accurate as the gastrometric technique and more specific than the elect...

Esteban Gonzalez Burchard and colleagues explore how making medical research more diverse would aid not only social justice but scientific quality and clinical effectiveness, too.

The cytotoxicity of the biomaterials is a key issue that should be addressed prior to pre-clinical applications. This study was designed to evaluate and compare the cytotoxixity of two forms of bioactive glasses:nanopowder and micropowder. Human HGF1-PI53 gingival fibroblast cells were used to evaluate the cytotoxicity of 0.5, 1, 1.5, 2, 5, 10, 15 and 20 mg/ mL concentrations of the two bioacti...

OBJECTIVE To incorporate the first polymerase chain reaction (PCR) assay for Calymmatobacterium granulomatis into a colorimetric detection system for use in routine diagnostic laboratories. METHODS A capture oligonucleotide specific for the Klebsiella phoE gene was covalently linked to tosyl activated magnetic beads. Biotinylated phoE PCR products obtained from 14 positive specimens from pati...

In the context of print quality and process control colorimetric parameters and tolerance values are clearly defined. Using more than one color measurement instrument measuring the same color wedge can produce clearly different results due to random and systematic errors of the instruments. In certain situations where one instrument gives values which are just inside the given tolerances and an...