PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 15494252

Label-free amplified bioaffinity detection using terahertz wave technology.

Abdellah Menikh·Samuel P Mickan·Haibo Liu·Robert Maccoll·X-C Zhang
View original source ↗Export metadata ↓

Abstract

A new affinity biosensor based on pulsed terahertz (THz) wave technology has been used to monitor binding between biotin and avidin molecules. Amplified detection of avidin-biotin binding is obtained on supported membranes composed of biotin layers on quartz surface, which is modified with octadecanol. Agarose particles are conjugated with avidin and then applied to biotin, which is already bound to the octadecanol quartz surface, the biotin binds to the conjugate rapidly and causes an enhancement of the THz difference signal between biotin and biotin-avidin complexes by a factor greater than eight fold when compared to the same sample without agarose beads. The technique was able to detect less than 10.3 ng/cm2 avidin, thus, giving the THz system a detection capability of sub-thin solid films better than ellipsometry and reflectometry techniques. Further improvement is underway using highly refractive beads together with appropriate surface chemistry. This newly developed method is being saliently optimized for future application, including the detection of DNA hybridization and ligand-analyte affinity binding.

Explore related subjects

Affinity LabelsAvidinBiosensing TechniquesBiotinCoated Materials, BiocompatibleEquipment DesignEquipment Failure AnalysisMicrowavesProtein Interaction MappingEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Abdellah Menikh, Samuel P Mickan, Haibo Liu, Robert Maccoll, X-C Zhang. 2004-10-15. Label-free amplified bioaffinity detection using terahertz wave technology.. https://doi.org/10.1016/j.bios.2004.03.006

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

ProteomeBinders: planning a European resource of affinity reagents for analysis of the human proteome.

ProteomeBinders is a new European consortium aiming to establish a comprehensive resource of well-characterized affinity reagents, including but not limited to antibodies, for analysis of the human proteome. Given the huge diversity of the proteome, the scale of the project is potentially immense but nevertheless feasible in the context of a pan-European or even worldwide coordination.

Affinity Labels↗
PubMed2006

Synthesis of novel caspase inhibitors for characterization of the active caspase proteome in vitro and in vivo.

Caspases are cysteine proteases that are essential for cytokine maturation and apoptosis. To facilitate the dissection of caspase function in vitro and in vivo, we have synthesized irreversible caspase inhibitors with biotin attached via linker arms of various lengths (12a-d) and a 2,4-dinitrophenyl labeled inhibitor (13). Affinity labeling of apoptotic extracts followed by blotting reveals that these affinity probes detect active caspases. Using the strong affinity of avidin for biotin, we have isolated affinity-labeled caspase 6 from apoptotic cytosolic extracts of cells overexpressing procaspase 6 by treatment with 12c, which contains biotin attached to the N(epsilon)-lysine of the inhibitor by a 22.5 A linker arm, followed by affinity purification on monomeric avidin-sepharose beads. Compound 13 has proven sufficiently cell permeable to rescue cells from apoptotic execution. These novel caspase inhibitors should provide powerful probes for the study of the active caspase proteome during apoptosis both in vitro and in vivo.

Affinity Labels↗
PubMed2006

Removal of contaminating DNA from polymerase chain reaction using ethidium monoazide.

The presence of exogenous DNA in PCR reagents and DNA polymerase is a common occurrence. In particular, the amplification of 16S rRNA genes with universal primers for non-culture-based study is often hampered by the formation of false positives. Here, we describe the use of ethidium monoazide (EMA) to eliminate contaminating DNA in a polymerase chain reaction. The advantage of the proposed methodology is the retention of the highly sensitive nature of PCR with the ability to amplify template DNA at concentrations lower than those of contaminating DNA. The treatment of PCR master mix with EMA concentrations that exceeded those required to remove contaminating DNA can interfere with the amplification of low-template concentrations. The methodology presented is straightforward and can be accomplished within 10 min.

Affinity Labels↗