Solid Phase Microextraction (SPME) uses a small volume of sorbent dispersed typically on the surface of small fibres, to isolate and concentrate analytes from sample matrix. After contact with sample, analytes are absorbed or adsorbed by the fibre phase (depending on the nature of the coating) until an equilibrium is reached in the system. The amount of an analyte extracted by the coating at eq...

The use of antibodies in HPLC columns for on-line immunoextraction combined with reversed-phase liquid chromatography (RPLC) is of growing interest in environmental and agricultural analysis. This technique is typically performed by using a small RPLC precolumn to capture and concentrate analytes as they elute from the immunoextraction column; however, there is little information on the conditi...

Nanoparticle-ligand systems can be targeted to specific analytes to effect a change in the properties of the nanoparticles. We will examine two examples in which the electromagnetic properties of the nanoparticles (arising from their small size) are altered by analyte binding, and can be applied as a transducer in a chemical sensing system for explosive analytes. The first property reviewed is ...

The ability to quantify levels of target analytes in biological samples accurately and precisely in biomonitoring involves the use of highly sensitive and selective instrumentation such as tandem mass spectrometers and a thorough understanding of highly variable matrix effects. Typically, matrix effects are caused by co-eluting matrix components that alter the ionization of target analytes as w...

A comprehensive method was developed for the simultaneous analysis in human breast milk of 12 synthetic musks, five nitro musks, six polycyclic muks and one macrocyclic musk; as well as one musk metabolite and triclosan. The target analytes were freeze dried and extracted using the accelerated solvent extraction (ASE) procedure. The extracts were further purified by gel permeation chromatograph...

Plasma is a rich mine of various biomarkers including proteins, metabolites and circulating nucleic acids. The diagnostic and therapeutic potential of these analytes has been quite recently uncovered, and the number of plasma biomarkers will still be growing in the coming years. A significant part of the blood plasma preparation is still handled manually, off-chip, via centrifugation or filtrat...

We report a biosensing method that is based on magnetically immobilized functional liposomes. The vesicles encapsulate magnetic nanoparticles (MNP) and enzymatic sensing reagents. Magnetic attraction between MNP and external magnets first immobilizes liposomes onto the surface of a coverglass. With the assistance from α-hemolysin (aHL), translocations of analytes through a lipid membrane trigge...

Surface-enhanced Raman scattering (SERS) is a label-free and accurate analytical technique for the detection of broad range various analytes such as, biomolecules, pesticides, petrochemicals, as well cellular other biological systems. A key component SERS analysis substrate which required to be equipped with plasmonic features metal nanostructures that directly interact light targeted analytes....

We report a novel straightforward approach for simultaneous and highly-selective detection of multi-analytes (i.e. glucose, cholesterol and urea) using an integrated field-effect transistor (i-FET) array biosensor without any interference in each sensor response. Compared to analytically-measured data, performance of the ZnO nanorod based i-FET array biosensor is found to be highly reliable for...

Several classes of transmembrane protein ion channels function in vivo as sensitive and selective detection elements for analytes. Recent studies on single channels reconstituted into planar lipid bilayer membranes suggest that nanometer-scale pores can be used to detect, quantitate and characterize a wide range of analytes that includes small ions and single stranded DNA. We briefly review her...