Abstract: An electrochemical screening method for the selection of DNA aptamers against 11-deoxycortisol (11-DCL) using gold electrode for target immobilization is described. The gold electrode is used as solid matrix instead of the beads for SELEX. The selection steps (SELEX) are performed on the 11-DC modified electrode directly as the DNA library in the first round or the enriched DNA pools in the subsequent rounds were incubated on the electrode, then the unbound DNA is washed and the bound DNA is measured directly by square wave voltammetry. Then elution of the bound DNA is performed for further use.

Abstract: There is provided a biosensor for detecting pathogens in a sample. The detection is based on colorimetry. The biosensor comprises one or more particle supports and a magnetic material attached to a planar support. The biosensor embodies magnetic particles that are functionalized using a chemical substrate specific to the pathogens to be detected. The sensor may allow for a simultaneous detection of a plurality of pathogens in the sample. Also, the sensor may be disposable. Moreover, the sensor may be integrated in a portable detection device.

Abstract: A multiplex hand-held diagnostic biosensor, using two inflammatory salivary biomarkers, Human Neutrophil Elastase (HNE) and Cathepsin-G, was constructed made to potentially detect Periodontitis at an early stage is described. The use of magnetic nanoparticle biosensor method used as a device was based on the measurement of proteolytic activity using specific proteases probes. The magnetic nanoparticle biosensor device is capable of specific and quantitative detection of HNE and Cathepsin-G in solution and in spiked saliva samples with a lower detection limit of 1 pg/mL and 100 fg/mL for HNE and Cathepsin-G, respectively.

Abstract: There is provided a method of detecting an analyte in a sample. The method is based on colorimetry and also on the binding affinity between the analyte and a chemical substrate which may be a recognition receptor thereof. The method involves a support and a colored carrier. A kit for use in the detection is also provided.

Abstract: High affinity DNA aptamers Seq ID#1-8 for HbA1C and tHb were successfully selected using SELEX after 11 rounds of selection. The tested aptamers bind to HbA1C with dissociation constants in the nanomolar range with the highest affinity aptamer, Seq ID#6, exhibiting a Kd of 2.8 nM. Another aptamer sequence (Seq ID #4) which showed high binding affinity to tHb with a Kd of 2.7 nM was also selected. The HbA1C and tHb-specific aptamers were then applied for the detection of HbA1C % using a voltammetric aptasensor array platform showing remarkable sensitivity and selectivity. The aptasensor array platform was validated using standard human whole blood samples and demonstrated linearity over wide concentration range. The developed platform is superior to current methodologies due to its simplicity, stability and lower cost which will facilitate the early and accurate diagnosis of diabetes.

Abstract: High affinity DNA aptamers Seq ID#1-8 for HbA1C and tHb were successfully selected using SELEX after 11 rounds of selection. The tested aptamers bind to HbA1C with dissociation constants in the nanomolar range with the highest affinity aptamer, Seq ID#6, exhibiting a Kd of 2.8 nM. Another aptamer sequence (Seq ID #4) which showed high binding affinity to tHb with a Kd of 2.7 nM was also selected. The HbA1C and tHb-specific aptamers were then applied for the detection of HbA1C % using a voltammetric aptasensor array platform showing remarkable sensitivity and selectivity. The aptasensor array platform was validated using standard human whole blood samples and demonstrated linearity over wide concentration range. The developed platform is superior to current methodologies due to its simplicity, stability and lower cost which will facilitate the early and accurate diagnosis of diabetes.

Abstract: A multiplex hand-held diagnostic biosensor, using two inflammatory salivary biomarkers, Human Neutrophil Elastase (HNE) and Cathepsin-G, was constructed made to potentially detect Periodontitis at an early stage is described. The use of magnetic nanoparticle biosensor method used as a device was based on the measurement of proteolytic activity using specific proteases probes. The magnetic nanoparticle biosensor device is capable of specific and quantitative detection of HNE and Cathepsin-G in solution and in spiked saliva samples with a lower detection limit of 1 pg/mL and 100 fg/mL for HNE and Cathepsin-G, respectively.

Abstract: There is provided a method of detecting an analyte in a sample. The method is based on colorimetry and also on the binding affinity between the analyte and a chemical substrate which may be a recognition receptor thereof. The method involves a support and a colored carrier. A kit for use in the detection is also provided.

Abstract: There is provided a biosensor for detecting pathogens in a sample. The detection is based on colorimetry. The biosensor comprises one or more particle supports and a magnetic material attached to a planar support. The biosensor embodies magnetic particles that are functionalized using a chemical substrate specific to the pathogens to be detected. The sensor may allow for a simultaneous detection of a plurality of pathogens in the sample. Also, the sensor may be disposable. Moreover, the sensor may be integrated in a portable detection device.

Abstract: There is provided a portable device for detecting pathogens in a sample, the detection being based on an assay involving one or more reagents and heat. The device comprises a flexible substrate having a plurality of spaced apart reservoirs along its length, each reservoir adapted for receiving reagents and the sample, the substrate being secured to a pair of spaced apart reels and movable there between by rolling. Also, the device comprises heating means which can be secured to one of the two reels.

Abstract: The present invention relates to the field of biosensors useful for detecting bacteria. More particularly, the present invention relates to an electrochemical cell or biosensor and its use in a phage-based method and kit for the detection of bacteria.

Abstract: A novel single point leaky waveguide structure and its use as an optical sensor for the detection of particles is disclosed. The waveguide structure is fabricated to increase the overlap of the evanescent field extension from the sensor surface with particles in the bulk solution of a flowing system so as to place most of the volume of the particles within the evanescent field. Increasing the overlap of the evanescent field with the particles and permitting mode propagation along the direction of flow for a few millimetres provides an effective interrogation approach for multiple particle detection in a single flow channel.

Abstract: Apparatus for detecting particles in a liquid, comprises an evanescent optical sensor having an electrically conducting layer, and means associated therewith for providing an electric field at or adjacent the sensor surface. Preferably, the optical sensor is a surface bound sensor based on a metal-clad leaky waveguide structure. A DC potential applied to the metal layer and a parallel counter electrode provides a uniform electric field, which drives deposition of the particles on the sensor surface. Alternatively, an alternating potential applied to a electrically conducting layer configured as an electrode and counter electrode induces an electro-osmotic bulk flow in the liquid which drives deposition of the particles on the sensor surface.

Abstract: A novel single point leaky waveguide structure and its use as an optical sensor for the detection of particles is disclosed. The waveguide structure is fabricated to increase the overlap of the evanescent field extension from the sensor surface with particles in the bulk solution of a flowing system so as to place most of the volume of the particles within the evanescent field. Increasing the overlap of the evanescent field with the particles and permitting mode propagation along the direction of flow for a few millimetres provides an effective interrogation approach for multiple particle detection in a single flow channel.