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Hammami M.,National Institute of Research and Physicochemical Analysis INRAP | Soussou A.,National Institute of Research and Physicochemical Analysis INRAP | Soussou A.,University of Bordeaux 1 | Soussou A.,University of Monastir | And 4 more authors.
IEEE Transactions on Nanobioscience | Year: 2015

As a potential biomarker for the investigation of cancer inflammatory profiles, macrophage mannose receptor (MMR, CD206) is herein selected to develop an immunosensor based on layered double hydroxide (LDH). Like an endocyte C-type lectin receptor, MMR plays an important role in immune homeostasis by scavenging unwanted mannose glycoproteins. It attracts a progressive attention thanks to its particularly high expression within the tumor microenvironment. There is a great of interest to develop an immunosensor based on an antibody specific to MMR for detection of stroma versus tumor cells. In this work, we studied the feasibility of high sensitive MMR cancer Screen Printed Electrode (SPE) immunosensor. Working electrode of commercialized SPE was modified by immobilization of specific antibody (anti-MMR) into thin layer of LDH nanomaterials. Structural, morphological, and surface properties of LDHs were studied by X-Ray diffraction, atomic force microscopy and Infrared spectroscopy in ATR. Cyclic Voltammetry technique was used to study interaction between the human recombinant MMR protein (rHu-MMR, NSO derived) and an immobilized antibody into developed immunosensor. High specific response of -11.72 μA/ng.mL-1 (with a correlation coefficient of R2=0.994 ) were obtained in linear range of 0.05 ng/mL to 10.0 ng/mL of specific recombinant antigen. The limit of detection (LOD) was less than 15.0 pg/mL. From these attractive results, the feasibility of an electrochemical immunosensor for cancer was proved. Additional experiments to study stability and reproducibility the immunosensor should be completed in perspective to use these anti-MMR based immunosensors for sensing human MMR in patient biopsies and sera. © 2015 IEEE.


Temani M.,National Institute of Research and Physicochemical Analysis INRAP | Baccar Z.M.,National Institute of Research and Physicochemical Analysis INRAP | Mansour H.B.,Institute Superieur Of Biotechnologie
Microelectronic Engineering | Year: 2014

In the current study, we aimed to immobilize cholesterol oxidase (ChOx) on Layered Double Hydroxide (LDH) for cholesterol sensing. Obtained results have shown that immobilized ChOx keeps its activity even after several uses. However, some free radicals, such as hydrogen peroxide (H2O2), were generated through the enzymatic activity. In this work, we investigated the effects of hexane extract from Acacia salicina toward free radical scavenging activity. Hexane extract was an effective inhibitor of H2O 2 generated by the enzymatic cholesterol/cholesterol oxidase catabolism (inhibition percentage ≈ 40%). This activity could be attributed to the presence of phytosterols in this extract. The present study demonstrates that extracts of A. salicina leaves are a potential source of antioxidant agents (most likely sterols compounds), their antioxidant activity might be used in chemoprevention trials. © 2014 Elsevier B.V. All rights reserved.


Hidouri S.,National Institute of Research and Physical and Chemical Analysis INRAP | Hidouri S.,University of Carthage | Hidouri S.,National Institute of Research and Physicochemical Analysis INRAP | Baccar Z.M.,National Institute of Research and Physical and Chemical Analysis INRAP | And 4 more authors.
Talanta | Year: 2011

This work describes the use of layered double hydroxides (LDHs) for the immobilisation of acetylcholinesterase (AChE) on insulator/semiconductor solid supports. Different LDHs have been synthesised by a co-precipitation method. Afterwards, biohybrid materials based on AChE-LDH mixtures have been produced using wild and recombinant enzymes. Spectroscopic techniques have confirmed the LDH phase identity and the links created between the LDH and AChE. Spectrophotometric assays have demonstrated that most of the biohybrid materials are functional and stable. Several configurations have been used for AChE immobilisation. The highest catalytic responses have been observed when using wild enzyme and immobilising AChE-LDH mixtures on LDHs previously deposited on the solid supports. LDHs have been demonstrated to be suitable host matrices for AChE immobilisation on electrodes for the subsequent development of electrochemical biosensors. © 2011 Elsevier B.V. All rights reserved.


Baccar Z.M.,National Institute of Research and Physicochemical Analysis INRAP | Caballero D.,University of Barcelona | Eritja R.,CSIC - Institute of Advanced Chemistry of Catalonia | Eritja R.,Barcelona Institute for Research in Biomedicine | Errachid A.,CNRS Analytical Sciences Lab
Electrochimica Acta | Year: 2012

DNA testing requires the development of sensitive and fast devices to measure the presence of nucleic acid sequences by DNA hybridization. In this paper, a simple and label-free DNA-biosensor has been investigated based on the detection of DNA hybridization on layered double hydroxide (LDH) nanomaterials with special emphasis on targeting long single stranded DNA sequences. First, the immobilization of a 20 bases long DNA probe on a thin layer of Mg 2AlCO 3 and Mg 3AlCO 3 LDH was studied. Then, DNA hybridization reaction was detected by means of Electrochemical Impedance Spectroscopy. The resulting biosensor showed a high sensitivity for the detection of 80 bases long DNA complementary sequences. The dynamic range was 18-270 ng/ml with a detection limit lower than 1.8 ng/ml. © 2012 Elsevier Ltd.


Baccar Z.M.,National Institute of Research and Physicochemical Analysis INRAP | Hidouri S.,National Institute of Research and Physicochemical Analysis INRAP | Errachid A.,CNRS Analytical Sciences Lab | Sanchez O.R.,University of Barcelona
Journal of Nanoscience and Nanotechnology | Year: 2011

In this work, we present the development of a hybrid biomembrane based on the immobilization of diamine oxidase (DAO) into LDH thin films for histamine detection. The LDHs preselected as host matrixes are: hydrotalcites (Mg 2Al(CO 3) 0.5(OH) 6), Iowaite (Mg 4Fe(OH) 10Cl) and hydrocalumite (Ca 2Al(OH) 6Cl). The immobilized probes were characterized by atomic force microscopy (AFM) and attenuated total reflection infrared spectroscopy (IR-ATR mode). The analysis of these results shows that the immobilization of DAO occurs with all type of selected LDH and is stable after a 7 day-immersion in phosphate buffer solution. The LDH incorporating magnesium or calcium divalent cations present high-quality surface topology for DAO immobilization and the ability to keep the enzyme in a well conformation for biogenic amines catabolism and histamine detection. Copyright © 2011 American Scientific Publishers. All rights reserved.


PubMed | National Institute of Research and Physicochemical Analysis INRAP
Type: Journal Article | Journal: Journal of nanoscience and nanotechnology | Year: 2012

In this work, we present the development of a hybrid biomembrane based on the immobilization of diamine oxidase (DAO) into LDH thin films for histamine detection. The LDHs preselected as host matrixes are: hydrotalcites (Mg2Al(CO3)0.5(OH)6), lowaite (Mg4Fe(OH)10Cl) and hydrocalumite (Ca2Al(OH)6Cl). The immobilized probes were characterized by atomic force microscopy (AFM) and attenuated total reflection infrared spectroscopy (IR-ATR mode). The analysis of these results shows that the immobilization of DAO occurs with all type of selected LDH and is stable after a 7 day-immersion in phosphate buffer solution. The LDH incorporating magnesium or calcium divalent cations present high-quality surface topology for DAO immobilization and the ability to keep the enzyme in a well conformation for biogenic amines catabolism and histamine detection.

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