15 December 2016:
CNBP researchers were at the forefront of this year’s Biofocus Conference held at Macquarie University, 15 December 2016.
Early career Centre researchers Annemarie Nadort, Lindsay Parker and Nima Sayyadi sat on the conference organising committee, Centre Deputy Director Ewa Goldys (pictured) opened proceedings while CNBP Chief Investigator Prof Andrew Abell (from the University of Adelaide) delivered an extremely well received plenary talk titled, “Defining biomolecular structure and function in solution and on surfaces: new therapeutics and biological probes.”
The annual conference provides a platform for the multidisciplinary community at Macquarie University to present and communicate research, discuss research outcomes and facilitate interdisciplinary collaborations spanning the fields of of biomedical sciences, biomedical engineering, physics, chemistry and medicine.
Feedback from attendees at this year’s event was extremely positive with plenty of formal and informal scientific discussion taking place between sessions.
5 September 2016:
The latest paper published by CNBP researchers (lead author Nima Sayyadi, pictured left), reports on a bright red water soluble luminescent molecular probe that was successfully synthesized, with multiple platforms developed for sensitive immunodetection of prostate cancer cells. The probe has immediate potential for sensitive detection of a wide range of proteins and disease-specific cellular antigens.
Journal: Analytical Chemistry.
Publication title: Sensitive time-gated immunoluminescence detection of prostate cancer cells using a TEGylated europium ligand.
Authors: Nima Sayyadi, Irene Justiniano, Russell Edwin Connally, Run Zhang, Bingyang Shi, Liisa Kautto, Arun V Everest-Dass, Jingli Yuan, Bradley John Walsh, Dayong Jin, Robert Drant Willows, James A. Piper, and Nicolle H. Packer.
Abstract: We describe the application of a synthetically developed tetradentate β-diketonate-europium chelate with high quan-tum yield (39%), for sensitive immunodetection of prostate cancer cells (DU145). MIL38 antibody, a mouse monoclonal antibody against Glypican 1, conjugated directly to the chelate via lysine residues, resulted in soluble (hydrophilic) and stable immunoconjugates. Indirect labeling of the antibody by a europium chelated secondary polyclonal antibody and a streptavidin/biotin pair was also performed. All of these bright luminescent conjugates were used to stain DU145 cells, a prostate cancer cell line, using time gated luminescence microscopy for imaging, and their performances were compared to conventional FITC labelling. For all prepared conjugates, the europium chelate in conjunction with a gat-ed auto-synchronous luminescence detector (GALD) completely suppressed the cellular autofluorescence background to allow capture of vivid, high contrast images of immune-stained cancer cells.
The paper is available online.
10 June 2016:
CNBP and Macquarie University researchers have successfully developed a novel indirect universal detection reagent that rapidly labels antibodies with luminescence within seconds and without the need for any complicated bioconjugation procedures. The reagent, reported in the journal ‘Scientific Reports’, can be used to directly label antibodies for several time-gated luminescence applications, e.g., bioimaging, cell labeling and detection, and flow cytometry.
The work was co-authored by CNBP researchers Dr Andrew Care and Dr Nima Sayyadi and led by CNBP Associate Investigator Dr Anwar Sunna.
Pictured (top left) – giardia cyst cells labeled with europium chelate.
Publication title: A Novel Universal Detection Agent for Time-Gated Luminescence Bioimaging
Authors: Nima Sayyadi and Andrew Care ( first co-authors), Russell E. Connally, Andrew C. Try, Peter L. Bergquist and Anwar Sunna
Luminescent lanthanide chelates have been used to label antibodies in time-gated luminescence (TGL) bioimaging. However, it is a challenging task to label directly an antibody with lanthanide-binding ligands and achieve control of the target ligand/protein ratios whilst ensuring that affinity and avidity of the antibody remain uncompromised. We report the development of a new indirect detection reagent to label antibodies with detectable luminescence that circumvents this problem by labelling available lysine residues in the linker portion of the recombinant fusion protein Linker-Protein G (LPG). Succinimide-activated lanthanide chelating ligands were attached to lysine residues in LPG and Protein G (without Linker) and the resulting Luminescence-Activating (LA-) conjugates were compared for total incorporation and conjugation efficiency. A higher and more efficient incorporation of ligands at three different molar ratios was observed for LPG and this effect was attributed to the presence of eight readily available lysine residues in the linker region of LPG. These Luminescence-Activating (LA-) complexes were subsequently shown to impart luminescence (upon formation of europium(III) complexes) to cell-specific antibodies within seconds and without the need for any complicated bioconjugation procedures. The potential of this technology was demonstrated by direct labelling of Giardia cysts and Cryptosporidium oocysts in TGL bioimaging.
The paper is available online.
25 May 2016:
Dr. Nima Sayyadi at Macquarie University, former CNBP Associate Investigator, has been employed as a CNBP Research Fellow.
Dr Sayyadi has previously been responsible for designing and developing a series of novel europium luminescent chelates which have successfully been applied to the detection of Staphylococcus aureus using luminescent in situ hybridization (LISH) techniques. He has also developed europium chelates using different immunoconjugate platforms for sensitive TGL detection of a wide range of bacteria, protozoa and human cancer cells.
His new CNBP related activity will involve exploring the synthesis and application of novel lanthanide chelates for the sensitive time-gated luminescence (TGL) detection of bio-targets in complex biological matrices.
More specifically Dr Sayyadi’s activity will be focused on the following –
* Synthesis of Europium chelate molecules with different conjugation functionality e.g. amino, sulphydryl, alkyne, hydrazide.
* Conjugation of Europium chelates to protein, sugars, nucleic acids, and characterization of the conjugates.
* Testing and application of time-gated orthogonal scanning automated microscopy (OSAM) and standing microscope (when developed) for single cell detection of Europium chelates
* Time-gated luminescent immunodetection (using IgG and IgM) for detection of target proteins in biological samples (urine, blood, and saliva).
Well done on the gaining of your new role Nima!
23 November 2015:
CNBP researcher Nima Sayyadi is first author on a recently published paper titled, ‘A novel biocompatible europium chelate for sensitive time-gated immunodetection.’
The paper was published in the journal Chemical Communications.
Abstract: We describe the synthesis of a novel hydrophilic derivative of a tetradentate β-diketone europium chelate that was used to prepare an immunoconjugate probe against Giardia lamblia cysts. We used a Gated Autosynchronous Luminescence Detector (GALD) to obtain high quality delayed luminescence images of cells 30-fold faster than ever previously reported.
Additional information can be found online here.
28 April 2015:
CNBP Associate Investigator, Dr Nima Sayyadi from Macquarie University, gave a well received seminar at the University of Adelaide on the topic, “Sensitive Cancer Immunodetection Using a Novel Europium Immunoconjugate.”
The seminar, on April 28th, 2015 was part of a week long visit to the University of Adelaide for Nima, who spent a large part of that time working with CNBP’s Dr Jingxian Yu in the Recognise team.
As a CNBP AI, the major aim of Nima’s current project is in aiding the development of luminescent probes for bio-sensing.