Sandy Shuo Zhao's research while affiliated with Université de Montréal and other places

Publications (11)

Article
A multi-channel fully integrated SPR biosensor was applied for the analysis of an anti-cancer drug, methotrexate (MTX) as a potential analytical tool used in clinical chemistry laboratories for therapeutic drug monitoring (TDM). MTX concentrations in a patient's serum undergoing chemotherapy treatments can be determined by surface plasmon resonance...
Chapter
Nanobiosensors exploiting the optical phenomenon of surface plasmon resonance (SPR) are ideal candidates for the design of optical sensors for clinical diagnostics. The label-free nature and sensitivity of SPR biosensors to binding events makes them generally applicable to the detection of a broad class of biomolecules. Recent advances in instrumen...
Article
The rapid, label-free and point-of-care detection of therapeutic drugs and other metabolites is of high importance for improving treatment of patients. SPR sensors were developed on a portable instrument for methotrexate, testosterone and antibiotic.
Article
Full-text available
We report that a shorter Debye length and, as a consequence, decreased colloidal stability are required for the molecular interaction of folic acid-modified Au nanoparticles (Au NPs) to occur on a surface-bound receptor, human dihydrofolate reductase (hDHFR). The interaction measured using surface plasmon resonance (SPR) sensing was optimal in a ph...
Article
Full-text available
Physical chemistry, materials science, analytical chemistry and engineering greatly contributed to the increasing popularity of bioanalytical and biophysical applications of surface plasmon resonance (SPR) by providing novel materials, surface chemistry, instrumental concepts, and theory to further understand the plasmonic phenomenon and support in...
Article
Ionic liquid self-assembled monolayers (SAM) were designed and applied for binding streptavidin, promoting affinity biosensing and enzyme activity on gold surfaces of sensors. The synthesis of 1-((+)-biotin)pentanamido)propyl)-3-(12-mercaptododecyl)-imidazolium bromide, a biotinylated ionic liquid (IL-biotin), which self-assembles on gold film, aff...
Article
Full-text available
A competitive binding assay based on localized surface plasmon resonance (LSPR) of folic acid-functionalized gold nanoparticles (FA-AuNPs) and human dihydrofolate reductase enzyme (hDHFR) was developed to detect nanomolar to micromolar concentrations of the widely applied anti-cancer drug, methotrexate (MTX). By the nature of the competitive assay...
Article
The anti-cancer drug, methotrexate (MTX) as a strong inhibitor of human dihydrofolate reductase (hDHFR) has been studied in localized surface plasmon resonance (LSPR) and surface plasmon resonance (SPR) competitive binding assays with folic acid stabilized gold nanoparticles (FA AuNP). The latter with a diameter of 15 nm were prepared in a simple s...
Article
Full-text available
A simple anion metathesis in diluted aqueous carbonate at room temperature affords 1-(12-mercaptododecyl)-3-methyl-imidazolium carbonate (MDMI-HCO(3)) from MDMI salts self-assembled on gold films and nanoparticles. The properties of MDMI-SAM differ from MDMI in solution, for which the anion exchange reaction does not proceed.
Article
Full-text available
A peptide self-assembled monolayer (SAM) was designed to bind His-tagged biomolecules for surface plasmon resonance (SPR) bioanalysis, which was applied for the determination of K(d) for small ligand screening against CD36. Nonspecific adsorption could be minimized using penta- and hexa-peptide monolayers. In particular, monolayers consisting of 3-...

Citations

... Plasmonic devices based on metal nanostructures can concentrate and enhance light in their near surroundings, which may be exploited to increase light-matter interaction in nanoscale spatial regions [1]. This remarkable property has enabled the development of highly sensitive label-free optical biosensors [2,3] based on either the sensitivity of surface plasmon polariton (SPP) and/or localized surface plasmon (LSP) resonances to changes of the refractive index at metal/dielectric interfaces, or Raman signal amplification due to SP electromagnetic field enhancement (surfaceenhanced Raman spectroscopy). These plasmonic biosensing structures typically include metal nanoparticles in colloidal solutions [4][5][6] and periodic arrangements of metal nanostructures on planar substrates [7][8][9][10][11][12]. ...
... Among them, those based on prisms also known as Kretschman's configuration are most commonly used in commercial and research instruments [10]. Recently, portable SPR sensors for point-of-care testing have received increasing attention [11][12][13][14]. Due to the flat geometry and small size of the grating, grating-coupled SPR (GCSPR) sensors are superior to prism-coupled ones in constructing portable devices [15,16]. ...
... The thickness of the diffused electric double-layer, referring to as "Debye length", can also limit these nanoparticles' trajectory. Therefore, a stable dispersion can be formed at a higher repulsion force and longer Debye length among nanoparticles (Bukar et al., 2014;French et al., 2009;Lombardo et al., 2015). The addition of opposite charge ions can compress the thickness of the diffused electric double-layer and reduce the value of Zeta potential at the slipping plane. ...
... Recently, various analytical methods have been reported for MTX determination in biological samples where among them chromatographic assays are more widely reported approaches for MTX detection. Besides, other methods including mass spectrometry (LC-MS/M) [8], electrochemistry [9], fluorescence [10,11], surface plasmon resonance spectroscopy [12], capillary electrophoresis [13], and luminescence [14] are also employed in the literatures. Nevertheless, the performance of each method depends on the limitations associated with their use such as complex operation steps, expensiveness and long analysis time [8]. ...
... The SPR sensors are an important analytical technique for label free and real time analysis of biomolecular interactions. In the last two decades SPR sensing techniques became the most promising candidate for development in medical diagnostics and other sensing devices [6,7]. For generation of surface plasmons novel metals like gold, silver, copper and aluminum are commonly used. ...
... A self-assembled monolayer of an ionic liquid was also applied to gold nanoparticles in order to selectively detect counter-anions 24 or to make a new class of enzymatic biosensors by studying the displacement of the plasmonic band of the IL-functionalized Au nanoparticles. 25 Besides the formation of a self-assembled monolayer using thiol-terminated ILs on noble metal surfaces, IL-SAMs can also be formed on hydroxyl modified surfaces by using alkoxysilanes bearing imidazolium moieties. 26 This process leads to extending the immobilization of ionic liquid moieties to various substrates and nanomaterials (Fig. 2). ...
... 6 Similar to other anti-tumor drugs, MTX also has a problem of a narrow therapeutic window, especially in the renal or liver impaired patients. 7 Occurrence of side effects, including nephrotoxicity, blood toxicity, myelosuppression, and so on, has been observed among patients receiving high-dose MTX (HDMTX). 8,9 In addition, delayed elimination should be focused on for patients with MTX-associated acute kidney injury. ...
... Matrix deposition was performed by successive evaporation of 0.5 lL of matrix solution on the digested spots to analyze proteins and beside the digested spots for lipid analysis. MS analysis of the adsorbed material was performed with a MALDIÀTOF/TOF mass spectrometer (Bruker Daltonics, Bremen, Germany) as previously described (Ratel et al., 2011). ...
... In order to ensure proper distance and the required biorecognition, the surface of metallic nanoparticles should be properly functionalized. Conjugation with emitters typically involves binding via streptavidin-biotin [18,19], His-tag with Ni-NTA [20,21], or virus-antibody [22,23]. Streptavidin-biotin is one of the strongest conjugation pairs, and the conjugation is fast, occurring typically within a few seconds [24,25]. ...