Publications by authors named "Samantha Douman"

Background: Emtricitabine (FTC) is a commonly prescribed anti-human immunodeficiency virus (HIV) drug that has been classified as an emerging environmental pharmaceutical micropollutant due to its poor metabolism, refractory nature to wastewater treatment, continuous discharge with wastewater effluent and accumulation in the aquatic environment. Although there are no reported limits and toxicity of the drug in the environment yet, it is crucial to develop onsite, rapid, selective and ultrasensitive water sensing systems for FTC to ensure efficient risk management and environmental sustainability.

Results: Herein, a molecularly imprinted poly(para-aminobenzoic acid) (MIP) was electrochemically prepared on iron oxide nanoparticles modified glassy carbon electrode (MIP/FeO NPs/GCE) for selective detection of FTC using differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS).

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There has been increasing interest in the use of biosensors for diagnosis of infectious diseases such as tuberculosis (TB) due to their simplicity, affordability, and potential for point-of-care application. The incorporation of aptamer molecules and nanomaterials in biosensor fabrication explores the advantages of high-binding affinity and low immunogenicity of aptamers as well as the high surface-to-volume ratio of nanomaterials, for increased aptasensor performance. In this work, we employed a novel microwave-synthesized copper indium tin sulfide (CITS) substituted-kesterite nanomaterial, together with a natural biopolymer (chitosan), for signal amplification and increased loading of aptamer molecules.

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Breast cancer (BC) is one of the most common types of cancer disease worldwide and it accounts for thousands of deaths annually. Lapatinib is among the preferred drugs for the treatment of breast cancer. Possible drug toxicity effects of lapatinib can be controlled by real-time determination of the appropriate dose for a patient at the point of care.

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The high incidence of tuberculosis (TB) infection is of great concern world-wide. The traditional TB diagnostic techniques are not ideal for TB diagnosis in resource-poor countries. This is due to their high complexity, expensive nature, long time duration, poor sensitivity and specificity, as well as their requirement for sophisticated laboratories with special biosafety conditions.

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This study is a first-time report of the development of a mercaptosuccinic acid-nickel selenide quantum dots (MSA-NiSe QDs)-based electrochemical aptasensor for brain natriuretic peptide (BNP) detection. Herein, novel MSA-NiSe QDs were synthesized by microwave irradiation. Microscopic and structural analysis revealed that the QDs are spherical with an average diameter of 2 nm.

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The fabrication and electrochemical properties of a 3D printed titanium electrode array are described. The array comprises 25 round cylinders (0.015 cm radius, 0.

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Wireless electrochemiluminescence is generated using interdigitated, 3D printed, titanium arrays as feeder electrodes to shape the electric field. Gold microparticles (45 μm diameter), functionalised with 11-mercaptoundecanoic acid, act as micro-emitters to generate electrochemiluminescence from [Ru(bpy)3]2+, (bpy is 2,2'-bipyridine) where the co-reactant is tripropylamine. The oxide coated titanium allows intense electric fields, whose distribution depends on the geometry of the array, to be created in the absence of deliberately added electrolyte.

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Thin films of a composite of nafion and carbon microparticles have been deposited on nonconducting substrates and their conductivity as well as their ability to generate electrochemiluminescence investigated. The films exhibit very low conductivity (<6 × 10 S m) for low particle loadings, but once the percolation threshold is reached (volume percentage of 71 ± 8% carbon particles), the conductivity increases dramatically and a maximum conductivity of 2.0 ± 0.

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An impedimetric immunosensor for fumonisin B₁ (FB₁) was developed from a poly(2,5-dimethoxyaniline)-multi-walled carbon nanotube (PDMA-MWCNT) composite on the surface of glassy carbon electrode (GCE). The composite was prepared electrochemically and characterized using cyclic voltammetry. The preparation of the FB₁ immunosensor involved the drop-coating of a bovine serum albumin mixture of the anti-fumonisin antibody (anti-Fms) onto the composite polymer-modified GCE.

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