Glass/PDMS hybrid microfluidic device integrating vertically aligned SWCNTs to ultrasensitive electrochemical determinations

Abstract

This communication reports a promising platform for rapid, simple, direct, and ultrasensitive determination of serotonin. The method is related to integration of vertically aligned singlewalled carbon nanotubes (SWCNTs) in electrochemical microfluidic devices. The required microfabrication protocol is simple and fast. In addition, the nanomaterial influenced remarkably the obtained limit-of-detection (LOD) values. Our system achieved a LOD of 0.2 nmol L 21 for serotonin, to the best of our knowledge one of the lowest values reported in the literature.Glass/elastomer hybrid microfluidic platforms with integrated electrochemical detectors are powerful analytical tools. Their main advantages include: (i) low cost; (ii) chemical inertia; (iii) optical transparency; (iv) thermal, mechanical, and chemical stability; (v) automation capacity, and; (vi) easy microfabrication. In addition, they offer high values of reproducibility and sensitivity.

Self-regenerating and hybrid irreversible/reversible PDMS microfluidic devices

“…However, the harsh plasma conditions damage surface-anchored groups such as receptors for chemical sensors. This phenomenon avoids surface modifications before bonding 33 . The inert and hydrophobic nature of PDMS hinders in situ modification processes, especially when patterned and small structures are required 34 .…”

Carbon nanotubes in microfluidic lab-on-a-chip technology: current trends and future perspectives

“…Functionalized CNTs have been reported in micro-fluidic LOC devices. In these studies, the high surface area of CNTs has been covalently or non-covalently functionalized with biomolecules such as antibodies (Venkatanarayanan et al 2012; Kadimisetty et al 2015; Rasooly et al 2013), enzymes (Ali et al 2013), proteins (Ali et al 2015), aptamers (He et al 2013), and single-stranded DNA molecules (Moraes et al 2012), or alternatively with non-biological polymers (Ge et al 2013), and transition-metal hexacyanoferrates (TMHCFs) such as cobalt-hexacyanoferrate (Li et al 2012b). As examples of covalent and non-covalent functionalization, one report concerning covalent and non-covalent functionalization is described in detail.…”

Development of a nanostructured electrochemical immunosensor applied to the early detection of invasive aspergillosis

“…procedure proposed byMoraes et al (2012) with own modifications[17]. The microfluidic immunosensor design consisted of a T-type format with a central channel (CC) (60 mm length; 100 µm diameter) and accessory channels (15 mm length; 70 µm diameter).…”