Improvement of corrosion protection offered to galvanized steel by incorporation of lanthanide modified nanoclays in silane layer

peer reviewe

Lanthanide modified nanoclays as reservoirs for doping silane sol-gel layers applied on galvanized steel

peer reviewed

Sensitivity-enhanced localized surface plasmon resonance biosensing format dedicated for point-of-care testing tools

peer reviewedThe main requirement for a point-of-care health monitoring tools is that it should involve relatively simple and inexpensive equipment ensuring acceptable accuracy of diseases early diagnostic. Quite commonly in practice, their main function is only to trigger an ‘alarm’ signal, when a specific biomarker of disease is detected in the sample. The affinity label-free biosensing involving surface plasmonic resonance (SPR) phenomena appears to be one of the most appropriate approaches for the above requirements. In our research, we focus on theoretical and experimental investigations of optional plasmonic-related biosensing formats easy to be integrated in lab-on-chip devices involving conventional planar SPR biosensing. One of such detection formats, mentioned in our earliest publications, involves localized surface plasmon resonance (LSPR) spectroscopy at the frustrated total internal reflection conditions (LSPR_TIR). In this paper, we report on the numerical and experimental study of LSPR_TIR spectroscopy of gold nanoparticles (NPs) structures with a relatively high density of NPs, manufactured using two different microfabrication methods: the conventional nano-sphere lithography, and the original one, involving the direct pulse laser writing. The last technology, developed by our research team, provides powerful and cost effective tools for flexible patterning of the disposable multichannel biochip with array of SPR and LSPR probes. The obtained results demonstrate a significant improvement in the LSPR wavelength sensitivity to sample refractive index. In addition, experimental investigations reveal a relatively efficient conversion of the incident light wave polarization that can be attributed to a relatively high efficiency of electromagnetic coupling between closely spaced NPs.BIOSEN

Compact multichannel spectroscopic label-free biosensor platform for plant diseases Point-Of-Care Testing (POCT)

The POCT technology involving low cost Lab-On-Chip label-free biosensing opens up an opportunity to drastically reduce the total cost of plant health and disease monitoring tools. The main requirement for a POCT tool is that it should involve relatively inexpensive equipment ensuring a sufficiently high accuracy of the plant disease early diagnostic. The principal objective of the presented work was to develop of a cost effective tool for biosensing assay, easy to use even for unskilled user. The label-free biosensing involving an optical near-field resonance phenomenon, such as Surface Plasmon Resonance (SPR) or localized surface plasmon resonance (LSPR), appears to be an appropriate approach for the above requirements. In this paper, we present a concept of multichannel biosensing platform dedicated to POCT, as well as the first proof-of-concept experimental investigations, demonstrating its practical feasibility. The instrumental platform investigated by our research group includes both disposable multichannel biochip and spectroscopic optical readout device. The proposed approach gives access to two plasmonic detection formats on the same lab-on-chip device: SPR and LSPR biosensing. In order to implement the LSPR sensing approach, our team has developed an original microfabrication method involving gold nanoparticles (Au_NPs) synthesis by pulsed laser writing. The biochip includes both microfluidic and biosensor structures formed into a single plastic slab.BIOSEN