#PURE SILVER AIRCRAFT INKLET PORTABLE#

Recent years have witnessed a growing interest in the application of SERS-based paper substrates for sensing trace chemicals and bioanalysis. Paper substrates have also been successfully applied to fabricate inexpensive SERS substrates and have achieved a good enhancement factor (EF) in the range 10 5–10 7. Although one of the most studied fields of paper is microfluidic paper-based analytical devices (μPADs), paper substrates can be used in other applications for point-of-care medical diagnostics, such as paper-based electrochemical detection, and μPADs can be used for microchip electrophoresis. In recent years, the development of flexible sensing devices fabricated from paper has featured in many research studies because of the unique set of advantages of a paper substrate such as its flexibility, mechanical benefits (easy to cut or shape), low cost, and recyclability. Thus far, PNPs with various shapes have been synthesized and successfully applied in SERS, including nanorods, nanocubes, nanoplates, nanostars, and nanowires. Therefore, efforts were focused on tuning the localized surface plasmon resonance (LSPR) property of plasmonic nanoparticles (PNPs) by improving their assembly and by optimizing their size and shape. Compared to the chemical enhancement, the electromagnetic effect from the excitation of localized surface plasmons (LSPs) near a nanoplasmonic surface accounts for most of the SERS enhancement. The SERS effect is attributed to two mechanisms, namely chemical and electromagnetic.

#PURE SILVER AIRCRAFT INKLET PORTABLE#

Another advantage of a sensing approach based on SERS is that it does not require any sample preparation steps thus, the combination of a SERS substrate with a portable Raman spectrometer constitutes a potentially attractive point-of-care test (POCT) platform. In addition, SERS can be used for multiplex detection owing to its high spatial resolution and the use of single wavelength excitation. SERS enhances the rich chemical fingerprint information provided by Raman spectroscopy via plasmon-enhanced excitation and scattering. Among these technologies, surface-enhanced Raman scattering (SERS) has gained a huge amount of attention because of its ability to detect adsorbed molecules of sub-picomolar concentrations.

These platforms enable miniaturization and enhanced sensitivity, allow rapid analysis, and are able to accommodate low sample volumes. Over the last decades, platforms based on nanomaterials and optical measurement techniques, including fluorescence, surface plasmon resonance (SPR), and colorimetry, have revolutionized conventional laboratory sensing and diagnostic methods. Finally, the batch-to-batch reproducibility and long-term stability of the SERS substrate under ambient conditions make this substrate a good candidate for point-of-care test applications. Moreover, our paper-based SERS substrate has an excellent enhancement factor (EF) of 7.4 × 10 8, which is difficult to achieve on a paper substrate because of the microporous nature of paper. The novel paper-based SERS substrate showed outstanding sensitivity and spot-to-spot reproducibility for on-site detection using a portable Raman spectrometer with a limit of detection (LOD) of 10.7 pM. Pre-modification of the paper with chitosan allowed the formation of randomly oriented nano-wrinkles on the surface, thus enabling the formation of silver nanoparticles with good hotspots. Silver nanoparticles were synthesized directly in the head nozzles of the inkjet printer via the reduction of silver nitrate (AgNO 3) by ascorbic acid. The approach entails the use of an inkjet microreactor for the deposition of silver nanoparticles on the surface of office paper decorated with chitosan nano-wrinkles for the preparation of a reproducible and sensitive paper-based surface-enhanced Raman scattering (SERS) substrate. Here we report a synthesis approach that is simple, surfactant free, and green, and which is additionally cost effective in terms of its material requirements.

Pure silver aircraft inklet