Superhydrophobic SERS chip based on a Ag coated natural taro-leaf

Abstract

Surface-enhanced Raman spectroscopy (SERS) substrates based on plasmonic nanostructures allow for label-free and fingerprinting molecular detection with ultrahigh sensitivity and selectivity, but their complicated and high-cost fabrication remains a challenge for practical applications and commercialization of SERS technology. Herein, we developed a facile and low-cost natural SERS substrate based on silver coated taro leaf (Taro-leaf@Ag) that exhibits ordered micro-papillae and secondary crossed nanoplates. The micro-papillae exhibited superior superhydrophobicity for analyte enrichment and the secondary crossed nanoplates provided rich SERS hot spots, which together lead to highly sensitive SERS detection with a detection limit as low as 10(-8) M. Moreover, the crossed nanoplates were uniformly distributed such that reproducible SERS measurements with a 9.7% variation over 1274 spectra was achieved. The high SERS sensitivity and reproducibility as well as the facile and low-cost fabrication make the Taro-leaf@Ag a promising natural SERS substrate for future practical biochemical detection methods.

Tunable laser interference lithography preparation of plasmonic nanoparticle arrays tailored for SERS

“…rose petal, taro leaf and lotus leaf ) were coated with metal and demonstrated to serve as low-cost SERS-active substrates with superhydrophobic properties enabling efficient enrichment of chemical and biological species to specific areas probed with intense electromagnetic field intensity. 22,23 Laser interference lithography (LIL) represents an alternative method that is suitable for the preparation of periodic nanoscale features with controlled size and shape. [24][25][26] LIL techniques offer the advantage of mass production-compatible preparation 27,28 and represent an attractive means for (arguably) the simple and fast patterning of large areas of up to hundreds of square centimeters.…”

Bionic SERS chip with super-hydrophobic and plasmonic micro/nano dual structure

“…Recently, the biological materials with micro/nano structures from the natural world have been used as one type of emerging SERS chip because of simple processes and low costs [1,[13][14][15][16] . These biological surfaces have an innate hierarchical structure composed of micro/nano structures, which do not only provide rich plasmonic hot spots but also exhibit super-hydrophobicity for analyte enrichment.…”

“…In this work, inspired by the taro-leaf hierarchical structure [16], we fabricate a large-area bionic or pseudo-bionic SERS chip with a micro/nano dual structure by a simple and low-cost method. Such artificial SERS chip is demonstrated to have unique super-hydrophobicity and rich plasmonic hot spots, exhibiting an order of magnitude higher sensitivity (∼10 −9 M) and enhancement factor (∼10 7 ) of Raman signals than natural taro-leaf SERS chips.…”

Hierarchical Ag nanostructures on Sn-doped indium oxide nano-branches: super-hydrophobic surface for surface-enhanced Raman scattering

“…One of the best breakthrough to overcome this limitation is the super-hydrophobic surfaced SERS substrate. [15][16][17][18][19][20] Super-hydrophobic surface can reduce the contact area between the surface and the analyte solutions by about 4 to 9 times comparing to the usual hydrophilic substrate.…”