{'fraction_non_alphanumeric': 0.028455284552845527, 'fraction_numerical': 0.009654471544715448, 'mean_word_length': 5.310897435897436, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Rapid Fabrication of Flexible and Transparent Ag Nanocubes@PDMS Film as SERS Substrate with High Performance.

Flexible and transparent SERS substrates have long been sought-after for non-destructive detection of analytes on non-planar surfaces, but there is still a lack of one convenient and robust way to fabricate such SERS substrates rapidly. Herein, we demonstrate the fabrication of high performance SERS substrate consisting of plasmonic Ag nanocubes (Ag NCs) arrays anchored onto flexible transparent polydimethylsiloxane (PDMS) membrane. Through simple organic/water interfacial self-assembly method, arrays of pre-synthesized Ag NCs are obtained and directly retrieved onto PDMS membrane without the aid of rigid substrates (e.g. Si wafer or glass slide). The plasmonic Ag NCs arrays can produce strong electromagnetic enhancement, achieving high SERS enhancement factor (~ 3.43×106) and ideal detection capability for methylene blue and Rhodamine 6G at respective trace amount of 10-10 M and 10-9 M. Moreover, without the need to transfer from substrate to substrate, the regular Ag NCs arrays are kept intact thereby yielding a good reproducibility (RSD ~12%). We demonstrate further that our as-fabricated SERS substrate displays ideal selectivity towards different kind of analyte molecules (R6G, CV and MB) based on principle component analysis. PDMS membrane owns excellent transparency and flexibility, thus the substrate enables the conformal contact with non-planar surfaces and allows the penetration of laser to reach the analytes from the reverse side of the substrate. This thus facilitates in-situ SERS detection of trace residual crystal violet on fish skin, with LOD reaching 0.6 ppm. This fabrication method reported here is economical and easily-implemented. The robust Ag NCs@PDMS could be readily prepared and stored to meet diverse SERS sensing applications especially for in-situ detection of analytes on irregular non-planar surfaces.