Mesoporous silica nanocrystals have been developed as sonosensitizers for efficient dynamic therapy of tumors.

For real application, it is an urgent demand to fabricate stable and flexible surface-enhanced Raman scattering (SERS) substrates with high enhancement factors in a large-scale and facile way. Herein, by using the electrospinning technique, a hydrophobic and flexible poly(styrene-co-butadiene) (SB) fibrous membrane is obtained, which is beneficial for modification of silver nanoparticles (Ag NPs) colloid in a small region and then formation of more “hot spots” by drying; the final SERS substrate is designated as Ag/SB. Hydrophobic Ag/SB can efficiently capture heterocyclic molecules into the vicinity of hot spots of Ag NPs. Such Ag/SB films are used to quantitatively detect trace triazophos residue on fruit peels or in the juice, and the limit of detection (LOD) of 2.5 × 10−8 M is achieved. Ag/SB films possess a capability to resist heat. As a case, 6-mercaptopurine (6MP) that just barely dissolves in 90 °C water is picked for conducting Ag/SB-film-based experiments.

Long-term exposure to nicotine causes a variety of human diseases, such as lung damage/adenocarcinoma, nausea and vomiting, headache, incontinence and heart failure. In this work, as a surface-enhanced Raman scattering (SERS) substrate, zinc oxide (ZnO) tips decorated with gold nanoparticles (AuNPs) are fabricated and designated as ZnO/Au. Taking advantage of the synergistic effect of a ZnO semiconductor with morphology of tips and AuNPs, the ZnO/Au-based SERS assay for nicotine demonstrates high sensitivity and the limit of detection 8.9 × 10−12 mol/L is reached, as well as the corresponding linear dynamic detection range of 10−10–10−6 mol/L. Additionally, the signal reproducibility offered by the SERS substrate could realize the reliable determination of trace nicotine in saliva.

The tobacco epidemic is a public health threat that has taken a heavy toll of lives around the globe each year. As one of the poison species from smoking, formaldehyde (FA) affects both the smokers and nearby persons who are exposed to second-hand smoke. Therefore, on-site tracking of FA exposure could evaluate the public environmental safety and mitigate the potential hazards. Herein, we first prepare SiO2-shelled AuAg alloy nanoparticles (AuAg@SiO2) and then embed AuAg@SiO2 within agarose hydrogel to construct the three-dimensional (3D) surface-enhanced Raman scattering (SERS) substrate. A reagent of 3-methyl-2-benzothiazolinone hydrazine (MBTH) with reaction activity toward FA is loaded in the 3D substrate to obtain the selective SERS patch (designated as M-hydrogel patch). Based on a marker Raman peak at 1273 cm–1 from the reaction product of MBTH-FA, the M-hydrogel patch is used to realize SERS detection of FA in smoke. A good linear relationship from 5 × 10–4 to 5 mg/m3 and a limit of detection (LOD) of 2.92 × 10–5 mg/m3 could be reached. While for detection of FA in aqueous, a linear range of 1 × 10–7–1 × 10–3 mg/mL with an LOD of 1.46 × 10–8 mg/mL could be achieved. As the real application, the proposed M-hydrogel patch could be placed anywhere indoor to SERS evaluate the spatial distribution of FA in tobacco smoke, which is in connection with the second-hand smoke effect on children and adults. Such M-hydrogel patch-based SERS assay is exerted for on-field detection of FA in water and furniture panels by using a portable Raman system, showing satisfactory selectivity and reproducibility.