The fabrication of scatheless triangle nanoparticles for biosensor

Triangle nanoparticles used in biosensor are usually fabricated by combining polystyrenes spheres (PSs) self-assembly with metal deposition and a lift-off process. The sharp corners of the triangle are damaged easily in the conventional lift-off process. In this paper, a scatheless triangle nanoparticles fabrication method is presented by using a sticky and soft 184 polydimethylsiloxane (PDMS) membrane to remove the PSs. During the PSs being removed process, the nanoparticles on the sample surface are in isolation and do not contacted with the PDMS because the much smaller height than that of the PSs. Triangle nanoparticles are not any damaged and polluted. Corresponding experiments were performed and triangle particles with sharp corners were obtained. The extinction spectrums were measured using a scanning USB4000-UV–VIS spectrophotometer. The relative height of the extinction peak is about 3.4 times larger than that of the particles fabricated by conventional method. The chip based on the scatheless triangle nanoparticles was used to detect 1 μg/ml staphylococcal enterotoxin B (SEB) and the extinction peak shift value was much larger than that of the chip fabricated using the conventional method.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► An effective scatheless triangle nanoparticles fabrication method was presented. ► The particles are in isolation from the sacrificial layer in lift-off process. ► This method can make the particles extinction peak is 3.4 times higher. ► The detection sensitivity of biosensor chip can be greatly improved.