Precious metal nanoparticle composite SERS fiber and preparation method and application thereof

Abstract

The invention discloses a precious metal nanoparticle composite SERS fiber and a preparation method and application thereof, and relates to the field of flexible SERS substrate materials. The preparation method of the composite SERS fiber comprises the following steps that S1, precious metal nanoparticle sol is prepared by adopting a sodium citrate reduction method and taking a sodium citrate solution as a reducing agent; S2, the noble metal nanoparticle sol is concentrated for direct use or the concentrated noble metal nanoparticle sol is modified with probe molecules; S3, the concentrated noble metal nanoparticle sol or the modified noble metal nanoparticle sol obtained in the step 2 is mixed with alginate, stirred and defoamed to obtain a spinning solution; and S4, the spinning solutionobtained in the step 3 is sucked into an injector, the spinning solution is extruded into a coagulating bath by a metering pump through a spinning nozzle to form a fiber precursor, and the fiber precursor is drawed, washed and dried. The fiber prepared by the preparation method can be combined with a handheld portable Raman spectrometer for on-site rapid detection, and can also be applied to pH sensing, biosensing, body fluid acidity and alkalinity and detection of small molecular substances in body fluid.

Description

technical field [0001] The invention belongs to the technical field of functional composite materials, and in particular relates to a flexible SERS fiber. More specifically, the invention relates to a precious metal nanoparticle composite SERS fiber and its preparation method and application. Background technique [0002] SERS technology has attracted much attention because it can greatly enhance the Raman scattering signal to obtain molecular vibration and rotation spectrum information. The use of SERS technology can detect analytes quickly and non-destructively, and has high selectivity and sensitivity. The SERS substrate activity plays a crucial role in the influence of the SERS effect. Therefore, the preparation of efficient, convenient and excellent SERS substrates has always been a research hotspot in this field. [0003] At present, there are three types of common SERS substrates: one is precious metal sol SERS substrates, commonly used are gold sol and silver sol; ...

AI Technical Summary

Problems solved by technology

However, the above three types of SERS substrates all have defects: the preparation of precious metal sol SERS substrates is traditionally simple and easy to implement, but the substrate is unstable in solution state, prone to aggregation and precipitation, which is inconvenient to store, and it is difficult to detect the target object in aqueous solution, and cannot be recycled after use. waste of raw materials

The rigid material composite SERS substrate has good stability, but it is easy to be damaged and not easy to carry. Most of the preparation methods are cumbersome and complicated, and require relatively high equipment requirements, making it difficult to produce on a large scale.

As a flexible material composite substrate, SERS fiber is low in cost, stable and portable, has good mechanical resistance, and can be attached to any complex surface target for rapid identification and analysis. The preparation of SERS fiber substrates currently reported includes SERS cotton cloth, silk, paper, etc. etc., it does not have weaving characteristics, and the application occasions are limited, especially for relatively expensive biological targets, the unique water absorption characteristics of macro-block fibers lead to a larger sample size and higher testing costs

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