Colorimetric detection of melamine in milk by using gold nanoparticles-based LSPR via optical fibers

Abstract

A biosensing system with optical fibers is proposed for the colorimetric detection of melamine in liquid milk samples by using the localized surface plasmon resonance (LSPR) of unmodified gold nanoparticles (AuNPs). The biosensing system consists of a broadband light source that covers the spectral range from 200 nm to 1700 nm, an optical attenuator, three types of 600 μm premium optical fibers with SMA905 connectors and a miniature spectrometer with a linear charge coupled device (CCD) array. The biosensing system with optical fibers is low-cost, simple and is well-proven for the detection of melamine. Its working principle is based on the color changes of AuNPs solution from wine-red to blue due to the inter-particle coupling effect that causes the shifts of wavelength and absorbance in LSPR band after the to-be-measured melamine samples were added. Under the optimized conditions, the detection response of the LSPR biosensing system was found to be linear in melamine detection in the concentration range from 0μM to 0.9 μM with a correlation coefficient (R2) 0.99 and a detection limit 33 nM. The experimental results obtained from the established LSPR biosensing system in the actual detection of melamine concentration in liquid milk samples show that this technique is highly specific and sensitive and would have a huge application prospects.

Review on Nanomaterial-Based Melamine Detection

“…This method showed a LOD at picogram level, and hence such design is highly desirable. The BSA conjugated Au NPs were Aggregation and electrostatic forces involved tactics were also described by a few reports [122,134,144,154,158]. However, these methodologies still require more attention.…”

Fiber-Optic Localized Surface Plasmon Resonance Sensors Based on Nanomaterials

“…In a preliminary study of the practical applications in food contents analysis, the sugar contents in three different commercial juices were measured ( Figure 13 b), and it was confirmed that the sensor has the potential to be applied to the analysis of ingredients for food or beverages. Chang et al [ 114 ] developed a fiber-optic LSPR colorimetric sensor to detect melamine in milk samples. The fiber-optic melamine sensor was based on the sensitivity improvement by the LSPR derived from unmodified gold nanoparticles.…”

A High-matched Melamine Sensor Using Core/shell Nano Particles of Fe3O4@Polyrutin–COOH and Ionic Liquid as Imprinted Polymeric Monomers

“…Various analytical methods have been used in the determination of MEL in dairy products such as high performance liquid chromatography (HPLC)-UV detection (HPLC-UV) [26][27][28] or -tandem mass spectrometry (LC-MS/MS) [29][30][31] . And the hydrophilic interaction liquid chromatography (HILIC) 32 , surface-enhanced Raman spectroscopy (SERS) 33 and surface plasmon resonance (SPR) 34 suspension with the protection of N 2 flow and stirred for min. Then the core/shell nano particle of Fe O 4 @Polyrutine-COOH was accepted easily with an external magnetic field.…”