Plasmonic nanoshells enhanced laser desorption/ionization mass spectrometry for detection of serum metabolites

Plasmonic silver nanoshells for drug and metabolite detection

“…Matrix-assisted laser desorption/ionization (MALDI) MS has displayed great superiority considering its fast analysis of analytes in seconds, accurate mass measurement for identification, simple sample preparation for broad application, and high sensitivity with low costs for practical use 1,2,5 . Inorganic particles (e.g., silicon 10,11 , carbon 12,13 , metal [14][15][16] , and metal oxide 17,18 ) have been preferred matrices in LDI MS for small metabolites as reported by research groups globally including ours. These particles can control the analytical variations and background signals in the mass region below m/z of 500, achieving the qualitative analysis of small metabolites, such as carbohydrates and amino acids 6,7,19 .…”

“…4b for three batches of silver nanoshells in parallel. Notably, the absorption band of silver is close to 355 nm (the wavelength for Nd:YAG laser used for LDI MS), beneficial for matrix use compared with gold nanoparticles 16,23,40 . The light absorbance increased and the plasmon resonance peak became broader with higher loading ratio of silver, agreed to TEM, SEM, DLS, and EDX characterizations demonstrating the adjustable properties of silver nanoshells through multi-cycled silver mirror reactions.…”

“…The UV-Vis spectra of particles were checked and the qualified particles would show the absorption peak at~436 nm without red shift (suggesting no overloading of silver). Gold nanoparticles were synthesized using the in-solution seeding approach 16 . The seeding solution was firstly prepared by vigorous mixing of 10 mL of aqueous CTAC solution (0.1 M) and 515 mL of HAuCl 4 (4.86 mM) with 450 mL of NaBH 4 solution.…”

“…Despite that there have been many reports on the application of plasmonic particles for LDI MS 6,7,14,15,19 , most of current work are focused on the use of solid plasmonic particles in diverse shapes and there are very few reports on plasmonic nanoshells. Plasmonic Au nanoshells with nanoscaled surface roughness and higher hot carriers production over solid Au particles 16,22 have been demonstrated to be better candidates for LDI MS detection of small metabolites, whereas their application is very limited in complex bio-fluids for diagnostic purpose 23 . Notably, the analytical performance of plasmonic nanoshells depends on the selection of noble metals to adsorb ultraviolet (UV) laser and optimized shell structure for LDI MS detection.…”

TiO2 Nanocoral Structures as Versatile Substrates for Surface‐Assisted Laser Desorption/Ionization Mass Spectrometry

“…Various molecules such as peptides, drugs, carbohydrates, glycolipids, natural products, and polymers were successfully analyzed with excellent sensitivities using this type of substrate . Due to the success of DIOS substrates, the application of SALDI‐MS was investigated using various nano/micromaterials as substrates, including carbon and silicon‐based materials, metal nanoparticles, metal‐based nanomaterials with unique structures, and other inorganic materials . Among metal oxides, TiO 2 shows potential as a SALDI‐MS substrate.…”