Browsing by Author "Lin, Jia-Yi"

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Multilayer gold nanoparticle-assisted thermal desorption ambient mass spectrometry for the analysis of small organics
(2010)
Lin, Jia-Yi
;
Chen, Tsung-Yi
;
Chen, Jen-Yi
;
Chen, Yu-Chie
;
應用化學系
In this study, thermal desorption-based ambient mass spectrometry (TDAMS) for the analysis of small organics was explored. A layer-by-layer (LBL) self-assembled multilayer of a gold nanoparticle (AuNP)-based glass chip (Glass@AuNPs) with the absorption capacity in the near-infrared (NIR) region was used as the energy absorber and as the sample holder for sample deposition at ambient condition. An NIR laser diode (808 nm) was successfully employed as the thermal desorption source to liberate only small molecules from Glass@AuNPs chips. Followed by post-ionization, the resultant ions were monitored by an ion trap mass spectrometer. Post-ionization was assisted by a spray consisting of 50% deionized water-acetonitrile containing 0.1% acetic acid generated from a short tapered capillary by employing a high voltage (4 kV). Analytes with different polarities including small acids, amino acids, insecticides, and biodiesel samples such as ethyl esters can be directly analyzed using this approach. We demonstrated that this ambient mass spectrometric method was suitable for selectively analyzing small target organics directly from complex samples without any sample pretreatment.
Surface-assisted laser desorption/ionization mass spectrometry on titania nanotube arrays
(2008-07-01)
Lo, Chun-Yuan
;
Lin, Jia-Yi
;
Chen, Wei-Yu
;
Chen, Cheng-Tai
;
Chen, Yu-Chie
Titania nanotube arrays (NTA) generated from anodizing processes are tested as the substrate for surface-assisted laser desorption/ionization mass spectrometry (SALDI MS). The background generated from fitania NTA is very low, making the approach suitable for the analysis of small molecules. The upper detectable mass is similar to 29 kDa. Homogeneous sample deposition leads to good shot-to-shot reproducibility and suitability for quantitative analysis. Additionally, phosphopeptides can be selectively trapped on the fitania NTA substrate, as illustrated by simply depositing a tryptic digest of beta-casein followed by titania NTA SALDI MS analysis. The detection limit for small organics and peptides is in low fmol.
Ultrasonication-Assisted Spray Ionization Mass Spectrometry for the Analysis of Biomolecules in Solution
(2010-09-01)
Chen, Tsung-Yi
;
Lin, Jia-Yi
;
Chen, Jen-Yi
;
Chen, Yu-Chie
;
應用化學系
In this paper, we describe a novel technique-ultrasonication-assisted spray ionization (UASI) for the generation of singly charged and multiply charged gas-phase ions of biomolecules (e.g., amino acids, peptides, and proteins) from solution; this method employs a low-frequency ultrasonicator (ca. 40 kHz) in place of the high electric field required for electrospray ionization. When a capillary inlet is immersed into a sample solution within a vial subjected to ultrasonication, the solution is continually directed to the capillary outlet as a result of ultrasonication-assisted capillary action; an ultrasonic spray of the sample solution is emitted at the outlet of the tapered capillary, leading to the ready generation of gas-phase ions. Using an ion trap mass spectrometer, we found that singly charged amino acid and multiply charged peptides/proteins ions were generated through this single-step operation, which is both straightforward and extremely simple to perform. The setup is uncomplicated: only a low-frequency ultrasonicator and a tapered capillary are required to perform UASI. The mass spectra of the multiply charged peptides and proteins obtained from sample solutions subjected to UASI resemble those observed in ESI mass spectra. (J Am Soc Mass Spectrom 2010, 21, 1547-1553) (C) 2010 American Society for Mass Spectrometry