A Desalting Approach for MALDI-MS Using On-Probe Hydrophobic Self-Assembled Monolayers

Brockman, Adam; Dodd, Brian S.; Orlando, Ron

doi:10.1021/ac970650u

Cited by 83 publications

(75 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sequence of bradykinin (1-7) contains a phenylalanine (F), whereas C-telopeptide does not. After incubation (with the two peptides) and extraction using the AuNP capped b-cyclodextrin, the captured analyte (bradykinin [1][2][3][4][5][6][7]) was ionized without the use of an organic matrix. Figure 3 (blue spectrum) contains the data from a selective analyte capture and ionization experiment using b-cyclodextrin capped AuNPs.…”

Section: Selective Analyte Capture and Ionization With Selfassembled mentioning

confidence: 99%

Nanoparticles for Selective Laser Desorption/Ionization in Mass Spectrometry

Castellana

Sherrod

Russell

2008

JALA: Journal of the Association for Laboratory Automation

View full text Add to dashboard Cite

T he selective desorption/ionization of analytes using nanomaterials is investigated using metallic nanoparticles. By replacing the sodium citrate capping of gold nanoparticles with self-assembled monolayers, we are able to both enhance analyte ionization and selectively capture analytes. Capping gold nanoparticles with a monolayer of 4-mercaptobenzoic acid enhances analyte ionization while greatly decreasing chemical noise resulting from alkali adducted species. Selective capture and sequential desorption/ionization of the peptide bradykinin (1-7) from a two peptide mixture is achieved using b-cyclodextrin capped gold nanoparticles. Finally, by switching from gold to silver nanoparticles, we are able to ionize both folic acid and amphotericin B. These results demonstrate that through careful control of nanoparticle surface chemistry and composition one can achieve selective analyte ionization for MS applications.

show abstract

Section: Selective Analyte Capture and Ionization With Selfassembled mentioning

confidence: 99%

Nanoparticles for Selective Laser Desorption/Ionization in Mass Spectrometry

Castellana

Sherrod

Russell

2008

JALA: Journal of the Association for Laboratory Automation

View full text Add to dashboard Cite

show abstract

“…The target surface was derivatized for the selective retention of analyte while removing interferences through on-target washing. Several surface derivatizations have been designed to extract and concentrate the analyte through hydrophobic interaction [10,11], ionic interaction [12,13], or immunoaffinity [14,15]. However, the sensitivity improvement was limited by the number of binding sites on the target.…”

mentioning

confidence: 99%

Analysis of peptides and proteins affinity-bound to iron oxide nanoparticles by MALDI MS

Chang

Zheng

Chen

et al. 2007

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

Iron oxide nanoparticles modified with oleate have been employed for the extraction of peptides and proteins from aqueous solution before matrix-assisted laser desorption/ionization (MALDI) mass spectrometric (MS) analysis. Adsorption of peptides and proteins onto the nanoparticles were mainly through electrostatic attraction and hydrophobic interaction. The analyte-adsorbed iron oxide nanoparticles could be efficiently collected from solution using a magnet. No elution step was needed. With this preconcentration strategy, the lowest detectable concentration of angiotensin I, insulin, and myoglobin in 500 L of aqueous solution were 0.1 nM, 0.1 nM, and 10.0 nM, respectively. In addition, the nanoparticles could extract the analytes from solution with a high content of salt and surfactant, thus eliminating suppression effect during MALDI MS analysis. This method was successfully applied to concentrate the tryptic digest products of cytochrome c. In addition, the tryptic digestion of cytochrome c can be directly conducted on the iron oxide nanoparticles. atrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) has become a routine analytical tool to determine the molecular mass of biomolecules [1][2][3]. However, samples containing excessive amounts of salts, surfactants, or other contaminations suffer from ionization suppression and adduct formation [4,5]. This limits the application of MALDI technique. Therefore, a simple and selective procedure for extraction and concentration of analyte from complex samples before MALDI MS is required.Various methods have been developed to isolate the analyte from complex sample matrix. In surface-enhanced laser desorption/ionization (SELDI), the sample target played an active role in the extraction, purification, or concentration of the analyte of interest [6 -9]. The target surface was derivatized for the selective retention of analyte while removing interferences through on-target washing. Several surface derivatizations have been designed to extract and concentrate the analyte through hydrophobic interaction [10,11], ionic interaction [12,13], or immunoaffinity [14,15]. However, the sensitivity improvement was limited by the number of binding sites on the target. In another approach, the so-called surface-enhanced affinity capture (SEAC), micrometer-sized beads made for chromatography column were used to capture peptides and proteins from sample solution [16]. Various types of beads have been used, which include reverse-phase chromatographic beads [17,18] and immobilized metal ion beads [19 -21]. To speed up the collection of analyteadsorbed beads from sample solution, magnetic particles, which can be simply collected using a magnet, were developed [22][23][24]. After collection, the microbeads were washed and placed on sample target, followed by analyzing with MALDI MS. Unfortunately, the presence of those particles on the sample target was reported to cause decrease in mass accuracy and resolution [25,26].Recently, nanoparticles have become interesting p...

show abstract

“…MALDI mass spectrometry, in recent times, has proven to be an authentic technique to analyze peptides and proteins [3,4]. These biomolecules out of the complex biofluids like serum are difficult to ionize and thus, bring into time of flight (TOF) because of the complexity of the sample and the suppressing nonvolatile salts [5]. The aforementioned problems are tackled by another technique introduced years ago, namely, surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF MS), for the detection of several peptides and proteins from complex biological specimens [6 -8].…”

mentioning

confidence: 99%

Material-enhanced laser desorption/ionization (MELDI)—A new protein profiling tool utilizing specific carrier materials for time of flight mass spectrometric analysis

Feuerstein

Najam‐ul‐Haq

Rainer

et al. 2006

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

Over the past couple of years, proteomics pattern analysis has emerged as an effective method for the early diagnosis of diseases such as ovarian, breast, or prostate cancer, without identification of single biomarkers. MALDI-TOF MS, for example, offers a simple approach for fast and reliable protein profiling, especially by using carrier materials with various physical and chemical properties, in combination with a MALDI matrix. This approach is referred to as materialenhanced laser desorption/ionization (MELDI). In this paper, we report the development and application of derivatized carrier materials [cellulose, silica, poly(glycidyl methacrylate/divinylbenzene) (GMA/DVB) particles, and diamond powder] for fast and direct MALDI-TOF MS protein profiling. The applicability of MELDI for rapid protein profiling was evaluated with human serum samples. These carriers, having various hydrophobicities, resulted in characteristic mass fingerprints, even if all materials were derivatized with iminodiacetic acid (IDA) to yield an immobilized metal affinity chromatography (IMAC) functionality. Our study demonstrates that analyzing complex biological samples, such as human serum, by employing different MELDI carrier materials yielded type-and size-dependent performance variation. T he quest to diagnose and identify diseases at early stages depends mainly on the accurate determination of the marker entities in the biological fluids. These marker entities are normally very low concentrated [1], and highly sensitive methods are required to bind them effectively from the biosamples and to measure them with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) [2]. MALDI mass spectrometry, in recent times, has proven to be an authentic technique to analyze peptides and proteins [3,4]. These biomolecules out of the complex biofluids like serum are difficult to ionize and thus, bring into time of flight (TOF) because of the complexity of the sample and the suppressing nonvolatile salts [5]. The aforementioned problems are tackled by another technique introduced years ago, namely, surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF MS), for the detection of several peptides and proteins from complex biological specimens [6 -8]. This affinity-based method utilizes selective adsorption of proteins on various chromatographic surfaces to reduce sample complexity [9,10]. Spectra generated by SELDI-TOF MS usually show limited peak and binding capacity due to the smaller surface area of the plane protein chip [11]. Limitations of SELDI are also associated with the lower mass resolution of the applied MS instrument that

show abstract

A Desalting Approach for MALDI-MS Using On-Probe Hydrophobic Self-Assembled Monolayers

Cited by 83 publications

References 20 publications

Nanoparticles for Selective Laser Desorption/Ionization in Mass Spectrometry

Nanoparticles for Selective Laser Desorption/Ionization in Mass Spectrometry

Analysis of peptides and proteins affinity-bound to iron oxide nanoparticles by MALDI MS

Material-enhanced laser desorption/ionization (MELDI)—A new protein profiling tool utilizing specific carrier materials for time of flight mass spectrometric analysis

Contact Info

Product

Resources

About