Entries by Katy

Determination of Optimal Electrospray Parameters for Lipidomics in Infrared-Matrix-Assisted Laser Desorption Electrospray Ionization Mass Spectrometry Imaging

Infrared matrix-assisted laser desorption ionization (IR-MALDESI) is an ambient mass spectrometry imaging (MSI) technique that relies on electrospray ionization (ESI) for ion generation of desorbed neutrals. Although many mechanisms in IR-MALDESI have been studied in depth, there has not yet been a comprehensive study of how the ESI parameters change the profiles of tissue specific […]

Clusters tagged by alkali metals

Water clusters and mixed formic acid-water clusters produced in molecular beam have been tagged by one sodium atom and investigated by mass spectrometry and tunable UV laser photoionization. Two series of clusters Na-(H2O)n and Na-(HCOOH)(H2O)n have been detected at various photon energies, from their appearance threshold in the mass spectrum up to 0.5 eV above. The appearance […]

Investigations of β-carotene radical cation formation in infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI)

Radical cationization of endogenous hydrocarbons in cherry tomatoes was previously reported using infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI), a mass spectrometry imaging technique that operates at ambient conditions and requires no sample derivatization. Due to the surprising nature of this odd-electron ionization, subsequent experiments were performed on β-carotene to determine the amount of radical […]

Quantitative Imaging Analysis of the Spatial Relationship between Antiretrovirals, Reverse Transcriptase Simian-Human Immunodeficiency Virus RNA, and Collagen in the Mesenteric Lymph Nodes of Nonhuman Primates

Human immunodeficiency virus (HIV) persistence in tissue reservoirs is a major barrier to HIV cure. While antiretrovirals (ARVs) suppress viral replication, antiretroviral therapy (ART) interruption results in rapid rebound viremia that may originate from lymphoid tissues. To understand the relationship between anatomic distribution of ARV exposure and viral expression in lymph nodes, we performed mass […]

Optical Microscopy-Guided Laser Ablation Electrospray Ionization Ion Mobility Mass Spectrometry: Ambient Single Cell Metabolomics with Increased Confidence in Molecular Identification

Single cell analysis is a field of increasing interest as new tools are continually being developed to understand intercellular differences within large cell populations. Laser-ablation electrospray ionization mass spectrometry (LAESI-MS) is an emerging technique for single cell metabolomics. Over the years, it has been validated that this ionization technique is advantageous for probing the molecular […]

Sarcoma Molecular Pathological Diagnosis of FFPE Tissues without Dewaxing based on Lipidomic Proles using SpiderMass Technology

Background :Formalin-xation and paran-embedding (FFPE) is the worldwide gold standard for tissue preservation and routine pathology for general and cancer diagnostics. Despite robust histopathology methods, accurate diagnostic remains dicult for certain cases. Overall, the entire process is timeconsuming, labor-intensive and doesn’t reach the right sensitivity and specicity. Lipids are central players in cancer, but they […]

Ultraselective Carbon Nanotubes for Photoacoustic Imaging of Inflamed Atherosclerotic Plaques

Disruption of vulnerable atherosclerotic plaques often leads to myocardial infarction and stroke, the leading causes of morbidity and mortality in the United States. A diagnostic method that detects early-stage high-risk atherosclerotic plaques could prevent these sequelae. The abundant immune cells in the arterial wall, especially inflammatory Ly-6Chi monocytes and foamy macrophages, are indicative of plaque inflammation, […]

An excitation-reception collinear probe for ultrasonic, photoacoustic, and thermoacoustic tri-modal volumetric imaging

Imaging systems that integrate multiple modalities can reveal complementary anatomic and functional information as they exploit different contrast mechanisms, which have shown great application potential and advantages in preclinical studies. A portable and easy-to-use imaging probe will be more conducive to transfer to clinical practice. Here, we present a tri-modal ultrasonic (US), photoacoustic (PA), and […]