Mpox Viral Lineage Analysis and Technique Development Using Next-generation Sequencing Approach.

Background: In response to Mpox endemic and public health emergency, DCHHS aimed to develop NGS based techniques to streamline Mpox viral clade and lineage analysis.

Methods: The Mpox sequencing workflow started with DNA extraction and adapted Illumina's COVIDSeq assay using hMpox primer pools from Yale School of Public Health. Sequencing steps included cDNA amplification, tagmentation, PCR indexing, pooling libraries, sequencing on MiSeq, data analysis, and report generation.

Comparison of an ID NOW COVID-19 Assay Used at the Point of Care to Laboratory-Based Nucleic Acid Amplification Tests.

The emergence of a novel coronavirus, namely, SARS-CoV-2, necessitated the use of rapid, accurate diagnostics to quickly diagnose COVID-19. This need has increased with the emergence of new variants and continued waves of COVID-19 cases. The ID NOW COVID-19 assay is a rapid nucleic acid amplification test (NAAT) that is used by hospitals, urgent care facilities, medical clinics, and public health laboratories for rapid molecular SARS-CoV-2 testing at the point of care.

Genuine and counterfeit prescription pill surveillance in Washington, D.C.

For the first time in Washington, D.C., an in-depth analysis of counterfeit pills has been performed as part of a larger initiative to understand the city's illicit drug supply.

Analysis of drug residue in needle-exchange syringes in Washington, D.C.

For the first time in Washington, D.C., an analysis of drug residue from used needle-exchange syringes has been performed.

Photoemission ambient pressure ionization (PAPI) with an ultraviolet light emitting diode and detection of organic compounds.

The development of compact, rugged and low-power ion sources is critical for the further advancement of handheld mass analyzers. Further, there is a need to replace the common (63)Ni source used at atmospheric pressure with a non-radioactive substitute. We present here a description of a light emitting diode (LED) photoemission ionization source for use in mass spectrometry for the detection of volatile organic compounds.

Electrospray photoionization (ESPI) liquid chromatography/mass spectrometry for the simultaneous analysis of cyclodextrin and pharmaceuticals and their binding interactions.

We report on the use of a multimode electrospray ionization/atmospheric pressure photoionization source (ESI/APPI or ESPI for short) with liquid chromatography/mass spectrometry (LC/MS) to measure all components of a mixed-polarity liquid sample containing: (1) low-polarity component (hormone, pharmaceutical or sterol), (2) polar component (cyclodextrin substrate), and (3) bound polar complex. The ESPI source has several advantages over both single ESI and multimode electrospray ionization/chemical ionization (ESCI) analysis, including an enhanced bound-complex detection and better performance at lower solvent flow rates. Relative binding constants are determined with (i) ESI mode, resulting in relative R(ESI-MS) values, and (ii) both ESI and APPI modes, providing relative K(D) values.

Liquid chromatography-atmospheric pressure photoionization-mass spectrometry analysis of triacylglycerol lipids--effects of mobile phases on sensitivity.

In this work, we evaluate the performance of liquid chromatography-atmospheric pressure photoionization-mass spectrometry (LC-APPI-MS) for non-aqueous reversed phase analysis of six triacylglycerol model compounds using six binary mobile phases including MeOH/iPrOH, MeOH/CHCl(3), MeOH/CH(2)Cl(2), CH(3)CN/iPrOH, CH(3)CN/CHCl(3), and CH(3)CN/CH(2)Cl(2). All mobile phases give comparably good separation performance on a Gemini C(18) column with carefully adjusted gradient elution programs. APPI sensitivity varies from one mobile phase to the other without dopants; however use of dopants brings sensitivity to comparable levels for all mobile phases.

Electrospray ionization/atmospheric pressure photoionization multimode source for low-flow liquid chromatography/mass spectrometric analysis.

Analysis of several polar and non-polar compounds is performed with a newly developed dual electrospray ionization/atmospheric pressure photoionization (ESI/APPI) or ESPI source. Several variables are considered in the source, such as ESI probe heater temperature, solvent flow, dopant effects, repeller plate voltage, source geometry and photon energy (Kr vs. Ar lamp).

APPI-MS: effects of mobile phases and VUV lamps on the detection of PAH compounds.

The technique of atmospheric pressure photoionization (APPI) has several advantages over electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI), including efficient ionization of nonpolar or low charge affinity compounds, reduced susceptibility to ion suppression, high sensitivity, and large linear dynamic range. These benefits are greatest at low flow rates (i.e.

Real-time analysis of exhaled breath via resonance-enhanced multiphoton ionization-mass spectrometry with a medium pressure laser ionization source: observed nitric oxide profile.

An elevated concentration of nitric oxide (NO) in alveolar ventilation is indicative of inflammatory stress within the lung. We present here the first description of time-resolved measurement of NO in breath using photoionization mass spectrometry, providing new capabilities for the medical investigator, such as isotopic tracing. Here we use resonance-enhanced multiphoton ionization (REMPI) with time-of-flight mass spectrometry (TOF-MS) coupled with a medium pressure laser ionization (MPLI) source for the selective detection of NO in breath.

Simultaneous measurement of nitric oxide (NO) and nitrogen dioxide (NO2) in simulated automobile exhaust using medium pressure ionization-mass spectrometry.

In previous papers we have demonstrated two different, two-color resonance-enhanced multiphoton ionization (REMPI) schemes for the simultaneous measurement of trace amounts (ppbV to pptV) of nitrogen monoxide (NO) and nitrogen dioxide (NO(2)). The goal of this study is to provide a laser ionization-mass spectrometric scheme capable of measuring ppmV to ppthV concentrations of NO and NO(2) within vehicle exhaust containing up to ppthV of aromatic hydrocarbons and a time frame of seconds. Two ionization schemes are used here to measure NO and NO(2) in simulated automobile exhaust with three different sources.

Selective measurement of HCHO in urine using direct liquid-phase fluorimetric analysis.

Quantification of formaldehyde (HCHO) in urine was recently shown to be a promising tool in the investigation of cancer, particularly bladder cancer. Development of a low-maintenance, inexpensive and rapid analyzer for HCHO in urine would greatly facilitate future research and the potential diagnosis of bladder cancer. We examine here the application of an off-the-shelf system, originally designed for gas-phase atmospheric monitoring of HCHO, for the quantification of HCHO in urine.

Development of medium pressure laser ionization, MPLI. Description of the MPLI ion source.

A novel pulsed valve/ion source combination capable of time-resolved sampling from atmospheric pressure has been developed for use with laser ionization time of flight mass spectrometry. The source allows ionization extremely close to the nozzle of the pulsed valve, enabling ultra-sensitive detection of a number of compounds, e.g.