Search for: All records

Ion mobility spectrometry (IMS) can delineate gas-phase ions and probe their geometries. Coupling with electrospray ionization and MS has brought IMS to structural biology, revealing the macromolecular folding and subunit connectivity. However, the orientational averaging of ion–molecule collision cross sections (Ω) in the linear and field asymmetric waveform IMS (FAIMS) diminishes the resolution and structural specificity. In the novel low-field differential (LOD) IMS, a field too weak for ion heating (and thus FAIMS) aligns strong macrodipoles, capturing their magnitudes and directional Ω across the dipole (Ω⊥). However, the bisinusoidal waveforms (from FAIMS) have compromised the resolution, measurement accuracy, and correlation to the ion properties. Large ions amenable to LODIMS have low mobility and diffuse slowly, allowing the waveform frequencies down to ∼10 kHz. The low field and frequency permit generating the ideal rectangular waveforms with a flexible frequency and duty cycle by direct switching (impractical for FAIMS) in a miniature low-power format. This new IMS stage is evaluated for the exemplary large protein albumin (66 kDa) previously studied using the bisinusoidal waveform. The flat voltages and greater form factor initiate the differential IMS effect at lower fields, expand the separation space, and enable the quantification of Ω⊥ values by varying the duty cycle. 

Whiteface Mountain (WFM) in northern NY State is the site of a historic mountaintop atmospheric observatory with an ongoing cloud water chemistry monitoring program that has been operating every summer (June through September) since 1994. Though long-term chemical analysis has been conducted, no analysis on the microbiome has been completed at WFM. Over the years, a new chemical regime has been reported in the cloudwater with missing analytes. Knowing how microbes can interact with chemicals, we hypothesize microbes are partially responsible for this shift and are crucial in understanding the chemical background of clouds. To start this study, cloudwater filters have been analyzed both chemically and microbially. Chemically, weighted averages have been calculated for each cloudwater filter based on the chemical composition of the clouds. Microbially, we have begun DNA extractions and subsequent metagenomic analysis using the Oxford Nanopore MinION using a select number of cloud water filters from 2024. Overall, this study aims to build upon microbial work accomplished by the Puy de Dôme groups and discuss the collection, storage, and analysis of cloudwater filters to connect the chemical to the microbial at WFM. 

ABSTRACT Ovarian cancer (OvCa) remains the leading cause of gynecological cancer mortality, with most patients developing chemoresistance. Drug repurposing offers promising alternatives, with mebendazole (MBZ) showing anticancer activity. This study evaluates MBZ efficacy using Spectral Domain Optical Coherence Tomography (SD‐OCT). We conducted longitudinal imaging of 40 wild‐type (WT) and cisplatin‐resistant (CPR) OVCAR8 multicellular tumor spheroids over 11 days. Four analyses were performed: volume analysis, optical attenuation analysis, uniformity analysis, and texture feature analysis. Volume analysis showed MBZ reduced spheroid growth in both groups, with greater effects in CPR‐MCTs. Optical attenuation analysis revealed increased necrotic tissue ratios in treated spheroids. Uniformity analysis demonstrated MBZ targets heterogeneous tissues effectively. Texture analysis identified significant structural changes, with 866 altered features in CPR spheroids versus 124 in WT spheroids. Cell viability assays confirmed MBZ's effectiveness against standard and chemo‐resistant OVCAR8 tumors. This study demonstrates SD‐OCT's utility for noninvasive therapy monitoring in 3D cancer models. 

Perovskite-derived hybrid platinum iodides with the general formula A 2 Pt IV I 6 (A = formamidinium FA and guanidinium GUA) accommodate excess I 2 to yield hydrogen-bond-stabilized compounds where the I 2 forms catenates with I − anions on the PtI 6 octahedra.