One-Step Facile Synthesis of Highly Magnetic and Surface Functionalized Iron Oxide Nanorods for Biomarker-Targeted Applications

We report a one-step method for facile and sustainable synthesis of magnetic iron oxide nanorods (or IONRs) with mean lengths ranging from 25 to 50 nm and mean diameters ranging from 5 to 8 nm. The prepared IONRs are highly stable in aqueous media and can be surface functionalized for biomarker-targeted applications. This synthetic strategy involves the reaction of iron­(III) acetylacetonate with polyethyleneimine in the presence of oleylamine and phenyl ether, followed by thermal decomposition. Importantly, the length and diameter as well as the aspect ratio of the prepared IONRs can be controlled by modulating the reaction parameters. We show that the resultant IONRs exhibit stronger magnetic properties compared to those of the widely used spherical iron oxide nanoparticles (IONPs) at the same iron content. The increased magnetic properties are dependent on the aspect ratio, with the magnetic saturation gradually increasing from 10 to 75 emu g^–1 when increasing length of the IONRs, 5 nm in diameter, from 25 to 50 nm. The magnetic resonance imaging (MRI) contrast-enhancing effect, as measured in terms of the transverse relaxivity, <i>r</i>₂, increased from 670.6 to 905.5 mM^–1 s^–1, when increasing the length from 25 to 50 nm. When applied to the immunomagnetic cell separation of the transferrin receptor (TfR)-overexpressed medulloblastoma cells using transferrin (Tf) as the targeting ligand, Tf-conjugated IONRs can capture 92 ± 3% of the targeted cells under a given condition (2.0 × 10⁴ cells/mL, 0.2 mg Fe/mL concentration of magnetic materials, and 2.5 min of incubation time) compared to only 37 ± 2% when using the spherical IONPs, and 14 ± 2% when using commercially available magnetic beads, significantly improving the efficiency of separating the targeted cells

Insertion of an Isolable Dialkylstannylene into C–Cl Bonds of Acyl Chlorides Giving Acyl(chloro)stannanes

The reactions of isolable dialkylstannylene <b>1</b> with 1-adamantanoyl, 2,2-dimethylpropanoyl, benzoyl, and substituted benzoyl chlorides afford the corresponding acyl­(chloro)­stannanes in good yields. Similar reactions with more reactive acetyl and propanoyl chlorides do not give the corresponding insertion products but the corresponding dichlorostannane by the overreaction. The benzoyl­(chloro)­stannane reacts with acetyl chloride to afford the corresponding 1,2-dione and the dichlorostannane quantitatively. Acyl­(chloro)­stannanes obtained were fully characterized by multinuclear NMR spectroscopy, high-resolution mass spectrometry, and by single-crystal X-ray diffraction studies

Short-Term Reproducibility of Twenty-Four-Hour Intraocular Pressure Curves in Untreated Patients with Primary Open-Angle Glaucoma and Ocular Hypertension

<div><p>Purpose</p><p>To assess the short-term day-to-day reproducibility of 24-hour intraocular pressure (IOP) curves in various respects in untreated primary open-angle glaucoma (POAG) and ocular hypertension (OHT) patients.</p><p>Methods</p><p>47 subjects with POAG and 34 subjects with OHT underwent IOP measurements every 2 hours in both eyes for consecutive 48 hours by a non-contact tonometer (NCT). IOP values at each time point were recorded. Mean IOP, peak IOP, time difference of peak IOP between two days and IOP fluctuation were also calculated. Intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to evaluate reproducibility.</p><p>Results</p><p>ICCs of the entire IOP values for a complete 24-hour curve were 0.577 and 0.561 in POAG and OHT patients, respectively. ICCs of IOP values at different time points ranged from 0.384 (10am) to 0.686 (4am) in POAG patients and from 0.347 (6am) to 0.760 (4am) in OHT patients. ICCs of mean IOP, peak IOP and IOP fluctuation were respectively 0.832, 0.704, 0.367 in POAG patients and 0.867, 0.816 0.633 in OHT patients. Only 37.23% and 35.29% of the peak IOP time points appeared within the time difference of 2 hours in POAG and OHT patients, respectively, while 53.19% and 48.53% appeared within 4 hours in POAG and OHT patients, respectively.</p><p>Conclusion</p><p>A 24-hour IOP curve in a single day is not highly reproducible in short-term and has limited use for evaluating individual IOP condition. Mean IOP and peak IOP for a 24-hour IOP curve are useful parameters in clinical follow-up, while IOP value at a certain time point, IOP fluctuation and peak IOP time point should be interpreted with caution.</p></div

Twenty-Four-Hour IOP Curves in Two Days Described by Mean IOP Values at Different Time Points (Mean ± SD).

<p>Twenty-Four-Hour IOP Curves in Two Days Described by Mean IOP Values at Different Time Points (Mean ± SD).</p

The Eye Frequency of the Time Difference of Peak IOP Time Points Between Two Days.

<p>The Eye Frequency of the Time Difference of Peak IOP Time Points Between Two Days.</p

Mean IOP Values and ICCs at Each Time Point in/Between Two Days.

<p>^a Data are expressed as mean ± SD;</p><p>^b P<0.05;</p><p>^c P<0.01.</p><p>Mean IOP Values and ICCs at Each Time Point in/Between Two Days.</p

Reactions of an Isolable Dialkylstannylene with Carbon Disulfide and Related Heterocumulenes

The reaction of isolable dialkylstannylene <b>1</b> with an excess amount of CS₂ produces an isomeric mixture of 3,3′-distanna-2,2′,4,4′-tetra­thia­bicyclo­butylidene <b>8</b> and 3,7-distanna-2,4,6,8-tetra­thia­bicyclo­[3.3.0]­oct-1(5)-ene <b>9</b> with a ratio depending on the reaction conditions. Compounds <b>8</b> and <b>9</b> are separated by column chromatography and characterized by NMR spectroscopy and X-ray crystallography. Detailed investigation of the reaction has revealed that the initial product is <b>8</b>, which isomerizes to <b>9</b> irreversibly under the catalytic influence of <b>1</b> as a Lewis acid. The above view is supported by the theoretical DFT calculations. Treatment of <b>1</b> with ArNCO [Ar = 2,6-<i>i</i>Pr₂C₆H₃] affords the corresponding carbamoyl­(hydroxyl)­stannane <b>11</b> via the hydrolysis of the corresponding sila­aziridinone formed by the [1 + 2] cycloaddition reaction of <b>1</b> with the NC double bond of the isocyanate. Stannylene <b>1</b> reacts with ArNCS, giving a mixture of complex products, while <b>1</b> does not react with CO₂

Flow Chart of the Selection Process.

<p>Flow Chart of the Selection Process.</p

Demographic Data of the Subjects.

<p>^a Data are expressed as mean ± standard deviation (SD).</p><p>Demographic Data of the Subjects.</p

The Bland-Altman Plots for Different Parameters in POAG Group.

<p>The Bland-Altman Plots for Different Parameters in POAG Group.</p