A thin-layer chromatography device can be used to determine or select a surfactant solution for use during hydrocarbon-fluid production operations. The thin-layer chromatography device can include a chamber that can receive a surfactant solution that includes a surfactant and a fluid. The thin-layer chromatography device can also include a substrate that can be coated with a layer of adsorbent material to form a thin-layer substrate and a hydrocarbon fluid can be disposed on the thin-layer substrate. The thin-layer substrate, along with the hydrocarbon fluid, can be positioned within the chamber to determine a mobility index of the hydrocarbon fluid when the hydrocarbon fluid contacts the surfactant solution. The mobility index can indicate an eluting capability of the surfactant solution with respect to the hydrocarbon fluid and can be used to select the surfactant solution to be injected into a wellbore that includes the hydrocarbon fluid to enhance hydrocarbon-fluid production operations.

Methods, kits, and systems are provided for separating, immobilizing, and/or detecting analytes of one or more samples using dipsticks. A dipstick is an object that can be embedded and subsequently removed from a separation medium, and to which analytes can be immobilized while the object is embedded in the separation medium. Examples of separation media include an electrophoresis gel of any format and a stationary phase for column chromatography. Embodiments of the present methods include applying a sample to a separation medium; separating analytes of the sample in the separation medium along a separation axis; immobilizing the analytes on a dipstick embedded in the separation medium; removing the dipstick from the separation medium; and detecting the analytes immobilized on the removed dipstick.

The present invention provides novel chromatographic materials, e.g., for chromatographic separations, processes for its preparation and separations devices containing the chromatographic material; separations devices, chromatographic columns and kits comprising the same; and methods for the preparation thereof. The chromatographic materials of the invention are high purity chromatographic materials comprising a chromatographic surface wherein the chromatographic surface comprises a hydrophobic surface group and one or more ionizable modifier.

The present invention provides novel chromatographic materials, e.g., for chromatographic separations, processes for its preparation and separations devices containing the chromatographic material; separations devices, chromatographic columns and kits comprising the same; and methods for the preparation thereof. The chromatographic materials of the invention are high purity chromatographic materials comprising a chromatographic surface wherein the chromatographic surface comprises a hydrophobic surface group and one or more ionizable modifier.

Provided is a separation chromatography supporting device capable of predicting, using a result of thin-layer chromatography or column chromatography, a result of liquid chromatography for a wide range of compounds with high accuracy and setting an optimum separation condition. The separation chromatography supporting device includes a calculation formula acquisition unit, and provides information related to separation in column chromatography based on an actually measured value of an Rf value when a mixed solvent having a mixing ratio B of two specific types of solvents measured by thin-layer chromatography or liquid chromatography is used. The calculation formula acquisition unit acquires a.sub.1 in a relational formula of

[00001]$\begin{array}{cc}\mathrm{Rf}=a_{1}B+b_1& \left(1\right)\end{array}$ or a.sub.2 in a relational formula of

[00002]$\begin{array}{cc}\log k^{}=a_2\log B+b_2& \left(2\right)\end{array}$$\begin{array}{cc}(\mathrm{where}\mathrm{retention}\mathrm{ratio}:k^{}=\left(t_R-t_0\right)/t_0& \left(3\right)\end{array}$ solvent ratio: B) based on B and Rf that are actually measured values as one measurement result by TLC.

Provided is a separation chromatography supporting device capable of predicting, using a result of thin-layer chromatography or column chromatography, a result of liquid chromatography for a wide range of compounds with high accuracy and setting an optimum separation condition. The separation chromatography supporting device includes a calculation formula acquisition unit, and provides information related to separation in column chromatography based on an actually measured value of an Rf value when a mixed solvent having a mixing ratio B of two specific types of solvents measured by thin-layer chromatography or liquid chromatography is used. The calculation formula acquisition unit acquires a.sub.1 in a relational formula of

[00001]$\begin{array}{cc}\mathrm{Rf}=a_{1}B+b_1& \left(1\right)\end{array}$ or a.sub.2 in a relational formula of

[00002]$\begin{array}{cc}\log k^{}=a_2\log B+b_2& \left(2\right)\end{array}$$\begin{array}{cc}(\mathrm{where}\mathrm{retention}\mathrm{ratio}:k^{}=\left(t_R-t_0\right)/t_0& \left(3\right)\end{array}$ solvent ratio: B) based on B and Rf that are actually measured values as one measurement result by TLC.

This invention discloses a new class of pH indicators suitable for use in agricultural compounds. The class comprises naturally occurring substances which are extracts from grape skins, cabbage and lecithin. Safety concerns are now causing regulatory bodies to prohibit use of chemical pH indicators in compounds which are used for crops and animals. The naturally occurring compounds of this invention satisfy these concerns of the regulators and function as well as chemical indicators of the prior art.

An apparatus for heating a GC column is described. The apparatus includes first and second temperature sensors. Temperature data are used to set power provided to a heating element of the apparatus.

In one aspect, the inventive concepts disclosed herein are directed to a lateral flow assay comprising: one or more chromatographic substrates, a sample application site, a first capture site, and a second capture site. The first capture site comprising an anti-hCG capture antibody with broad affinity for a group of multiple hCG variants and the second capture site comprising an anti-hCG capture antibody that is specific to a first variant of hCG. Additional aspects of the invention disclose using the later flow assay to determine a ratio of the first variant of hCG to the group of multiple hCG variants.

Methods, kits, and systems are provided for separating, immobilizing, and/or detecting analytes of one or more samples using dipsticks. A dipstick is an object that can be embedded and subsequently removed from a separation medium, and to which analytes can be immobilized while the object is embedded in the separation medium. Examples of separation media include an electrophoresis gel of any format and a stationary phase for column chromatography. Embodiments of the present methods include applying a sample to a separation medium; separating analytes of the sample in the separation medium along a separation axis; immobilizing the analytes on a dipstick embedded in the separation medium; removing the dipstick from the separation medium; and detecting the analytes immobilized on the removed dipstick.