A sample may be prepared and then analyzed using a liquid chromatography with tandem mass spectrometry system to determine presence and concentration of herbicide(s) present in the sample. In some examples, the method involves providing a sample containing one or more herbicides and adding a base to the sample. The base may increase the pH of the sample to ≥12, thereby hydrolyzing esters of the one or more herbicides. The method may further involve, subsequent to hydrolyzing the esters of the one or more herbicides, adding an acid to the sample so as to lower the pH of the sample to ≤3. Once prepared, the sample can be injected into a liquid chromatography instrument to separate the herbicide molecules from other molecules present in the sample before being ionized and characterized by mass-to-charge ratio and relative abundance using one or more mass spectrometers.

The current invention is based, at least in part, on the finding that the transverse nuclear magnetic spin relaxation time T2 and the transverse nuclear magnetic spin relaxation rate R2, respectively, of protons of water molecules in an aqueous solution comprising viral particles depends on the loading status (full vs. empty) of the viral particle. Thus, one aspect of the current invention is a method for determining the ratio of loaded viral particles to empty viral particles in a sample, comprising the steps of determining a nuclear magnetic resonance (NMR) parameter related to the protons of the water molecules present in an aqueous solution comprising a mixture of loaded and empty viral particles by applying an NMR measurement to the solution, and determining the ratio of loaded viral particles to empty viral particles with the NMR parameter determined in the previous step based on a calibration function.

A nucleophilic substitution reaction to crosslink cyclodextrin (CD) polymer with rigid aromatic groups, providing a high surface area, mesoporous CD-containing polymers (P-CDPs). The P-CDPs can be used for removing organic contaminants from water. By encapsulating pollutants to form well-defined host-guest complexes with complementary selectivities to activated carbon (AC) sorbents. The P-CDPs can rapidly sequester pharmaceuticals, pesticides, and other organic micropollutants, achieving equilibrium binding capacity in seconds with adsorption rate constants 15-200 times greater than ACs and nonporous CD sorbents. The CD polymer can be regenerated several times, through a room temperature washing procedure, with no loss in performance.

A nucleophilic substitution reaction to crosslink cyclodextrin (CD) polymer with rigid aromatic groups, providing a high surface area, mesoporous CD-containing polymers (P-CDPs). The P-CDPs can be used for removing organic contaminants from water. By encapsulating pollutants to form well-defined host-guest complexes with complementary selectivities to activated carbon (AC) sorbents. The P-CDPs can rapidly sequester pharmaceuticals, pesticides, and other organic micropollutants, achieving equilibrium binding capacity in seconds with adsorption rate constants 15-200 times greater than ACs and nonporous CD sorbents. The CD polymer can be regenerated several times, through a room temperature washing procedure, with no loss in performance.

A flow cell, for detecting a fluidic sample separated by a sample separation apparatus, includes a cuvette, a flow channel formed at least partially in the cuvette and configured to enable a flow of the separated fluidic sample through the flow channel, an electromagnetic radiation inlet at which an excitation electromagnetic radiation beam is couplable into the cuvette, and an electromagnetic radiation outlet at which an emission electromagnetic radiation beam, generated by an interaction between the excitation electromagnetic radiation beam and the separated fluidic sample, is couplable out of the cuvette. A geometry of the cuvette is configured so that at least one point at the excitation backside surface of the cuvette is outside of a direct field of view of the electromagnetic radiation outlet.

A flow cell, for detecting a fluidic sample separated by a sample separation apparatus, includes a cuvette, a flow channel formed at least partially in the cuvette and configured to enable a flow of the separated fluidic sample through the flow channel, an electromagnetic radiation inlet at which an excitation electromagnetic radiation beam is couplable into the cuvette, and an electromagnetic radiation outlet at which an emission electromagnetic radiation beam, generated by an interaction between the excitation electromagnetic radiation beam and the separated fluidic sample, is couplable out of the cuvette. A geometry of the cuvette is configured so that at least one point at the excitation backside surface of the cuvette is outside of a direct field of view of the electromagnetic radiation outlet.

Provided herein are in vitro methods of assaying an in vivo level of high molecular weight (HMW) species of a therapeutic protein. In exemplary embodiments, the method comprises (a) incubating a mixture comprising (i) a sample comprising the therapeutic protein and (ii) serum, or a depleted fraction thereof; and (b) assaying the level of HMW species of the therapeutic protein present in the mixture at one or more time points after step (a). Also methods of determining the in vivo reversibility of HMW species of a therapeutic protein are provided herein. In exemplary instances, the method comprises (A) assaying the in vivo level of high molecular weight (HMW) species of a therapeutic protein according to a presently disclosed in vitro method, and (B) comparing the level(s) of HMW species present in the mixture to the level of HMW species present in the sample prior to the incubating step.

Provided herein are in vitro methods of assaying an in vivo level of high molecular weight (HMW) species of a therapeutic protein. In exemplary embodiments, the method comprises (a) incubating a mixture comprising (i) a sample comprising the therapeutic protein and (ii) serum, or a depleted fraction thereof; and (b) assaying the level of HMW species of the therapeutic protein present in the mixture at one or more time points after step (a). Also methods of determining the in vivo reversibility of HMW species of a therapeutic protein are provided herein. In exemplary instances, the method comprises (A) assaying the in vivo level of high molecular weight (HMW) species of a therapeutic protein according to a presently disclosed in vitro method, and (B) comparing the level(s) of HMW species present in the mixture to the level of HMW species present in the sample prior to the incubating step.

The present invention considers bringing a mobile unit closer to the site of interest and conduct the quantification of the tracers by performing the detection methods in situ and in real time at the wellhead, and that can be moved to the site on numerous occasions for the preparation of results during the test where the quantification of tracers is necessary, helping to speed up and reduce times that, until now, have not been achieved with stationary laboratories and that depending on the laboratory can last up to three months providing results.

The present invention considers bringing a mobile unit closer to the site of interest and conduct the quantification of the tracers by performing the detection methods in situ and in real time at the wellhead, and that can be moved to the site on numerous occasions for the preparation of results during the test where the quantification of tracers is necessary, helping to speed up and reduce times that, until now, have not been achieved with stationary laboratories and that depending on the laboratory can last up to three months providing results.