Abstract: A method of characterizing an oil sample includes: flowing a first sample containing an oil through a microfluidic device that has a microfluidic filter while controlling the temperature of the first sample such that it is above wax appearance temperature for the oil and measuring and analyzing pressure difference across the filter over time to detect the presence of fines in the oil. The method further includes: flowing a second sample containing the oil through the microfluidic device while controlling the temperature of the second sample such that the temperature of the second sample is lower than wax appearance temperature for the oil and measuring and analyzing pressure difference across the filter over time as the second sample is filtered to detect the presence of wax in the oil.

Abstract: A method and system for detecting mercury in a hydrocarbon-containing fluid stores a sample of the hydrocarbon-containing fluid in a first reservoir. A liquid phase reagent solution is stored in a second reservoir. The liquid phase reagent solution includes nanoparticles with an affinity to mercury, wherein the nanoparticles are suspended as a colloid in the liquid phase reagent solution. The sample of the hydrocarbon-containing fluid is delivered from the first reservoir into a first port of a fluidic device while the liquid phase reagent solution is delivered from the second reservoir into a second port of the fluidic device such that the fluidic device produces slug flow. The slug flow is subject to optical analysis that determines concentration of mercury in the sample of the hydrocarbon-containing fluid.

Abstract: A method of characterizing an oil sample includes: i) flowing a first sample containing an oil through a microfluidic device that has a microfluidic filter while controlling the temperature of the first sample such that it is above wax appearance temperature for the oil; ii) in conjunction with i), using the microfluidic filter to perform filtering operations that selectively block fines contained in the oil from passing through the filter; iii) in conjunction with i) and ii), measuring and analyzing pressure difference across the filter over time to detect the presence of fines in the oil; iv) flowing a second sample containing the oil through the microfluidic device while controlling the temperature of the second sample such that the temperature of the second sample is lower than wax appearance temperature for the oil; v) in conjunction with iv), using the filter to perform microfluidic filtering operations that selectively block at least one of wax that crystallizes from the oil and fines contained in the

Abstract: A method and system for detecting mercury in a hydrocarbon-containing fluid stores a sample of the hydrocarbon-containing fluid in a first reservoir. A liquid phase reagent solution is stored in a second reservoir. The liquid phase reagent solution includes nanoparticles with an affinity to mercury, wherein the nanoparticles are suspended as a colloid in the liquid phase reagent solution. The sample of the hydrocarbon-containing fluid is delivered from the first reservoir into a first port of a fluidic device while the liquid phase reagent solution is delivered from the second reservoir into a second port of the fluidic device such that the fluidic device produces slug flow. The slug flow is subject to optical analysis that determines concentration of mercury in the sample of the hydrocarbon-containing fluid.

Abstract: A method for determining an asphaltene onset condition of a crude oil is provided. The method includes receiving a crude oil within a downhole tool inside a well and taking a first measurement of an optical property of the received crude oil. The method also includes lowering the pressure or temperature of the crude oil after taking the first measurement of the optical property to cause aggregation of asphaltenes in the crude oil, and then separating aggregated asphaltenes from the crude oil. Further, the method includes taking a second measurement of the optical property of the crude oil within the downhole tool after separating aggregated asphaltenes from the crude oil and determining an asphaltene onset condition of the crude oil through comparison of the first and second measurements of the optical property. Additional methods, systems, and devices are also disclosed.

Abstract: A method for determining an asphaltene onset condition of a crude oil is provided. The method includes receiving a crude oil within a downhole tool inside a well and taking a first measurement of an optical property of the received crude oil. The method also includes lowering the pressure or temperature of the crude oil after taking the first measurement of the optical property to cause aggregation of asphaltenes in the crude oil, and then separating aggregated asphaltenes from the crude oil. Further, the method includes taking a second measurement of the optical property of the crude oil within the downhole tool after separating aggregated asphaltenes from the crude oil and determining an asphaltene onset condition of the crude oil through comparison of the first and second measurements of the optical property. Additional methods, systems, and devices are also disclosed.

Abstract: A method includes providing a water sample for analysis at a well site, or at a location proximate the well site, where the water sample is collected from at least one water source and the water sample comprises at least one analyte. The water sample and a reagent are introduced into a microfluidic mixing cell to produce a mixture of the reagent and water sample, and the mixture has a detectable characteristic indicative of concentration of the at least one analyate in the water sample. The detectable characteristic is measured by spectrophotometry to determine concentration of the at least one analyte. Then a subterranean formation treatment fluid is prepared using water from the at least one water source based on the concentration of the at least one analyte. The introducing into the microfluidic mixing cell and the measuring by spectrophotometry are conducted over an elapsed time period of about 5 minutes or less.

Abstract: A method for determining an asphaltene yield curve and an asphaltene flocculation point includes obtaining a crude oil sample and measuring an optical spectrum of the crude oil sample. A titrant is then mixed with the crude oil sample at different concentrations. At each concentration, precipitated asphaltenes are filtered from the mixture and the optical spectrum of the filtrate is measured. The optical spectrum of the filtrate is then subtracted from the optical spectrum of the crude oil sample. A fractional asphaltene precipitation is determined for each concentration of titrant. A flocculation point is determined corresponding to an inflection point in the fractional asphaltene precipitation for each concentration of titrant.

Abstract: A method for determining an asphaltene yield curve and an asphaltene flocculation point includes obtaining a crude oil sample and measuring an optical spectrum of the crude oil sample. A titrant is then mixed with the crude oil sample at different concentrations. At each concentration, precipitated asphaltenes are filtered from the mixture and the optical spectrum of the filtrate is measured. The optical spectrum of the filtrate is then subtracted from the optical spectrum of the crude oil sample. A fractional asphaltene precipitation is determined for each concentration of titrant. A flocculation point is determined corresponding to an inflection point in the fractional asphaltene precipitation for each concentration of titrant.

Abstract: The present invention provides for a method of implementing fluorescent in situ hybridization (FISH) or other cellular analysis processes using intact cells within a microfluidic, chip-based, apparatus. The invention further provides for a method of cellular immobilization within a microfluidic device. Also provided is a method for automated analysis of FISH or other cellular analysis using discrete colormetric probes.