Dilutions series

Data Analysis The results were plotted at first glance a linear regression of absorbance versus concentration appeared appropriate. The two dilution series individually yielded the figures of merit given in Table 4.17, bottom. The two regression lines are indistinguishable, have tightly defined slopes. 

Under the aforementioned circumstances, the two-step reaction 4.53 and the associated eqns. 4.54-4.62 are equally valid on the understanding that HS represents Hcres, etc. further, it must be realized that during titration various amounts of HX and B are simultaneously present. Therefore, from previous measurement of the conductivities (k) of dilution series of the separate acids, bases and salts in m-cresol, the overall constants KHX, KB and KBH+X were calculated by the Fuoss and Kraus method66,67 (with the use of e = 12.5 and viscosity = 0.208 P for m-cresol). For C6H6S03H and HC1 it was necessary to calculate the equivalent conductivity at zero concentration from the equation... 

The next question to be addressed is what the maximum concentration of inhibitor should be at the start of the 1.5-fold dilution series. Murphy suggests starting the dilution series at a concentration of inhibitor equal to 30[ ]T (or more correctly 30 times ones best estimate of total enzyme concentration). Simulations suggest that this dilution scheme will provide adequate data points within region B for inhibitors with potencies ranging from A fpp/[ ]T = 0.01 to 10. 

Toxicity analyses were performed by the individual exposure of zebrafish embryos to the different PBDEs commercial mixtures degradation samples from 4 to 48 hours post-fertilization (hpf), including negative controls and controls of solvent in the test. Additionally, two independent experiments were performed on undiluted samples and a last experiment was performed on a dilution series of 50%, 5% and 0.5% of the original samples. The embryos were observed after 24 and 48 hpf, and categorized as dead or alive. 

A process control is just that, a control for the stain process. While the concept can be extended to the primary epitope also, this may not be practical in all cases. Purified protein epitopes are very expensive, and adding a dilution series of primary epitope to a control slide would create a unique and possibly... 

Factor of dilution series 3 instead of 1.8 (1.8 being the lowest flow of the odorous and inodorous gases, in m3/h, at the outlet of the olfactometer, at the time of sniffing , cf. french standard, para. 4.1). 

EROD activity is measured in the H411E cells as follows. The cells are seeded at 7,000 cells per well in 250 xL of Dulbecco s modified Eagles culture media (Tillitt et al., 1991). After an initial incubation period of 24 hours, the cells are dosed with 5 xL volumes of eiuiched SPMD extracts (cleanup of extracts generally includes dialysis and size exclusion chromatography [SEC]) and incubated for an additional 72 hours. Sample dose is typically expressed as g-equivalents triolein or whole SPMD per mg cellular protein. Multiple exposures are performed at each of six (typically) sample concentrations, using a dilution series. Afterwards, the microtiter plates are washed three times with distilled water to lyse the cells. EROD activity (pmol mg cellular protein per min) in each sample is measured... 

Antigen arrays, also described as reverse-phase protein arrays (Paweletz et al., 2001), involve the immobilization of proteins to serve as bait for various protein-protein interactions (Sreekumar and Chinnaiyan, 2002). For example, Joos et al. (2000) printed down various autoantigens present in sera with known associations with various autoimmune diseases such as Graves disease lupus connective tissue disease, and others. The group then screened various sera for the presence of autoantibodies. By immobilizing on the array a serial dilution series for each antigen, the titers for these antibodies could be determined. 

Indicate the concentrations or dilutions used in the dilution series on the Y-axis. 

Robotic printing lysates in replicate or dilution series on multiple parallel arrays... 

To prevent systematic mistakes in the dilution series of the ligand standard solutions, leading to relative shifts in the [L]-control maps, we carried out independent control catalyses on the 250-ml scale. For the ([L]o/[Ni]o) ratio we selected inflection points in the varying product distribution of the [L]-control maps. In Fig. 3.2-2 is exemplified the [L]-control map of the catalytic system nickel/phenyl-diphenoxi-phos-phine/butadiene. ... 

Determine the amount of protein necessary for saturation of the gold sol Pipet 0.5 ml of the dialyzed colloidal gold into Eppendorf tubes and add 0.1 ml of a dilution series of the dialyzed protein to... 

RT for 30 min. Remove blocking solution, rinse once with Soln. B and add 100 pl/well of a dilution series (e.g., 1 500,1 1500,1 4500, 1 13 500,1 40 500,1 121 500,1 364 500 in TBS) of antibody-enzyme conjugate to the wells. Shake at RT for 30 min, remove conjugate solution, knock out the plate on paper tissue, and rinse three times with Soln. B. 

Dilute a membrane preparation to about 0.4 mg protein per milliter or cell suspensions to about 10 cells/ml with Soln. A. Prepare four 1 3 dilution series of Soln. B using Soln. A as diluent (dilutions 0 to 4 ). Pipet 50 pi of dilutions 0 to 4 as duplicates into scintillation vials to define the total radioactivity values Totalo to Total4. ... 

Two independent replicate solutions of the preparation being examined at the dilution with which the test for interfering factors was completed. Use water BET to make two independent dilution series of four tubes containing the preparation being examined at concentrations of 1, 1/2, 1/4, and 1/8 relative to the dilution with which the test for interfering factors was completed. 

For semiquantitative gelation method, the geometric mean of the endotoxin concentration = antilog (Xe//), where Xe is the sum of the log endpoint concentrations of the dilution series used, and/ is the number of replicate test tubes. 

In early studies, the criterion for pheromonal activity was designated as the lowest concentration (ppm) of the candidate compound in a 10-fold dilution series that elicited a demonstrable response from test mites. Activity was expressed in terms of the dose of the test compound applied to the filter paper dispenser. More recently, more sophisticated bioassays using arenas have been developed, in which the movements of mites toward or away from test stimuli can be quantified (Nishimura et al., 2002). 

On the next day, monitor the titer of the selection by counting colonies on the plates from the dilution series. Add 1-2 mL 2X TY, containing 15% glycerol to the Bio-Assay dish, and loosen the bacteria with a glass spreader... 

Dispense 0 to 100 il standard protein to appropriately labeled tubes and bring the total volume to 100 pi with sample buffer or solvent to prepare a dilution series from 10 to 100 pg. 

Prepare a dilution series of 2 mg/ml BSA in sample buffer or diluent to cover a range from 125 to 2000 pg/ml. 

Prepare a dilution series of BSA standard in buffer to cover the range 125 to 2000... 

Select a protein to use as the standard (see Strategic Planning) and prepare a dilution series with buffer to cover the range 10 to 160 mg/ml. 

Prepare a dilution series from protein standard (e.g., 2 mg/ml BSA) and sample buffer to cover the range 100 to 1000 pg/ml. 

Table E3.3.1 Dilution Series for the D-Galacturonic Acid Standard... 

It may be necessary to prepare an alternative dilution series depending on the uronic acid content of your samples. 

Dilution analysis time depends on the number of dilutions to be conducted. A three-dilution series with duplication is composed of six SPME single samplings and GC/O runs. 

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