Phosphate-buffered saline , preparation

FIGURE 9.9 Small dumbbell-shaped sample of recombinant resilin prepared with embedded fine stainless steel mesh tabs (left) and being tested in phosphate-buffered saline (PBS) (right). 

The specifications and standardization include raw materials, preparation method of the standard solution, concentration of proteins, and the main band on SDS-PAGE. The outline of the procedure for preparation of the calibrators is shovm in Eig. 4.2. Table 4.5 shows the raw materials and the preparation method of the initial extract. To prepare the calibrators, the raw materials are extracted by the standard solution containing SDS and mercaptoethanol. The initial extract is prepared by centrifugation and filtration of the extract. The diluted extract is then prepared by 10-fold dilution of the initial extract with phosphate-buffered saline (PBS pH 7.4). The protein concentration of the diluted extract is assayed using the 2-D Quant kit (Amersham Bio Sciences). The standard solution is then... 

Preparations of PEG-modified proteins. A. SC-PEG (1 g, 0.2 mmol) was added to a stirred solution of Bovine Serum Albumin (BSA) (100 mg, 1.5 x 10 6 mol) in 0.1 M sodium phosphate, pH 7.8 (60 mL). Sodium hydroxide (0.5 N) was used to maintain pH 7.8 for 30 min. The excess of free PEG was removed by diafiltration using 50 mM phosphate buffered saline. Approximately 30 amino groups of the native protein were modified as determined by trinitrobenzenesulfonate (TNBS) assay (28). The same degree of modification was obtained when the experiment was repeated under identical conditions using SS-PEG instead of SC-PEG. 

Concentration and MWD of F-PHEA After Absorption. F-PHEA was determined in perfusate samples by quantitative GPC relative to a freshly prepared F-PHEA standard run on the same day. Either a mixed-bed column (12 x 300 mm Sephacryl S-200 Sephadex G-25 SF 3 1, Pharmacia LKB) or a Separon HEMA-Bio 40 column (8 x 250 mm 10 pm particle size, Tessek A/S, Aarhus, Denmark) was used with a 20 pL injection volume. A mobile phase of pH 7.4 phosphate buffered saline (0.05 M phosphate, 0.15 M NaCl) was supplied (Model LC-7A Bio Liquid Chromatograph, Shimadzu Corporation, Kyoto, Japan) at 0.5 or 1 mL/min. Fluorescent detection was employed (Model RF-535 Fluorescence HPLC Monitor,... 

Kreuter and Speiser [77] developed a dispersion polymerization producing adjuvant nanospheres of polymethylmethacrylate) (PMMA). The monomer is dissolved in phosphate buffered saline and initiated by gamma radiation in the presence and absence of influenza virions. These systems showed enhanced adjuvant effect over aluminum hydroxide and prolonged antibody response. PMMA particles could be distinguished by TEM studies and the particle size was reported elsewhere to be 130 nm by photon correlation spectroscopy [75], The particle size could be reduced, producing monodisperse particles by inclusion of protective colloids, such as proteins or casein [40], Poly(methylmethacrylate) nanoparticles are also prepared... 

A confluent monolayer of Madin-Darby canine kidney (MDCK) cells was grown in 96-well plates. Serial tenfold dilutions in minimal essential medium were prepared from the aliquots of allantoic fluid taken from the irradiated specimen. These dilutions were applied to MDCK cells and incubated for 48 h at 36 °C in 5% C02. The cells were then washed two times for 5 min with phosphate buffered saline (PBS) and incubated for 1 h with 100 pi of 0.5 mg/ml solution of 3-(4,5-dimethyl-thiazolyl-2) 2,5-diphenyltetrazolium bromide (MTT, ICN Biochemicals Inc., Aurora, Ohio). After lh, the colored deposit was dissolved in 100 pi DMSO, and optical density in the wells was measured on plate reader Victor 1420 (Perkin Elmer, Finland). Based on the data obtained, the infectious titer of the vims was determined as a decimal logarithm of reciprocal to the dilution of the specimen causing destruction of 50% of cells. The inhibiting action of irradiation was evaluated by decreasing the vims titer. 

A Working Solution of the stain should be prepared just before use, by combining 10 ml of 0.1% Triton X-100 in phosphate-buffered saline, 2 mg RNase (DNase-free, Sigma), and 200 pi PI solution (Sigma, 1 mg/ml in distilled water). Stock solutions of Triton X-100 and PI should be stored at 4°C. Centrifuge the ethanol-fixed cells (200 x g for 5 min) and discard the supernatant, removing it completely. 

Prepare competitor protein buffer detergent solution 4 mg/mL normal goat globulin or other competitor protein, (such as fetal calf serum, bovine serum albumin, bovine plasma, and so forth), and 0.1% saponin (Sigma, St. Louis, MO) in phosphate-buffered saline (NGG-sap-PBS). 

Water extract of W. sativa was prepared, dried and powdered. Powder was dissolved in phosphate buffer saline (pH 6.4) and centrifuged at 10.000 rpm for 30 min at 4 °C. The supernatant was collected as the soluble extract by removing the oily layer and unsoluble pellet. Protein concentration of the soluble extract was determined with Bradford method. Then proteins dialyzed against 0.05 M phosphate buffer (pH 6.4) using 3500 MW cut off dialyzing bags and centrifuged. 

When liquid samples such as serum, plasma, milk, or honey are not to be extracted using direct liquid-liquid partitions with organic solvents but through use of solid-phase extraction or matrix solid-phase dispersion techniques, dilution with water (323, 324), phosphate buffer saline (325), or phosphoric acid (326, 327) is often the only sample preparation procedure applied. Milk analysis sometimes requires further pretreatment for fat removal (328). Centrifugation at about 7000g at 4-10 C for 20 min is the usually applied procedure for making the fat floating on top of milk readily eliminated. 

Monoclonal antibodies against STR were used for the preparation of an immunoaffinity chromatography column. Milk samples were defatted by centrifugation and diluted with phosphate-buffered saline. After loading onto the column, this was washed with saline, and STR and DIHS were eluted with the glycine-HCl buffer. The column bounded 80.4% and 88.7% of milk samples containing 100 ppb STR and DIHS, respectively (117). 

Measurement. The measurement apparatus for the in vitro test of this sensor is shown in Figure 4. The sensor was dipped into the flask containing 100 ml of phosphate buffered saline solution, pH 7.4, and the output was measured with respect to stepwise changed glucose concentrations of 0 to 2000 mg/dl under the oxygen tensions of 5 to 21%, which prepared by mixing air and N2 gas. 

Prepare the antibody for reduction. For labeling IgG antibodies with thiol-reactive reagents, the antibody should be at 5-10 mg of pro-tein/mL in 20 mM sodium or potassium phosphate buffer, pH 7.5-8.0 containing 150 mill NaCl or 10 mM phosphate-buffered saline ethylene diamine tetraacetic acid (PBS-EDTA). When biotin maleimide or biocytin maleimide derivatives are used, the buffer used for the reduction and subsequent steps should be at pH 6.5-7.2. 

In contrast to tissues, tissue culture cells are readily lysed with detergent [11]. Adherent cells from a culture plate are first scraped using a rubber policeman into a small volume of phosphate-buffered saline (137 mMNaCl, 2.7 mM KC1, 4.3 mM Na2HP04, 1.4 mM KH2P04, pH 7.3) and harvested by centrifugation at 1500 x g for 10 minutes at 4°C. The cellular pellet is resuspended in ice-cold TE so that 1 mL contains 100 million cells. After the addition of 10 volumes of freshly prepared digestion buffer (10 mM Tris-Cl, pH 8, 0.05 EDTA, pH 8, 0.5% Sarcosyl, and 100 pg/mL proteinase K), the sample is incubated at 50°C for 3 hours. DNA is recovered by ethanol precipitation after extraction with phenol, phenol-chloroform, and chloroform as described earlier. 

The technique reported, for pre-embedding scarce biological specimens in BSA and BA, applies to tissues or cells, prepared as pellet or suspension. Prior to pre-embedding, the biological specimens are fixed in 4% PF for 10 min for processing for LM, or 2.5% GA for 10 min for processing for EM. The biological specimens are prepared in 23.1 pi of phosphate buffer saline (PBS), by immersion for tissues or cell pellets, or resuspension for cell... 

The most thorough investigation in this area was that of Harrison and Royle43 on astatination of rabbit immunoglobulin (IgG) which could be used in animal experiments. PAtBA was produced with > 90% radiochemical yield, and a reproducible overall yield of > 30% for labelled protein was obtained with negligible deastatination of the latter in vivo. These favourable results could be achieved most probably due to the fact that the PAtBA was prepared without an iodine carrier and that the micro amounts of the product were purified from the macro amounts of contaminates by HPLC. To bind PAtBA to the protein, acylation with mixed anhydride was used. Preparation of the mixed anhydride 7 (equation 5) could be carried out in about 20 minutes at ca 0 °C. For astatination rabbit IgG protein is dissolved in borate buffer (pH = 9.3) and then added to 7 (see equation 6) the procedure takes about 1 hour at ca 15 °C. The astatinated protein is separated from non-conjugated materials by gel filtration and eluted from the column by phosphate-buffered saline. 

The effects of conditioning layers of two important blood serum proteins, albumin and fibrinogen were investigated. Protein adsorption was studied using bovine serum albumin (BSA) and fibrinogen (F) from Sigma. The samples were incubated for 3 h at 37°C in solutions of albumin (1 mg/mL) and fibrinogen (0.2 mg/mL) prepared in phosphate buffered saline (PBS, 0.01 M phosphate buffer, 0.0027 M KC1, 0.137 MNaCl, pH 7.4). After the incubation period, the samples were rinsed 3 times with PBS and analyzed by the various surface characterization techniques. 

Biological autofluorescence in mammalian cells due to flavin coenzymes (FAD and FMN absorption, 450 nm emission, 515 nm) and reduced pyridine nucleotides (NADH absorption, 340 nm emission, 460 nm) can be problematic in the detection of fluorescence probes in tissues and cells. Fixation with aldehydes, particularly glutaraldehyde, can result in high levels of autofluorescence. This can be minimized in fixed cells by washing with 0.1% sodium borohydride in phosphate-buffered saline (5) prior to antibody incubation. Problems due to autofluorescence can be minimized by selecting probes and optical filters that maximize the fluorescence signal relative to the autofluorescence. Other factors that limit IF include the performance of the detection instrument (i.e. how well the microscope has been calibrated and set), the specificity of the antibodies, and the specimen preparation. 

If nasal inoculation is to be performed then the animals must first be anaesthetized by intraperitoneal injection of chloral hydrate. For this, a 5.7% (w/v) solution is prepared in phosphate-buffered saline (PBS) pH 7.4, and 250 pL injected per 50 g of body weight. 

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