Fluorescence spectrophotometer, Perkin-Elmer

The HPLC was a Du Pont 8800 quaternary solvent system with a Hewlett-Packard (HP) 1040A photodiode array detector (5-8). Flexible disks were used for data storage, and postrun data evaluation was performed by the detector s computer (HP 85). Samples were injected with a loop injector 10 p,L was used for analytical scale, and 200 jlL was used for preparative scale. Spectra were run on a spectrophotometer (Perkin-Elmer Lambda 3) for static absorbance and on a spectrofluo-rometer (Perkin-Elmer MPF-66) for fluorescence. Field-ionization mass spectra were obtained at a resolution of 45,000 (corresponding to a 0.01-daltons error for a mass of 450). 

All samples were monitored using a Perkin-Elmer 650-10S Fluorescence Spectrophotometer. Fluorescence excitation and emission wavelengths for the PAHs in this study were obtained from Berlman (24). The resulting spectra were analyzed using an Apple 11+ computer by integrating peak areas to determine total changes in... 

Ultraviolet absorption spectra were obtained from a Cary 118C Spectrophotometer. Luminescence measurements were obtained from a Perkin-Elmer Model MPF-3 Fluorescence Spectrophotometer equipped with Corrected Spectra, Phosphorescence and Front Surface Accessories. A Tektronix Model 510N Storage Oscilloscope was used for luminescence lifetime measurements. Fiber irradiation photolyses were carried out in a Rayonet Type RS Model RPR-208 Preparative Photochemical Reactor equipped with a MGR-100 Merry-go-Round assembly. 

Analyses I.r. spectra were measured as smears on sodium chloride plates or as a solution in carbon tetrachloride using a Perkin-Elmer 567 grating spectrophotometer, while u.v. spectra were measured as a solution in hexane (spectroscopic grade) using a Unicam SP 1700 instrument. Fluorescence and phosphorescence spectra were recorded as described elsewhere (5, 6). 

Methods. Absorption spectra were recorded using an Hitachi model 150-20 spectrophotometer/data processor system. Uncorrected steady-state fluorescence emission spectra were recorded using a Perkin-Elmer MPF-44A spectrofluorimeter. These spectra were collected and stored using a dedicated microcomputer and then transferred to a VAX 11/780 computer for analysis. Fluorescence spectra were corrected subsequently for the response characteristics of the detector (21). Values of the fluorescence quantum yield, <) , were determined relative to either quinine bisulfate in IN H2S04 )>f =... 

Instrumentation. The steady-state fluorescence spectra were measured with Perkin-Elmer MPF-44B fluorescence spectrophotometer. The single-photon counting instrument for fluorescence lifetime measurements was assembled in-house from components obtained from EG G ORTEC. A PRA-510B light pulser filled with gas was used as the excitation source. Instrument response function was obtained with DuPont Ludox scatter solution at the excitation wavelength. 

Dry Oil Oxidation Fluorescence may be measured within or over an oil or within or over an emulsion of lipid in water providing the pH is below 5.5. When plate fluorescence is to be measured, solid sample fluorescence spectrophotometry is necessary (23). A Hitachi Solid Sample Holder Attachment for Model MPF-2A Hitachi-Perkin Elmer Fluorescence Spectrophotometer (Figure 4) was... 

A Perkin-Elmer MPF-2A Fluorescence Spectrophotometer was used to determine the excitation and emission wavelengths required for achieving maximum fluorescence intensity for the pesticides studied. The MPF-2A contained a 150 watt xenon arc and an excitation monochromator with a grating blazed at 300 nm as the excitation unit a Hamamatsu R 777 photomultiplier tube (sensitivity range 185 - 850 nm) and an emission monochromator grating blazed at 300 nm as the emission detection unit. A DuPont Model 848 Liquid Chromatograph was used for HPLC (Figure 2). The accessory injection device included a Rheodyne Model 70-10 six-port sample injection valve fitted with a 20 y liter sample loop. A Whatman HPLC column 4.6 mm x 25 cm that contained Partisil PXS 1025 PAC (a bonded cyano-amino polar phase unspecified by the manufacturer) was used with various mobile phases at ambient temperature and a flowrate of 1.25 ml/minute. 

Absorption spectra were recorded in a Perkin-Elmer spectrophotometer, and fluorescence spectra were recorded on a Perkin-Elmer Ul+B spectrofluorimeter. Flash photolysis studies were carried out using an excimer laser, X excitation = 3080A°, a ruby laser, X excitation = 3 71A°, or a nitrogen laser, X excitation = 3391A°. The system has been described previously. 

CFDA (Sigma) is used at 40 )Ug/ml final concentration in serum free medium, 0.1% BSA, pH 6.0, for 30 min at 37°C. At the end of the assay, adherent labeled tumor cells are placed in 0.2% SDS for 30 min at 37°C to release the fluorescent marker. Three volumes of calcium-magnesium-free-PBS are added, and the fluorescence of the cell lysate is measured with a Perkin-Elmer LS-5 luminescence spectrophotometer (excitation maximum 485 nm, emission maximum 538 nm) (Price et al., 1995). 

The 30-mm sediment slices of the segmented cylindrical cores obtained from box coring at the seven stations were dried, pulverized, and thoroughly mixed to yield a uniform sample for analysis. Sediment from each of these slices was analyzed by two independent methods. The first method used a Perkin-Elmer model 5000 atomic absorption spectrophotometer (AA) for the elements Fe, Mn, Ti, Pb, Zn, Cu, Cr, Ni, Co, Hg, and Cd (9). The second method utilized a Philips PW 1410 X-ray fluorescence spectrometer for the analysis of elements Fe, Mn, Ti, Ca, K, P, Si, Al, Mg, Na, Pb, Zn, Cu, Cr, V, and Ba (10). The AA analysis was chosen because of the known accuracy and sensitivity to a wide spectrum of elements. The XRF analysis was chosen for its accuracy and similar nondestructive mode of analysis equivalent to the shipboard XRF analysis. Good agreement between the AA and the XRF values was felt to be imperative because the Philips XRF equipment was to be used in the land-based multielement analysis of the CS -collected sediment samples. 

To determine the survivability for a TSP, samples were thermally cycled in a Thermoline 46200 high-temperature furnace. The furnace controls were set to raise the temperature to some predetermined value. The sample was then allowed to remain at this high temperature for 1 hr or more, followed by cooling to ambient room conditions. To quantify the fluorescence efficiency of phosphor suspended in the TSP, a Perkin Elmer LS-50B spectrophotometer was used to measure the emission spectrum of the sample after each thermal cycle. For each TSP mixture, two samples were made. The first sample was heated through the curing cycle and used as a control. The second was thermally cycled... 

A Perkin-Elmer LS5 fluorescence spectrophotometer was used for fluorescence intensity measurements. The excitation wavelength was set at 280 nm and the emission spectra were recorded between 310 and 480 nm. The protein concentration was 0.05 mg/ml in all experiments. The maximum difference in fluorescence intensity for the native and denatured enzyme was observed at 345 nm (Figure 2). Therefore, the... 

Instrumentation. Absorption spectra for the pyrenyl dye were obtained by using a Perkin-Elmer Lambda 2 UVA is/NIR spectrophotometer. The spectrophotometer is interface to a 286 computer to store spectra and control the instrument. Each spectrum was recorded using a PECSS program (Perkin-Elmer). Fluorescence spectra were recorded on an SLM 8000 spectrofluorometer interfaced to an IBM PS/2 computer. 

Emission spectra and absorption spectra were recorded on a Perkin-Elmer 650-iOS Fluorescence Spectrophotometer and a Perkin-Elmer 320 tn/ Spectrophotometer, respectively. Fluorescence decay data were obtained on a single-photon-counting apparatus from Photochemical Research Associates. The samples were bubbled witli nitrogen for the steady-state fluorescence spectra and the fluorescence decay measurements. In some cases, front face spectra were taken. The data were analyzed by a software package from PRA based on the iterative convolution method. NMR spectra were obtained on a JEOL FX90Q, and FTIR spectra were recorded on a Nicolet 5DX. The elemental analyses were conducted by M-H-W Laboratories of Phoenix, AZ. 

Steady state absorption spectra and emission spectra were recorded on a Perkin-Elmer 552 UV-Vis and MPF-44B fluorescence spectrophotometer respectively. The ratio of Ig/I is the ratio of the intensity of excimer (A 480 nm) to monomer fluorescence (A 377 nm). The ratio of I3/I1 is the ratio of the intensity of the pyrene monomer fluorescence intensity of peak 3 (A 384 nm) to peak 1 (A 373 nm). 

Recombinant and mutant (His433Tyr) L mingrelica firefly luciferases were isolated form E.coli cells and purified to homogeneity as described in. MMOL and DMOL were synthesized and kindly provided to us by Dr. D. Weiss. Absorption and fluorescence spectra of MMOL and DMOL in 0.05 Tris-acetate, containing 2 mM EDTA, 10 mM MgS04 were obtained at different pH on a Shimadzu UV 1202 spectrophotometer, and a LS 50B Perkin Elmer spectrofluorimeter, respectively. 

Instrumentation and reagents. Fluorescence experiments were recorded by a Hitachi F-4500 fluorescence spectrophotometer and Perkin Elmer 1420 multilabel counter. QDs were purchased from Invitrogen. ImmunoPure F(ab )2 Preparation Kit that is used to prepare F(ab )2, was obtained from Pierce. 

Perkin-Elmer LS55 (Perkin-Elmer, USA) fluorescence spectrophotometer The Electronic Balance (Mettler Toledo, Shanghai, China) PHS-3C digital pH-meter (Shang Hai Lei Ci Device Works, Shanghai, China). 

Optical polished Nd Lu20j transparent samples were used for the spectroscopic measurement. Linear optical transmittance of 3at.%Nd Lu203 transparent ceramic was measured in region of 190-1100 nm on a UV. VIS/NIR spectrophotometer (Lambda 2, Perkin Elmer, U.S.A.). The fluorescence spectrum of the specimen was recorded by a spectrofluorometer (Fluorolog-3, Jobin Yvon, Edision, U.S.A.) equipped with a Hamamatsu R928 photomultiplier tube. A 808nm continuous wave diode laser was used as the excitation source. 

Measurements. Steady-state absorption and emission spectra were recorded on a Perkin-Elmer 552 UV-visible and an MPF-44B fluorescence spectrophotometer, respectively. Fluorescence decay rate constants, and quenching rate constants, kgy were measured with a PRA LN-100 nitrogen laser system with fast spectroscopic detection (16, 17). Measurement of the degree of polarization (18-20) and transient absorption via laser photolysis were described in previous studies (21). 

Spectra. A Perkin-Elmer Hitachi model 200 spectrophotometer was ised to record all ultraviolet spectra. The infrared spectra of the films were obtained using a Nicolet FTIR-T199. The transmission spectra of films were obtained from samples moistened in tetrachloroethylene (2) and mounted between NaCl plates. Attennuated total reflection (ATR) spectra were taken by placing the exposed side of the film in contact with a germanium crystal at a angle of incidence. Fluorescence from film surfaces were measured using a Perkin-Elmer MPF-i iiB fluorescence spectrometer. The excitation beam (3 0 nm, slit, i+nm) was incident on the film at and the emission (iiOO-500 nm) was measured at 90 to the excitation beam. 

The spectra were not corrected for the spectral variation in the excitation source and photomultiplier tube sensitivity. Background scattered light was zeroed electronically before the acquisition of the fluorescence of 4-methylcoumaro-[222]cryptand. Absorption spectra were obtained using Perkin Elmer Lambda 7 UV/VIS Spectrophotometer. 

Steady state absorption and fluorescence measurements were made using a Perkin-Elmer 554 spectrophotometer and a Perkin-Elmer MPF-4 fluorimeter. Fluorescence lifetimes were measured using time-correlated single photon counting [5,7]. Details of the analysis of the decays can be found in [7]. 

Absorption spectra were obtained on a Pye-Unicam SP8800 spectrophotometer while fluorescence measurements were made on a Perkin-Elmer MDF44B spectrofluorometer at -196°C. 

Fluorescence measurements. Intrinsic fluorescence was determined in a Perkin-Elmer 650-40 fluorescence spectrophotometer thermostated at 30°C, using excitation and emission wavelengths of 295 and 336 nm, respectively. A buffer solution of 50 mM Hepes at pH 7 was used for enzyme desalting and for fluorescence measurements. AF is defined as Fq - F where Fq and F are the fluorescence intensity of the protein in the absence or presence of the quencher. 

UV/visible spectra and kinetic data were collected on a Perkin-Elmer 559A spectrophotometer or a Perkin Elmer Lambda 40 spectrophotometer. Product yields were determined on a Perkin-Elmer LC-235 HPLC equipped with a 235C diode-array detector measuring absorbance at A. = 220 nm and a LC 240 fluorescence detector, (ex. X = 210 nm, em X = 330 nm). The HPLC was fitted with a Rainin Microsorb-MV C-18 reverse phase column (4.6 mm ID x 25 cm 5-nm particle size) a 200 pi sample loop. The mobile phase for product separation was 80% MeOH/20% H2O with a flow rate of 0.8 ml/min for ail runs. Reported peak areas are averages of triphcate injections. Solution pH was measured with an Orion combination pH microelectrode, model 8103. a spin-lattice relaxation times, Ti, were measured on a Varian VXR-200 and... 

Perkin Elmer Model MPF-2A and MPF 44-B fluorescence spectrophotometers were used to measure fluorescence spectra of samples. The powder sample was placed in the solid sample holder attached to the instruments, which measures the reflectance fluorescence at 60° v/ith the exciting beam at 30°C to the sample surface. The samples were dried at 60°C in vacuum and kept in a desiccator containing P2O5. 

Ultraviolet-visible absorption spectra of polymers and model compounds were measured on a Beckman ACTA MVI spectrophotometer. Fluorescence spectra of compounds in dilute solution were recorded using an Aminco-Bowman spectrophotofluorometer at 20 C. Differential scanning calorimetry (DSC) was performed using a Perkin-Elmer DSC-2 scanning calorimeter. Melting points were determined on a Perkin-Elmer DSC-II at a 5 C/min. heating rate. Elemental analyses were by Galbraith Laboratories, Knoxville, Tennessee. 

The ultraviolet (UV) and visible (Vis) absorption and fluorescence spectra were measured with UV-VIS Lambda 20 Perkin-Elmer Spectrophotometer and LS-55 Perkin-Elmer fluorescence spectrometer, respectively. Both fluorescence quartz cuvettes a standard square 10 mm x 10 mm and a short path (p-cuvette) 1 mm x 10 mm, were used. The right angle fluorescence measurements geometry is shown in the Fig. 3. 

SpectrosooDy Absorption and fluorescence spectra were measured with a Cary spectrophotometer and Perkin Elmer fluorometer at 77 K with computer Interfacing as described In [Brown, Schoch 1982]. 

A Perkin-Elmer 1600 Fourier transform infrared (FT-IR) spectrometer was used for recording infrared spectra. UV spectra were obtained on a Perkin-Elmer Lambda 6 UV-Vis spectrophotometer. Corrected fluorescence spectra were obtained on a SPEX Fluorolog-2 fluorimeter with 3.5 nm bandpass... 

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