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Quattro Presentation. Part I---About Photoluminescence. About Fluorescence. The phenomenon of temporary light absorption and subsequent light emission is called Photoluminescence. The Jablonski Diagram. Absorption (10 -15 s) Internal conversion (10 -12 s)
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About Fluorescence The phenomenon of temporary light absorption and subsequent light emission is called Photoluminescence
The Jablonski Diagram • Absorption (10-15 s) • Internal conversion (10-12 s) • Intersystem crossing (heavy-atom enhanced) • Quenching by external quenchers (diffusion-controlled) • Fluorescence (10-9 s) • Phosphorescence/Inorganic luminescence (10-5 - 101 s) Kasha’s Rule: Photoluminescence always from S1 (fluorescence) or T1 (phosphorescence)
Important Characteristics of Photoluminescence • Each Photoluminescence substance has its own excitation and emission spectra. • The intensity of the Photoluminescence is proportional to its absorption, which in turn is proportional to the excitation light. • The Photoluminescence emission of a substance is always at a higher wavelength than the light used to excite the substance (Stokes-shift phenomenon). • The Photoluminescence of a substance is sensitive to many factors and will change or even disappear under different conditions.
Advantage of Using Photoluminescence as Research Tool • It is very sensitive • It allows to measure very small amount of substance in a given sample • It allows to measure very small changes • It allows to track conformational changes • It is very safe • It is very fast • It is cost-effective • It is widely used in every research
What Can be Measured of a Photoluminescence Substance • Photoluminescence intensity • Excitation spectra • Emission spectra • Photoluminescence lifetime • Anisotropy & Polarization • Time-based Photoluminescence intensity • Time-based Photoluminescence lifetime Quattro II can measure them all!
Part II---General Photoluminescence Instruments and Instruments from PTI/ OBB Family
Photoluminescence System Composition--General • Excitation • Excitation light source • Excitation wavelength selection • Optics for sample excitation • Sample holder/ compartment • Emission • Emission wavelength selection • Optics for sample emission • Detector • Computer interface • Software • Accessories & Attachments
Photoluminescence Systems from OBB/ PTI • Complete Integrated PLSystems: • Quattro • Easylife Series • FluoDia T70 High Temperature fluorescence Plate Reader • Complete open architecture design PL Systems: • QuantaMaster (QM) system for steady-state luminescence measurement • RatioMaster (RM) system for Ratiometric fluorescent measurement of microscopic samples using PMT detector(s) • Easy-Ratio Pro (ERP) system for Ratio fluorescent imaging of microscopic samples using camera as detector • TimeMaster (TM) system for Time-resolved luminescence measurement • Optical Building Blocks: light sources, monochromator, detectors, accessories, et al
Who are We? • PTI is the oldest independent photoluminescence company, specializing in manufacturing and selling complete spectroscopy systems as well as their basic building blocks globally for nearly thirty years. • The Company was established in 1983 in New Jersey, U.S.A. , where the current Headquarter is located • It has a Canadian subsidiary, where most of manufacturing is done and also offices in UK and Germany. • It has international representatives in most countries worldwide. • PTI is entirely dedicated to Photoluminescence products. • In 2007, Optical Building Blocks was established from within PTI -all Integrated Photoluminescence systems, along with optical building blocks now form the core products of Optical Building Blocks Corp., with headquarter in New Jersey, USA
Quattro • Ultra-high sensitivity: S/N > 20,000:1 using water Raman • Single-shot operation • Exceptional precision, stability and reproducibility • Very low stray-light • Super fast acquisitions: measure up to 500 complete decays in a second • Fully automated: complete spectral and lifetime characterization with one click • Easy to operate software. • Low Maintenance • Anti-photo-bleaching design • Ultra-high Sensitivity • Exceptional precision • Super fast speed • Very low stray-light • Extremely easy to use
Unmatchable Sensitivity S/N of 40000:1 measured with Water Raman here on this unit
Super Fast Acquisition Decay of Terbium: t1=422.4us (100%) Offset=-0.000014V, Chi-sq=1.13 (Auto mode, Integration: 10000 Shots at 250 HZ Obtain Decay Data within several seconds.
Optical Layout Light Source Emission Monochromator Detector Excitation Monochromator Sample Compartment
Excitation Light Source • High power pulsed xenon lamp with pre-aligned ellipsoidal reflector • Wavelength Range: 200 to 2000 nm • Pulsed Repetition rate: 1 to 500 HZ (software control ) • Pulse Width 1 µs (FWHM) • Energy per flash: up to 0.15 J • Each pulse is excitation corrected by a silicon photodiode • Lamp life time: 1 x 109 flashes - flashing only during acquisition extends the lamp life time up to 10 years with 8 hr operation per day.
Excitation Monochromator • Asymmetrical Czerny-Turner, coma corrected for minimal stray light • Focal length: 250 mm • Anti-backlashed sine-drive • Precision, two stage auto-calibration • Range: -50 to 1100 nm • Computer selectable spectral bandwidth: 1.5, 2.5, 5, 10, 20 nm slits • Throughput: 70% at 300 nm – grating blazed @ 300nm • Grating type: ruled • Grating size: 50 x 50 mm • Grating groove density: 1200 lines/mm • Apertures: input - f/3.3; output - f/3.7 • Reciprocal linear dispersion: 3.3 nm/mm • Stray light: <0.005% 20 nm away from 632.8 nm Helium Neon line • Accuracy: ±0.2 nm • Optical resolution: 1.5 nm • Maximum scanning speed: 50 nm/sec
Excitation Correction • RCQC: • Type: Enhanced silicon photodiode • Gain: 1 to 1250 times • Linearity: Linear for the entire range of gain values • Range: 200 – 1100 nm • Calibration at factory: 250 – 600 nm vs. rhodamine White: a lamp scan without excitation correction; Red: Same scan with excitation correction activated. Conclusion: standard deviation is better than 0.6 % (260 – 600 nm)
Sample Compartment • Standard Peltier thermo-electrical temperature controlled 3-window cuvette holder: 10° -70° C • Standard Variable speed magnetic stirrer • Aberration corrected demagnified optics result in a light spot <500 um at the sample. • Sample light collection solid angle: 40 • Beam splitter reflects a fraction of the excitation beam to a RCQC (Reference Channel Quantum Counter) photodiode to monitor fluctuations in the excitation beam, both temporal and wavelength. • Double sets of excitation and emission filter holders accommodate 1 inch. diameter round filters • Gas purgeable compartment
Temperature Controlled Sample Holder • Temperature ranges: 10 – 70 °C (nitrogen purging is required when <15°C) • Maximum temperature ramping speed: 20 °C per min (0.33°C/ sec) • Accuracy: ±0.1 °C • Temperature settings resolution: 10 bit (0.06°C) • Temperature stability (after settling): 0.1°C • Water cooled heat sink.
Emission Monochromator • Asymmetrical Czerny-Turner, coma corrected for maximal throughput • Focal length: 250 mm • Anti-backlashed sine-drive • Precision, two stage auto-calibration • Range: -50 to 1100 nm • Computer selectable spectral bandwidth: 1.5, 2.5, 5, 10, 20 nm slits • Throughput: 70% at 500 nm – grating blazed @ 500nm • Grating type: ruled • Grating size: 50 x 50 mm • Grating groove density: 1200 lines/mm • Apertures: input - f/3.7; output - f/3.7 • Reciprocal linear dispersion: 3.3 nm/mm • Stray light: <0.015% 20 nm away from 632.8 nm Helium Neon line • Accuracy: ±0.2 nm • Optical resolution: 1.5 nm • Maximum scanning speed: 50 nm/sec
Detector • Detector: DC Electrical Coupling, • Typical wavelength range 185-650nm • Optional: 185-900 nm • Instrument Response: 6 μs
Instrument Response Function Digitizing: 0.8 us/ point (Fastest) Xe Lamp flash (FWHM): 1.1 us PMT and electronic amplifier response (FWHM): 6 usec Minimum lifetime: 50 usec (Auto Mode). 10 usec. (Manual mode)
Emission & Excitation Correction White: synchronous scan of a lamp without excitation and emission correction ; Green: Same scan with excitation and emission correction activated. Conclusion: standard deviation of synchronous scan is better than 8 % (over Teflon diffuser)
Software and Electronics • Real time digital signal filtering (user selectable) • Transient digitizer acquisition sampling rate: 1.25 Ms/s (0.8 ms/data point) • Digitizing: 16 bits • FluoreScan software • All acquisitions are selected from the main screen of the software. • One click “water Raman” test to confirm system sensitivity • Automatic identification and optimization of excitation and emission wavelengths for unknown samples. • Multiple lifetime fitting 1 to 4 exponentials. • Life times decays can be plotted in real time with automatic exponential fitting
Analysis • Automatic Analysis features can be applied in real time: • Digital filtering, • Automatic multi-exponential fitting. • Math and curve process functions: • Normalize, average, Integrate, differentiate • Multi peak finder, smooth • 3D peak finder • Automatic water Raman calculation
Options • Rotatable solid sample holders • Rotatable powder sample holders • Polarizers • Filters (Long pass, bandpass, neutral Density filters) • Semi-micro cuvette
Data Acquisition • Phosphorescence decay with instant lifetime calculation (up to 4) • Time-based lifetime scan • Anisotropy decay (rotational correlation times) • Lifetime temperature ramping • 3-D excitation vs. decay vs. intensity • 3-D emission vs decay vs intensity • Corrected excitation/ Emission spectra • Time-based intensity scans • Polarization (anisotropy) excitation and emission spectra • Synchronous scans • Intensity vs temperature ramping • 3-D excitation/ emission mapping (EEM): Excitation vs emission vs intensity
Automatic Calibration • FluoreScan has four auto calibration procedures: • Excitation monochromator: for excitation wavelength calibration • Emission monochromator: for emission wavelength calibration • PMT: automatic calculate best HV for the PMT detector for each sample • RCQC: automatic calculate best HV for the detector used for real-time correction for each sample
3D Display Real time 3D scan of DYAG : Slits are 2.5 nm; repetition is 250 Hz; HV is 1000V
Applications • Lanthanide-based assays development • LRET based assays • Room temperature phosphorescence of micelle-stabilized aromatics • Room temperature phosphorescence of organics on solid substrate • Optical sensor for carbon dioxide. • Assay for clostridial toxin activity • DNA hybridization assay • Luminescence-based molecular beacons • General steady state fluorescence and phosphorescence • Phosphorescence lifetimes • Inorganic crystals, semiconductors and doped glasses • Protein-protein Interactions • Protein-peptides interactions • Protein folding-unfolding • Membrane Studies • Photosynthesis • Room temperature phosphorescence of proteins (Trp)
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