WO2000014515A9 - Low frequency modulation sensors using nanosecond fluorophores - Google Patents
Low frequency modulation sensors using nanosecond fluorophoresInfo
- Publication number
- WO2000014515A9 WO2000014515A9 PCT/US1999/020370 US9920370W WO0014515A9 WO 2000014515 A9 WO2000014515 A9 WO 2000014515A9 US 9920370 W US9920370 W US 9920370W WO 0014515 A9 WO0014515 A9 WO 0014515A9
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- fluorophore
- sample
- modulation
- analyte
- light
- Prior art date
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6408—Fluorescence; Phosphorescence with measurement of decay time, time resolved fluorescence
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6408—Fluorescence; Phosphorescence with measurement of decay time, time resolved fluorescence
- G01N2021/6415—Fluorescence; Phosphorescence with measurement of decay time, time resolved fluorescence with two excitations, e.g. strong pump/probe flash
Definitions
- phase angles or decay times rather than intensities are advantageous because decay times are mostly independent of the signal level and can be measured in turbid media and even through skin (Bambot et al., 1995; Szmacinski and
- LEDs blue and UV light emitting diodes
- modulation sensing can be accurate even if the overall signal level changes due to flexing in fiber optics or changes in the positioning of the sample.
- the calibration curves for a modulation sensor will change if the sensing and reference fluorophore photobleach at different rates.
- LEDs are available within a range of output wavelengths, even down to the near UV at 390 nm (Sipior et al., 1997). LEDs consume little power and can easily be driven by batteries.
- the modulation sensor could be a small device held near the skin.
- the long- lifetime complex can be part of the device, so none of the long-lifetime probe enters the sample or tissue.
- the high chemical and photochemical stability of the metal-ligand complexes suggests the signal from the long lifetime reference will be constant for long periods of time. Hence, such devices may prove valuable for quantitation of intrinsic and extrinsic fluorophores in tissues.
- modulation sensing may be the expanded range of analytes. Any sensing fluorophore which changes intensity can be used in this model.
- modulation sensing can be used with probes such as a sodium-binding benzofuran isophthalate (SBFI) and a potassium-binding benzofuran isophthalate (PBFI), which are poor wavelength-ratiometric probes for sodium and potassium.
- SBFI sodium-binding benzofuran isophthalate
- PBFI potassium-binding benzofuran isophthalate
- Described here is a new method which allows quantitative measurements of fluorescence intensity with simple instrumentation.
- the method is self-calibrating related to a reference fluorophore.
- the method can also be used in highly scattering media.
- the measurement principle is based on observing the emission from both the fluorophore of interest with a ns decay time and of a reference fluorophore which displays a much longer microsecond lifetime.
- the reference fluorophore is placed on rather than in the sample to mimic a sensing device with the long lifetime reference held against the skin.
- the amplitude modulation of the emission is observed using the standard method of frequency-domain fluorometry. At an intermediate modulation frequency, the modulation is equivalent to the fractional intensity of the ns fluorophore.
- the method was tested in 0.5% intralipid, which is more highly scattering than skin. Quantitative intensity measurements were obtained for various concentrations of fluorescein in intralipid, and of the pH sensor 6-carboxy fluorescein. Low frequency modulation measurements provide a general method for quantitative measurements in the presence of factors which preclude direct intensity measurements, or applications which require simple internally referenced measurements.
- Figure 1 is a schematic of a portable modulation intensity sensor.
- Figure 2 shows emission spectra of fluorescein in 0.5% intralipid. Excitation at 488 nm. The dashed line shows the transmission curve of the emission filter. Emission for [Ru(bpy) 3 ] 2+ in the
- FIGS. 3 A and 3B are schematics of sensors with a ns fluorophore and [Ru(bpy) 3 ] 2+ .
- Figure 4 shows emission spectra of the model sensor containing fluorescein in the internal aqueous phase and [Ru(bpy) 3 ] 2+ in an external PVA film.
- Figure 5 shows the frequency-domain intensity decay of the fluorescein- [Ru(bpy) 3 ] 2+ model sensor.
- Figure 6 shows emission spectra of a pH sensor based on a mixture of 6-carboxyfluorescein (6-
- Figure 7A shows the frequency response of the pH sensor and Figure 7B shows the low frequency modulation of the pH sensor.
- Figure 8 shows a calculation curve of the pH sensor.
- Figure 9 shows emission spectra of a modulated calcium sensor based on Fluo-3 and
- Figure 10 shows a modulation frequency response of the calcium sensor.
- Figure 11 shows phase angle frequency response of the calcium sensor.
- Figures 12A and 12B show phase and modulation calibration curves of the calcium sensor.
- Figures 13A and 13B show frequency-domain intensity decay of the intralipid sample containing fluorescein.
- the cuvette did not have the external [Ru(bpy) 3 ] 2+ -PVA film.
- Figure 14 shows a frequency response of the fluorescein-[Ru(bpy) 3 ] 2+ -intralipid sample shown in Figure 1.
- Figure 15 shows low frequency modulation of the fluorescein- [Ru(bpy) 3 ] 2 ⁇ intralipid sample shown in Figure 2.
- Figure 16 shows modulation versus fluorescein concentration.
- Figure 17 shows emission spectra of 6-carboxy fluorescein in 0.5% intralipid.
- the experimental arrangement is similar to that shown in Figure 2, including the long-lifetime standard.
- Figures 18A and 18B show the frequency response of the 6-carboxy fluorescein-[Ru(bpy) 3 ] 2+ - intralipid sample shown in Figure 6.
- the bottom panel shows the low frequency modulation on an expanded scale.
- Figure 19 shows modulation versus pH calibration curve for 6-CF in 0.5% intralipid.
- Figures 20A-L show representative fluorophores which are not sensitive to analytes.
- Described here is a general method to perform sensing at low light modulation frequencies near 1 MHz using sensing fluorophores with ns lifetimes, without relying on a change in lifetime of the ns fluorophore.
- the basic idea is to use a mixture of the ns fluorophore with a fluorophore which displays a long lifetime near 1 ⁇ s.
- the modulation of the emission at intermediate frequencies becomes equivalent to the fraction of the total emission due to the short lifetime ns fluorophore. This occurs because the emission from the ⁇ s fluorophore is demodulated, and that of the ns fluorophore is near unity.
- This methods allows sensing based on modulation from about 1 to 10 MHz. Additionally, the ns sensing fluorophore does not need to display a change in lifetime. A simple change in intensity in response to the analyte is adequate for a low frequency modulation sensor.
- Abbreviations used in this disclosure are: PVA - polyvinyl alcohol; bpy - 2,2'-bipyridyl; 6-CF - 6-carboxyfluorescein; FD - frequency domain; BCECF is 2',7'-b 5(2-carboxyethyl)-5(and 6)-carboxyfluorescein; [Ru(bpy) 2 (dcbpy)] 2+ is Bis(2,2'-bipyridine)(2,2'-bipyridine-4,4'- dicarboxylic acid)ruthenium(II); C. is carboxy; SNAFL is seminaphtofluorescein; and SNARF is seminaphtorhodafluor.
- the methods described herein allow measurement of many analytes. These include, but are not limited to, H + , pH, Na + , K + , Li + , Mg 2+ , Ca 2+ , Cl " , HC0 3 CO,, 0 2 , glucose, lactate, antigens and drugs.
- a large number of different fluorophores can be used as the sensing fluorophores and as the long lifetime fluorophores.
- Analyte sensing fluorophores include, but are not limited to, Quin-2, Fura-2, Indo-1, Calcium Green, Calcium Orange, Calcium Crimson and Benzoxazine-crown which are useful as Ca 2+ probes; Mag-Quin-2, Magnesium Green, and Benzoxazine-crown as Mg 2 probes; PBFI as a K + probe, Sodium Green as a Na + probe, and SNAFL-1, C. SNAFL-1, C. SNAFL-2, C. SNARF- 1, C. SNARF-2, C. SNARF-6, C. SNARF-X, BCECF, and Resorufm Acetate as pH probes.
- Probes for Cl " include 6-methoxy-N- ethylquinolinium chloride; N-(6-methoxyquinolyl)acetoethyl ester; 6-methoxy-N- ethylquinolinium chloride; 6-methoxy-N-(3-trimethylammoniumpropyl)quinolinium dibromide; 6-methoxy-N-(3-trimethylammoniumpropyl)phenanthrindium dibromide; and 6-methoxy-N-(4- aminoalkyl)quinolinium bromide hydrochloride.
- the above fluorophores are described in Szmacinski and Lakowicz, 1994a.
- chloride probes include 6-methoxy-N-(3- sulfoproxyl)quinolinium; N-sulfopropylacridinium; N,N-dimethyl-9,9'-bisacridinium nitrate; N- methylacridinium-9-carboxamides; and N-methylacridinium-9-methylcarboxylate.
- Additional probes useful for measuring pH include 8-hydroxypyrene-l,3,6-trisulfonate; [Ru(4,4'- diethylaminomethyl-2,2'-bipyridine)(2,2'-bipyridine) 2 ] 2+ ; Oregon Green, DM- ⁇ ERF and Cl- ⁇ ERF.
- Additional fluorophores sensitive to Mg 2+ include Mag-Quin-1; Mag-Fura-2; Mag-Fura- 5, Mag-Indo-1 ; Mag-Fura-Red; and Mg Orange.
- Additional fluorophores sensitive to ⁇ a + include sodium-binding benzofuran isophthalate and sodium-binding benzofuran oxazole.
- Additional fluorophores sensitive to K + include CD222. Additional fluorophores sensitive to Ca 2+ include Fura Red; BTC (coumarin benzothiazole-based indicator); Fluo-3; Rhod-2; Ca Green-2; Ca Green-5N; Ca Orange-5N; Oregon Green - BAPTA-1, BAPTA-2 and BAPTA-5N. These additional analyte sensitive fluorophores are discussed in Lakowicz, 1999. Fluorophores which are not sensitive to the analyte being tested but are used in conjunction with the analyte sensitive fluorophores include, but are not limited to, the compounds shown in Figures 20A-L.
- a binding agent labeled with a fluorophore such that the binding agent binds specifically to the analyte.
- a glucose-binding protein, a glucose-galactose binding protein, or concanavalin A can be used in a method to measure glucose.
- a lactate binding protein can be used for measurement of lactate.
- Antibodies or antibody fragments can be used to measure drugs or antigens.
- Other binding agents known to those of skill in the art can also be used.
- Fluorescence is defined as meaning fluorescence, phosphorescence, luminescence or mixed-state emissions. This method is based on measurement of the modulation of the emission when the sample is excited with amplitude modulated light. In this method, the emission of the scattering sample is observed along with the emission of a long lifetime reference fluorophore.
- the reference fluorophore need not be within the sample, but can be on the surface outside the sample. This geometry is useful for sensing devices in which the long lifetime reference is held against the skin.
- the light modulation and measurement frequency is chosen so that the emission from the long-lifetime reference is completely demodulated. Under these conditions, the intensity of the fluorophore of interest with a ns decay time is given by the modulation of the total signal.
- This method can be applied to any sample which displays changes in intensity, or any sensing fluorophore which shows intensity changes due to its response to an analyte of interest.
- This method can be used with a hand-held instrument for point-of-care transdermal measurements.
- the method can be performed on a variety of systems or samples, including in vivo, blood plasma, whole blood, saliva, any body fluid, tissue culture, a sample from an aquarium, etc.
- the method may be used to monitor a bioprocessing reaction, industrially, in process control, as part of an analytical chemistry process, etc.
- the incident light can be produced by, but is not limited to, a laser, a light emitting diode (LED) or an electroluminescent light source (ELL). Intensity decays were measured using the frequency-domain method. This method and procedure for data analysis have been described in detail (Lakowicz and Gryczynski, 1991; Lakowicz, in press; Lakowicz et al, 1984; Gratton et al., 1984; Lakowicz and Gryczynski, 1991).
- ⁇ and the Yf. are constrained to be equal to unity
- ⁇ and the Yf. are constrained to be equal to unity
- f. is the fractional intensity
- ⁇ is the phase angle
- m is the modulation of each fluorophore.
- the modulation of the emission is the fractional intensity of the short lifetime component.
- the short lifetime fluorophores were selected to display changes in intensity in response to the analyte.
- the long lifetime fluorophore is [Ru(bpy) 3 ] 2+ , and is not sensitive to changes in pH or calcium over the investigated concentration ranges. Measurements of nanosecond and subnanosecond lifetimes in scattering media can be affected by the time-dependent migration of photons due to the multiple scattering events.
- the subscript c indicates calculated values for assumed parameter values.
- ⁇ and ⁇ m are the uncertainties in the phase and modulation data, respectively, and ⁇ is the number of degrees of freedom.
- the present invention is further detailed in the following Examples, which are offered by way of illustration and are not intended to limit the invention in any manner. Standard techniques well known in the art or the techniques specifically described below are utilized.
- Disodium fluorescein was from Exciton, Inc. Intralipid (20%) was obtained from Kabi Vitrum, Inc. and diluted 40-fold to 0.5%. Water was deionized with a Milli- Q purification system. Solutions ranging from pH 5.0 to 9.1 were prepared in 50 mM TRIS buffer for the 6-carboxyfluorescein studies. Experiments using the Ca 2+ indicator Fluo-3 were performed solely in plastic media to prevent uptake of Ca 2+ from glass surfaces. All solutions were prepared in plastic vials from the calcium calibration buffer. Luminescence measurements were performed in polystyrene plastic cuvettes.
- Ru(bpy) 3 Cl 2 was in a polyvinyl alcohol film on the outside of the cuvette.
- a small aliquot of aqueous Ru(bpy) 3 Cl 2 6H 2 O was added to solutions containing the nanosecond fluorophore (6- carboxyfluorescein or Fluo-3) with analyte.
- the steady-state emission intensity of Ru(bpy) 3 Cl 2 6H 2 O contributed about 20-30% of the total sample intensity at the highest pH (6-carboxyfluorescein) or at the highest Ca 2+ concentration (Fluo-3).
- UV-Vis absorption spectra were measured on a Hewlett Packard 8453 diode array spectrophotometer with ⁇ 1 nm resolution. Uncorrected steady-state emission spectra were obtained on a SLM AB-2 fluorimeter under magic angle polarization conditions. Time-resolved luminescence decays were measured in the frequency domain (ISS, Koala) using an air cooled cw-Ar + laser (Omnichrome, 543-AP) operating at 488.0 nm (80 mW) as the excitation source. The 488 nm output was amplitude modulated using an electro-optic modulator, which provided modulated excitation from 300 kHz to 150 MHz. This frequency-domain instrument was comparable to those described previously (Gratton and Limkeman, 1983; Lakowicz and Maliwal, 1985).
- the laser was passed through a Pockels cell which provided modulated light from 300 kHz to 150 MHz.
- Two different PTS frequency synthesizers (PTS-500) were used to modulate the Pockels cell and detection system.
- the output of the PTS synthesizer driving the Pockels cell was amplified by an ENI 25 W linear RF amplifier (325 LA, 250 kHz - 150 MHz) prior to Pockels cell input.
- the other PTS synthesizer output was directed into an ENI 3W linear RF amplifier (403 LA, 150 kHz-300 MHz) for proper modulation of the detection system.
- the emission was observed as usual at 90° to the excitation through an appropriate combination of long-pass filters which eliminated scattered light at the excitation wavelength. We used this experimental configuration because it was available in this laboratory. In the actual use of modulation sensing we expect the light source will be an intensity modulated LED or some other solid state light source.
- ⁇ and the Yf, are constrained to be equal to unity.
- Rhodamine B in water with a lifetime of 1.68 ns was used as a lifetime reference in the frequency-domain experiments (Gryczynski et al., 1997).
- Luminescence decays were analyzed by non-linear least squares procedures described previously (Lakowicz et al., 1984; Gratton et al., 1984).
- Global analysis of frequency-domain emission decay data was performed with programs developed at the Center for Fluorescence Spectroscopy. In the global analysis, the lifetimes were the global parameters and the amplitudes were fitted as non-global parameters. This means that the lifetimes were fitted parameters, but were constrained to be the same values at all analyte concentrations or all pH values for 6-CF. The amplitudes were also fitted parameters, but were allowed to vary at each analyte concentration or pH value.
- Figure 5 shows the frequency-domain intensity decays of this model assay.
- the emission is already demodulated below 1.0 for the lowest measurement frequency near 1.8 MHz. This effect is due to the long decay time of [Ru(bpy) 3 ] 2+ in PVA.
- the decay time of [Ru(bpy) 3 ] 2 " in PVA was found to be 1180 ns.
- the modulation is nearly constant from 2 to 8 MHz. This occurs because the modulation of [Ru(bpy) 3 ] 2 " is near zero, and that of fluorescein with a lifetime of 2.85 ns is near 1.0. In this low frequency range the modulation is expected to represent the fractional steady state intensity of the short lifetime emission (eq. 13).
- Comparison of Figures 4 and 5 shows that the modulation values at intermediate frequencies are approximately equal to the intensity of fluorescein relative to that of [Ru(bpy) 3 ] 2 ⁇
- 6-carboxyfluorescein 6- CF
- Fluorescein and its derivatives have been widely used for pH sensing (Thomas et al., 1979; Babcock, 1983; Klonis et al., 1998). Fluorescein and its derivatives display a pH-dependent dissociation of the carboxyl group. The ionized form which exists at pH values above 7.5 is highly fluorescent, and the protonated low pH form is essentially non-fluorescent. For this reason fluorescein is not known to display a change in lifetime when this dissociation reaction occurs.
- Frequency-domain intensity decay data for the mixture of 6-CF and [Ru(bpy) 3 ] 2+ are shown in Figure 7A.
- the frequency data were analyzed using the multi-exponential model (eq. 1). At all pH values the frequency responses could be fit to two decay times of 4.0 and 370 ns, as can be seen from the global analysis in Table I. As the pH value increases the fractional steady state intensity of the short component (f f ) also increases.
- the pH values are typically accurate to ⁇ 0.02 or better (Mahutte et al, 1994a; Mahutte et al., 1994b; Shapiro et al., 1993 ; Mahutte, 1994).
- the present sensor was found to be sensitive to changes in pH of ⁇ 0.1, as can be seen in the modulation data on an expanded scale (Figure 7B). For instance, pH values of 6.4 and 6.5 are easily distinguishable. Such data can be used to prepare a calibration curve for pH based on the modulation at 3.7 MHz ( Figure 5). Modulation measurements are readily accurate to ⁇ 0.007, which results in a pH accuracy of ⁇ 0.1 ( Figure 8). These results were obtained without optimizing the assay based on the relative intensities of the two species, and the overall change in intensity of the pH-sensitive fluorophore. Inclusion of measurements of the phase angle and modulation at more than one frequency will improve the pH accuracy.
- EXAMPLE 5 A MODULATION SENSOR FOR CALCIUM Calcium is known to be an intracellular messenger. Measurements of calcium concentrations have been the subject of numerous publications (Nuccitelli, 1994; Grynkiewicz et al., 1985). Calcium can be measured using intensity-ratiometric probes (Tsien et al., 1985;
- Fluo-3 cannot be used as wavelength-ratiometric or lifetime sensor for calcium, it can be used in our method of modulation sensing. This is shown in Figure 9.
- both Fluo-3 and [Ru(bpy) 3 ] 2+ were contained within the cuvette.
- the emission of Fluo-3 at 510 nm increases dramatically in the presence of Ca 2+ .
- the emission intensity of [Ru(bpy) 3 ] 2+ is not sensitive to calcium and is the same at all calcium concentrations.
- the frequency-dependent modulation of the Fluo-3 [Ru-(bpy) 3 ] 2+ mixture are shown in Figure 10. As the calcium concentration increases so does the modulation from 2 to 30 MHz.
- the phase angles show a maximum near 1 MHz. The largest values near 1 MHz are seen in the absence of calcium, where the emission is dominated by the long lifetime Ru complex. As the calcium concentration increases the phase angles decrease to smaller values as the emission becomes dominated by the shorter lived emission from Fluo-3.
- phase angles are sensitive to lower concentrations of calcium, with an apparent K D near 40 nM. This suggests the combined use of both the phase and modulation data to allow measurement of calcium over an extended range of concentrations, or to provide increased accuracy over a critical range of concentrations.
- Figure 14 shows frequency-domain measurements of the emission due to both fluorescein in intralipid and the long-lifetime reference. These data were analyzed globally using equations 14-18 (Table III). The long-lifetime of 1575 ns is essentially equivalent to that observed for [Ru(bpy) 3 ] 2+ alone in the PVA film. The lifetime of 3.89 ns is assigned to fluorescein.
- the modulation data over the range of frequencies is shown on an expanded scale in Figure 15. One notices a region from 0.3 to 8 MHz over which the modulation is nearly independent of the light modulation frequency.
- EXAMPLE 7 pH SENSING IN INTRALIPID Another use of modulation sensing is for measurement of the intensity of a sensing fluorophore in tissues or through skin. This was examined using 6-carboxy fluorescein.
- Fluorescein and its derivatives are well known to display intensities which depend on pH and dissociation of the carboxyl group (Thomas et al., 1979; Babcock, 1983; Klonis et al., 1998).
- the ionized form which exists at pH values above 7.5 is highly fluorescent, and the protonated low pH form is essentially non-fluorescent.
- pH values are typically accurate to +/- 0.02 (Shapiro et al., 1993; Mahutte et al., 1994a; Mahutte, 1994). Optimization of the method will improve the accuracy of the method for such clinical applications.
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US09/786,627 US6806089B1 (en) | 1998-09-08 | 1999-09-08 | Low frequency modulation sensors using nanosecond fluorophores |
AU61365/99A AU6136599A (en) | 1998-09-08 | 1999-09-08 | Low frequency modulation sensors using nanosecond fluorophores |
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WO2003020725A1 (en) * | 2001-08-31 | 2003-03-13 | Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyujo | Coumarin compounds |
WO2004044557A2 (en) * | 2002-11-12 | 2004-05-27 | Argose, Inc. | Non-invasive measurement of analytes |
WO2005065241A2 (en) | 2003-12-24 | 2005-07-21 | Argose, Inc. | Smmr (small molecule metabolite reporters) for use as in vivo glucose biosensors |
US7815854B2 (en) * | 2004-04-30 | 2010-10-19 | Kimberly-Clark Worldwide, Inc. | Electroluminescent illumination source for optical detection systems |
WO2006009910A2 (en) | 2004-06-17 | 2006-01-26 | The Regents Of The University Of California | Time-resolved optometric fluorescence detection for skin diagnostics |
CN100346154C (en) * | 2004-09-24 | 2007-10-31 | 湖南大学 | Method for producing internal reference nano PH sensor and using for in-cell PH non-trauma monitoring |
EP2502628B1 (en) | 2006-06-23 | 2016-12-14 | Alethia Biotherapeutics Inc. | Polynucleotides and polypeptide sequences involved in cancer |
MX336869B (en) | 2008-11-03 | 2016-02-04 | Alethia Biotherapeutics Inc | Antibodies that specifically block the biological activity of a tumor antigen. |
KR101993259B1 (en) | 2011-03-31 | 2019-06-27 | 에이디씨 테라퓨틱스 에스에이 | Antibodies against kidney associated antigen 1 and antigen binding fragments thereof |
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US5448992A (en) * | 1992-12-10 | 1995-09-12 | Sunshine Medical Instruments, Inc. | Method and apparatus for non-invasive phase sensitive measurement of blood glucose concentration |
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