Contrast medium for near infrared diagnosis

Drug – bio-affecting and body treating compositions – In vivo diagnosis or in vivo testing – Diagnostic or test agent produces in vivo fluorescence

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C424S001110, C424S001650, C424S009100, C548S100000, C548S146000

Reexamination Certificate

active

06319488

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to colloidal systems charged with polymethine dyes, their use as a contrast medium in fluorescence and transillumination diagnostics in the near infrared spectral range, as well as methods for their production.
BACKGROUND OF THE INVENTION
As biological tissue has relatively high permeability for long-wave light in the range of 700 to 1000 nm, a diagnostician can therefore use a completely different method of tissue imaging in addition to advanced medical imaging techniques such as X-raying, magnetic resonance tomography, or ultrasonic diagnosis.
Tissue-specific information can be obtained both by detecting the non-absorbed portion of radiation by means of a transmission image, and by detecting fluorescence radiation emitted after exposing the tissue to light in the near infrared range.
The main problem with the use of near infrared radiation is the extraordinarily wide scattering of light, which yields only a rather blurred image of a clearly contoured object despite different photophysical properties of such an object and its environment. This problem intensifies the greater the distance from the surface and may be considered the major limiting factor of both transillumination and the detection of fluorescence radiation.
SUMMARY OF THE INVENTION
Suitable fluorescent dyes that accumulate in diseased tissue (particularly in tumours) and display a specific absorption and emission behaviour may contribute towards enhancing the distinction of healthy from diseased tissue. The change in the irradiated (scattered) light caused by absorbtion of the dye, or fluorescence induced by exciting radiation, is detected and provides the actual tissue-specific information.
Until now, photosensitizers designed for use in photodynamic therapy (PDT) (including porphyrins, chlorines, phthalocyanines, naphthalocyanines) have been used for localizing and visualizing tumours (Bonnett R.
New photosensitizers for the photodynamic therapy of tumours
. SPIE Vol. 2078, 1994). The classes of compounds listed here share the disadvantage that in the wavelength range of 600 to 1200 nm they are either not absorbing at all or to a very little extent only. The photosensitizing effect of these dyes is disturbing for purely diagnostic uses where no effects are desired. Furthermore, photostability of the dyes listed here often is quite low.
In contrast to this, the absorption and fluorescent behaviour of dyes from the class of polymethines is characterized by high absorption coefficients in the range between 700 and 1000 nm and a sufficient fluorescent quantum yield. The photosensitizing effect of polymethines can be neglected, and most of them are highly photostable.
A clear change in the pharmacokinetic properties of fluorescent dyes may be achieved by transforming them into colloidal systems. As a result, a tissue or organ-specific, or location-specific accumulation of the fluorescent dyes formulated in this way may be achieved.
Furthermore, the dyes must be strongly hydrophilic to be applied in an aqueous solution so that sufficient quantities of dye for imaging can be introduced into the body using a water solution.
It is known that the transformation of dyes into colloidal systems may increase the applicable dose.
It is an object of this invention to provide a contrast medium that accumulates to a considerable extent in the tissues to be examined and can be detected in said tissues using near infrared radiation.


REFERENCES:
patent: 3916069 (1975-10-01), Tiers et al.
patent: 5494793 (1996-02-01), Schindele et al.
patent: 266196 (1988-05-01), None
patent: 266195 (1998-05-01), None
patent: 89/10758 (1989-11-01), None
patent: 92/07036 (1992-04-01), None
patent: 95/08772 (1995-03-01), None
patent: 96/17628 (1996-06-01), None
Kitchell et al, 1985, Methods in Enzymology, vol. 112, pp. 436-449, Poly(lactic/glycolic acid) Biodegradable Drug-Polymer Matrix Systems.*
Riefke et al, 1996, SPIE Proceedings, vol. 2927, pp. 199-208, “In vivo characterization of Cyanine dyes as contrast agents for near infrared imaging”.*
Beuthan et al, 1993, IR-Diaphanoscopy in Medicine, Medical Optical Tomography: Functional Imaging & Monitoring, vol. ISii, pp. 263-282.*
Scholes et al, Journal of Controlled Release, 25, pp. 145-153, The preparation of sub-200nm poly(lactide-co-glycolide) microspheres for site-specific drug delivery, 1993.*
Sanchez et al, European Journal of Pharmaceutics and Biopharmaceutics, vol. 41, No. 1, pp. 31-37, “Poly (D,L-lactide co-glycolide) Micro and Nano-spheres as a way to prolong Blood Plasma Levels of Subcutaneously Injected Cyclosporin A”, 1995.*
Shen et al, Makromol. Chem., Rapid Commun., vol. 14, pp. 457-460, “Synthesis and characterization of poly DL-lactic acid/glycolic acid”, 1993.*
Kohso et al, Endoscopy, vol. 22, pp. 217-220, “An investigation of an infrared Ray Electronic Endoscope with a Laser Diode Light Source”, 1990.*
Ballai et al, Cancer Immunol. Immunother. vol. 41, pp. 257-263, “Tumor labeling in vivo using cyanine-conjugated monoclonal antibodies”, 1995.*
Deligeorgiev et al, Dyes and Pigments, vol. 12, No. 2, pp. 157-162, “Near Infrared Absorbing Pyrylium Trimethine cyanine Dyes”, 1990.*
Gadjev et al, Dyes and Pigments, vol. 14, No. 1, pp. 73-77, “Near-Infrared Absorbing Asymmetrical Trimethine Cyanine Dyes”, 1990.*
Gadjev et al, Dyes and Pigments, vol. 17, No. 2, pp. 153-162, “Near Infrared Absorbing Asymmetric Trimethine Cyanine Dyes Containing BenZ [c,d] indolium and Pyrylium End Groups”, 1991.*
Kuramoto et al, Dyes and Pigments, vol. 11, pp. 21-35, “Synthesis and Characterization of Deep-Coloured Squarylium Dyes for Laser Optical Recording Media”, 1989.*
Terpetschnig, et al, Analytica Chimica Acta, vol. 282, pp. 633-641, Synthesis, spectral properties and photostabilities of symmetrical and unsymmetrical squaraines; a new class of fluorophores with long-wavelength excilation and emmision, 1993.*
Kuramoto, JSDC, vol. 106, pp. 181-186, The role of excited singlet molecular oxygen in the photodegradation of functional squarylium dyes, 1990.*
Slominskii et al, Ukrainskii Khimicheskii Zhurnal, vol. 40, No. 6, pp. 625-629, “Tricarbocyanines with Hydrocarbon Rings in the Chromophore”, 1974.*
Makin et al, Organic Chemistry, vol. 23, No. 10, Part I, pp. 1850-1852, Chemistry of Enol Esters.LXXIX. Reaction of Glutaconaldehyde acetals and their derivatives with heterocyclics Compounds The Synthesis of Tricarbo-cyanine Dyes, 1987.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Contrast medium for near infrared diagnosis does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Contrast medium for near infrared diagnosis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Contrast medium for near infrared diagnosis will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2574108

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.