Photosensitizing agent

Rectified oils have been redistilled to improve a particular property or characteristic, such as flavor or aroma. Eor example, natural oil of peppermint is frequently rectified to remove dimethyl sulfide, which has a powerful and objectionable cooked vegetable note deleterious to the use of the oil in cmme de menthe Hqueurs. Distillation is also used to remove psoralens, which are harmful photosensitizing agents present in natural bergamot oil. Color may be removed, eg, from cassia oil, by vacuum steam distillation. A desirable component, such as 1,8-cineole (eucalyptol) 85% in eucalyptus oil, may be... 

The related antibacterial oxolinic acid (340, pKa 6.9) also photosensitized singlet oxygen production in either of its ionized forms. As oxolinic acid seemed not to be very phototoxic, it was concluded that free radicals were the most potent photosensitizing agents from nalidixic acid and some other drugs. 

Hypericin from St. John s wort is another phenolic compound with multiple rings and multiple double bonds. This compound readily absorbs UV light and is a primary photosensitizing agent that will result in severe sunburn in species that either ingest the plant or come in contact with plant dust or leaf extracts. 

Larson. R.A.. Stackhouse. P.L., and Crowley. T.O. Riboflavin tetraacetate a potentially useful photosensitizing agent for the treatment of contaminated waters. Environ. Sci TechnoL, 26(9) 1792-1798, 1992. 

Each material was free radically polymerized and provided photosensitive agents useful in photolithography using ArF excimer lasers. Other alkaline-susceptible 1,1,1,3,3,3-hexafluoroisopropy resins containing ester and acetal substituents have been prepared by this group were effective in the 157-nm range in earlier investigations. 

Linear furanocoumarins are polenl photosensitizing agents in celery, parsley, parsnips, limes, and figs. The most commonly reported symptoms include contact dermatitis and photodermatitis. particularly on the hands and forearms. 

The Step 2 product was spin-coated onto a silicone wafer and baked for 2 minutes at 215°C. Thereafter the anti-reflective mixture was coated with a Keum Ho petroleum photosensitive agent and baked for 90 seconds 110°C. After these processes the material was exposed to a light source by means of ASML/900 scanner apparatus and baked an additional 90 minutes at 130°C. The exposed wafer was developed using an aqueous solution of 2.38% tetramethyl-ammonium hydroxide. 

A photosensitive agent, (VI), used as a lithographic printing plate was prepared by Matsumura [5] as a method for improving image resolution and print quality. 

Utility Therapeutic Photosensitizing Agents in the Treatment of Tumors... 

Many substances of this type, produced by co-oligomerization, are known and have a wide variety of important commercial uses (e.g., medicines and photosensitizing agents). 

Photodynamic therapy is a powerful medical procedure that exploits the combined action of light and a photosensitizing agent for the destruction of abnormal tissues. Ideally, the photosensitizer should accumulate in the tumor cells, and the photoactivation should be carried out by irradiation with innocuous red or near-infrared (NIR) light (photodynamic window = 650-1000 nm) in order to promote the photodynamic effects only at the injured areas. Because of their suitable photochemical and photophysical properties, porphyrins and mthe-nium-polypyridine complexes are potentially useful photosensitizers for application in photodynamic therapy (217-222). 

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