Ultraviolet light inactivated

Heat is the most reliable method of virus disinfection. Most human pathogenic viruses are inactivated following exposure at 60°C for 30 minutes. The virus of serum hepatitis can, however, survive this temperature for up to 4 hours. Viruses are stable at low temperatures and are routinely stored at -40 to -70°C. Some viruses are rapidly inactivated by drying, others survive well in a desiccated state. Ultraviolet light inactivates viruses by damaging their nucleic acid and has been used to prepare viral vaccines. These facts must be taken into account in the storage and preparation of viral vaccines (Chapter 15). 

S. S. Qian, M. Donnelly, D. C. Schmelling, M. Messner, K. G. Linden, and C. Cotton, Ultraviolet light inactivation of protozoa in drinking water. Water Research 38, 317-326 (2004). 

T.P. Coohill, R.A. Deering (1969). Ultraviolet light inactivation and photoreactivation of Bastocladiella emersonii. Radiation Res., 39, 374-385. 

Yellow prisms from propylene oxide or petr ether. Solvated crystals from more polar solvents, such as methanol or ethyl formate, mp 62-64°. Distills at 120-125" at 5 x lO-3 mm pressure, nj 1.6410 (calculated from refractive indexes of 20-70% solas in mineral oil), uv max 324-325 nm (E 1835) Baxter, Robeson, J. Am. Chem. Soc. 64, 2407 (1942+ Practically insol in water or glycerol sol in abs alcohol, methanol, chloroform, ether, fats and oils. Ultraviolet light inactivates vitamin A and its solns which exhibit a characteristic green fluorescence. The free alcohol is sensitive to air-oxidation, but oil solns of it are quite stable. Esters of vitamin A are more stable to oxidation. LDn (10 day) in mice (mg/kg) 1510 i.p. 2570 orally (Kamm). 

The ultraviolet light inactivation method for the measurement of retinol, pioneered by Bessey et al. (1946), is based both on the high absorbancy of retinol and its esters at 325 nm and on their susceptibility to photooxidize and polymerize to nonabsorbing products. In the original procedure (Bessey et al, 1946), aliquots of plasma or serum were saponified to remove reacting contaminants and extracted with a solvent of low volatility then the absorbancy at 328 nm was measured before and after exposure to ultraviolet light. Because microcuvettes can be used, the procedure can be scaled down satisfactorily to the use of very small amounts (0.6 ml) of serum. The sensitivity is about 3 ng retinol. The procedure has been used extensively in nutrition surveys and particularly in studies in Guatemala and Brazil (Arroyave et aL, 1979 Araujo and Flores, 1978). 

Figure 9.4 Repair of DNA inactivated by ultraviolet light. Light causes die dimerization of adjacent thymine residues that block DNA replication. The four enzymes shown are involved in removal and replacement of a portion of the DNA that contains the dimer.

Hadjok, C., Mittal, G. S., and Warriner, K. (2008). Inactivation of human pathogens and spoilage bacteria on the surface and internalized within fresh produce by using a combination of ultraviolet light and hydrogen peroxide. J. Appl. Microbiol. 104,1014-1024. 

The presence of proflavine protects some viruses against inactivation by ultraviolet radiation and proflavine has been shown to inhibit formation of thymine dimers in DNA.86 (6) The sensitivity of microorganisms to ultraviolet light increases with, but is not proportional to the square of, the thymine content of the DNA.86 (7) Substitution of... 

The correlation between definite photoproducts and biological action of ultraviolet light discussed in this section is confined to a particular action of ultraviolet light, namely an inactivating or lethal action. Microorganisms are killed, DNA synthesis in cells is inhibited, transforming DNA is inactivated, template activity of DNA is reduced, and phage and viruses are inactivated because the pyrimidine dimer which is formed in-strand is apparently able to provide a block which hinders DNA or RNA replication. 

Bolton JR, Dussert B, Bukhari Z, Hargy T, Clancy JL (1998) Inactivation of Cryptosporidium parvum by Medium-Pressure Ultraviolet Light in Finished Drinking Water, Proc. AWWA 1998 Annual Conference, Dallas TX, Vol. A 389-403. 

Clancy JL et al. (1998) Inactivation of Cryptosporidium Oocysts in Water using Ultraviolet Light, J. Am. Water Works Assoc. 90 92-102 cited in Clancy (1999). 

Clancy JL, Bukhari Z, HargyTM, Bolton JR, Dussert B, Marshall MM (2000) Comparison of Medium- and Low-Pressure Ultraviolet Light for Inactivation of Cryptosporidium parvum Oocysts, J. Am. Water Works Assoc. 92, No. 9 97-104. 

A monolithic monofunctional enzymatically coupled FET sensitive to urea was first fabricated by Kuriyama and Kimura s group (44). Their integrated FET chip has two hydrogen ion-sensitive FET elements. One FET element has a urease-immobilized membrane, working as an enzyme FET, and the other has a ultraviolet (UV) light-inactivated, urease-immobilized membrane (see Section 3), working as a reference FET. 

Practically insoluble in water, ethanol, chloroform, and ether. Soluble in dilute solutions of alkali hydroxides and carbonates, yielding a clear orange-brown solution soluble in hydrochloric acid and in sulphuric acid, yielding very pale yellow solutions. Solutions are inactivated by ultraviolet light alkaline solutions are sensitive to oxidation and acid solutions are sensitive to heat. 

Kaplan EH, Campbell ED, McLaren AD. Photochemistry of proteins. VIII. Inactivation of insulin by ultraviolet light. Biochem Biophys 1950 4 493-500. 

A. H. Havelaar, C. C. E. Meulemans, W. M. Pot-Hogeboom, and J. Koster, Inactivation of bacteriophage MS2 in wastewater efQuent with monochromatic and polychromatic ultraviolet light. Water Research 24(11), 1387-1393 (1990). 

Surface moisture may influence the susceptibility of baculovirus deposits to inactivation by ultraviolet light. Consistent with the studies on VACV, it was observed that PbGV inactivated more rapidly in wet vims films exposed to UV radiation than in dry films [19], as in the cases of TnNPV [58] and HzSNPV [55], These findings suggest that surface moisture favors the inactivation of baculovimses exposed to UV radiation. 

Ignoffo, C.M., Hostetter, D.L., Sikorowski, P.P., Sutter, G., and Brooks, W.M., 1977. Inactivation of representative species of entomopathogenic viruses, a bacterium, fungus, and protozoan by an ultraviolet light source. Eviron. Entomol., 6 411—415. 

Prions are very difficult to inactivate. Agents that completely denature protein, such as bleach and strong alkali or acid (see the Dementias section later in the chapter) are effective, but ultraviolet light, routine formalin fixative, and standard disinfectants fail to eradicate prions. 

CHEMICAL PROPERTIES stable under ordinary conditions of use and storage hazardous polymerization has not been reported non-volatile hydrolyzed by bases reacts with strong oxidizers inactivated by inert clays and by anionic surfactants unformulated products are corrosive to common metals decomposes under influence of ultraviolet light FP (NA) LFL/UFL (NA) AT (NA) HC (NA)... 

The trichothecene mycotoxins are nonvolatile compounds produced by molds. They are very stable and resist heat- and ultraviolet light-induced inactivation. Only after heating at 500°F for 30 minutes will the toxins inactivate. 

JD Druce, D Jardine, SA Locarnini, CJ Birch. Susceptibility of HIV to inactivation by disinfectants and ultraviolet Light. J Hosp Infect 30(3) 167-180, 1995. 

Bishop JM, Quintrell N, Koch G Poliovirus double-stranded RNA — Inactivation by ultraviolet light. J Mol Biol 1967, 24(1) 125—128. 

The trichothecene mycotoxins are low-molecular-weight nonvolatile compounds produced by certain molds. They are not water soluble but are soluble in alcohols. They are very stable to heat and ultraviolet light but are inactivated by alkaline... 

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