CONTROL OF MOD BY CHEMICAL AGENTS CONTD..

E) ALDEHYDES:   
                             They have general formula (R-CHO) . The commonly used aldehydes are formaldehyde & glutaraldehyde.They inactivate proteins by forming covalent bond  cross-links with several organic functional groups on proteins(-NH2, -OH, -COOH, -SH).
  • Formaldehyde(HCHO):   It is gas at high temperature & solid at room temperature.  It is also marked as aqueous Formalin, used which contains 37-40% of formaldehyde. Formalin was extensively used to preserve biological specimens & inactivate bacteria & viruses in vaccines. 
Uses: Formaldehyde in solution is used to sterilize certain instruments. However,they may leave a residue & instruments should be rinsed  before use. Formaldehyde in gaseous form is used to disinfect & sterilize the enclosed area.

MODE OF ACTION:   It is alkylating agent. They insert alkyl group into nucleic acid & proteins forming a bridge. These changes the structures of molecules leading to cell death. For more visit this link; http://www.icm.tn.gov.in/drug%20formulary/DISINFECTANTS%20&%20ANTISEPTICS(13).htm 

  • Glutaraldehyde:  It is a saturated di-aldehyde. It is alkylating agent usually employed as 2% solution(Cidex). When it is used as 2% solution , it is bactericidal, tuberculocidal, & virucidal  in 10 minutes & sporicidal in 3 to 10 hours. Since the efficacy of glutaraldehyde is not greatly affected by organic matter, it is used on surgical instruments where blood may be present. It is used to sterilize optical instruments like fiber optic endoscope . Please visit this links; 
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2672.1980.tb01217.x/pdf
http://en.wikipedia.org/wiki/Glutaraldehyde  
msdssearch.dow.com/.../dh_049c/0901b8038049cb2b.pdf?.
www.ncbi.nlm.nih.gov › ... › Br Med J › v.280(6211)
                                   




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