Disinfectants, be they heat or radiation or chemicals, usually kill a constant proportion of the cells present per unit time if the cells are all equally susceptible. Hence, the term ‘log kill.’ The probability of death is constant over time given a ‘single hit.’ The more cells present at the start, the greater the number killed per unit time and the longer it will take to kill them ‘all.’ One decimal reduction is one log place (exponent).               Log Nt = Log N0 – t/D.   D is the time required for a log kill.   A suspension of 105 CFU/mL of Salmonella is treated with bleach, and 90% of the cells are dead after 10 minutes. How many viable cells per mL would you expect after 30 minutes? Yes, the 30 minutes here implies 3 logs of killing. This is an excellent problem to use with the Death Equation because you can reason it through first, and then solve it using the equation.

Curren'S Math For Meds: Dosages & Sol
11th Edition
ISBN:9781305143531
Author:CURREN
Publisher:CURREN
Chapter10: Reconstitution Of Powdered Drugs
Section: Chapter Questions
Problem 40SST
icon
Related questions
Question

Disinfectants, be they heat or radiation or chemicals, usually kill a constant proportion of the cells present per unit time if the cells are all equally susceptible. Hence, the term ‘log kill.’ The probability of death is constant over time given a ‘single hit.’ The more cells present at the start, the greater the number killed per unit time and the longer it will take to kill them ‘all.’ One decimal reduction is one log place (exponent).

 

            Log Nt = Log N0 – t/D.   D is the time required for a log kill.

 

A suspension of 105 CFU/mL of Salmonella is treated with bleach, and 90% of the cells are dead after 10 minutes. How many viable cells per mL would you expect after 30 minutes? Yes, the 30 minutes here implies 3 logs of killing. This is an excellent problem to use with the Death Equation because you can reason it through first, and then solve it using the equation.

Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps with 2 images

Blurred answer
Knowledge Booster
Antimicrobial therapy
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biochemistry and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Curren'S Math For Meds: Dosages & Sol
Curren'S Math For Meds: Dosages & Sol
Nursing
ISBN:
9781305143531
Author:
CURREN
Publisher:
Cengage
Essentials Health Info Management Principles/Prac…
Essentials Health Info Management Principles/Prac…
Health & Nutrition
ISBN:
9780357191651
Author:
Bowie
Publisher:
Cengage