October 02, 2021: Pharmaceutical Interview Questions and Answers
1. Which are the various organization from where approved culture collections of different train of microorganisms can be obtained?
● American Type Culture Collection (ATCC)
● National Collection of Industrial and Marine Bacteria (NCIMB)
● Collection of Institute Pasteur (CIP)
● Imperial Mycological Institute (IMI)
● National Collection of Pathogenic Fungi (NCPF)
● National Biologicals Resources Centre (NBRC)
2. Explain the sample preparation process for Bioburden test.
● Sample handing area: Sample should be prepared on a laboratory bench, within unidirectional airflow cabinet or an isolator.
● Bacteria cultures handling area: Biosafety cabinet or Microbiological Safety Cabinet should be used.
● Sample preparation for Water-soluble products:
a. Dissolve or dilute the product with ration of 1 in 10 dilution in phosphate buffer solution pH 7.2, If necessary, adjust to a pH of 6 – 8.
b. If required, further dilutions can be done to get not more than 250 CFU/plate in case of TAMC, 50 CFU/plate in case of TYMC.
c. If needed, to dissolve the sample completely, triturate it in a sterile mortar and pestle in an aseptic environment to get a fine powder.
● Sample preparation for Non-fatty and insoluble material in water:
a. Suspend the product with 1 in 10 dilution in phosphate buffer solution pH 7.2.
b. A surfactant such as 1 g/L of polysorbate 80 can be used to assist the suspension of poorly wettable substances.
c. If require, adjust to a pH of 6–8.
d. If required, further dilutions can be done to get not more than 250 CFU/plate in case of TAMC, 50 CFU/plate in case of TYMC.
● Sample preparation for fatty products:
a Dissolve in isopropyl myristate sterilized by filtration, or mix the product to be examined with the minimum necessary quantity of sterile polysorbate 80.
b. Heat if required for NMT 40 °C or, in exceptional cases, to not more than 45 °C and maintain the temperature in a water bath.
c. Add pre-warmed diluent to make a 1 in 10 dilution of the product.
d. Form of an emulsion.
c. If needed, further serial tenfold dilution can be prepared using the diluent containing a suitable concentration of sterile polysorbate 80 or another non-inhibitory sterile surfactant.