Bubble point of hydrophilic filter

How you can determine bubble point of hydrophilic filter by manual bubble point apparatus.

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Bubble point for hydrophilic filters has to be done by using integrity apparatus with the wetting of IPA & cool WFI.

IPA and cool wfi is used in ratio 60:40 for hydrophobic filter.

The ratio depends upon the pore size which is having the filter… in case of 0.2um filter it is 60:40 , when it is 0.22um the ratio of filter is 70:30 of IPA & cool WFI .
And it is applicable for vent filters only. In case of product filters we are using cool WFI for wetting purpose.


Which type of filter is used for filtration of oily product?

Hydrophobic filters are best suited for gas filtration, low surface tension solvents(oily product), and venting.

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any specifics resion 0.2micron 60:40 and o.22 micron 70:30 ipa

pls use the wetting solution for integrity test as mentioned in filter certificate.

As per filter COA

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As per certificate we use IPA

In case of manual bubble point test ,suppose minimum bubble point of any filter is 40 psi,slightly increase the air pressure till you observe continuous stream line of small air bubbles in solution.at the point when you observe this ,it will be bubble point of that filter.if u observe bubbles before 40 psi pressure then filter is fail in integrity test.

Hi Sir,
Based on the pore size of filter, it has the range of bubble point value I.e min and max. Based on this the pressure required to get bubbles.But some manual process also we have the standard values.

Mainly 0.22 micron filter is used for filtration of parenteral product and it’s minimum bubble point is mentioned on filter certificate.

We can not define the bubble point of the filter, it is the manufacturer of the filter who can define the bubble point of the filter.

We can follow the defined limit of the manufacturer at site.

We can not define the minimum bubble point but we can measure the bubble point of individual filter. Minimum bubble point of filter is defined by validation process done by manufacturer.