To determine the isoelectric point of a protein, first establish that a gel:
(a) Contains a denaturing detergent that can distribute uniform negative charges over the protein’s surface.
(b) Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
(c) Is washed with an antibody specific to the protein of interest.
(d) Neutralizes all ionic groups on a protein by titrating them with strong bases.
The correct answer is:
(b) Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Explanation:
To determine the isoelectric point (pI) of a protein, isoelectric focusing (IEF) is used. IEF relies on a stable pH gradient created by ampholytes (small charged molecules) in an electric field.
- Proteins migrate within the gradient until they reach their isoelectric point (pI), where their net charge becomes zero and movement stops.
- (a) Incorrect: SDS is used in SDS-PAGE, not IEF. It denatures proteins and applies a uniform negative charge, making pI determination impossible.
- (c) Incorrect: Washing with antibodies is a step in Western blotting, not isoelectric focusing.
- (d) Incorrect: Titrating ionic groups with strong bases does not determine pI; instead, proteins naturally stop moving at their pI in a stable pH gradient.



46 Comments
Arushi
March 3, 2025👍👍
Monika jangid
August 14, 2025Amphotlyte separate protein on the basis of iso electric point or charge
Prami Masih
March 4, 2025Done ✅ sir
Anjani sharma
August 14, 2025Answer b is correct as in isoelectric focusing point the proteins migrate with ph gradient until net charge is zero
Karishma Don
August 14, 2025It is achieved using ampholytes, which establish a stable pH gradient when an electric field is applied.
Mitali
August 14, 2025(b) Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Soniya Shekhawat
August 14, 2025Ist occuring IEF in which protein are separate on the basis of PH with the net charge of protein is be have zero so B is correct option .
Khushi Mehra
August 14, 2025Iso electric point refers to the migration of protein within the gradient until the net charge on protein becomes zero . This can be done by adding ampholytes which can act as an acid as well as base.
Soniya Shekhawat
August 14, 2025IEF in which protein are separate on the based of PH (ampholytes )with the net charge of protein is be have zero so B is correct option .
Khushi Mehra
August 14, 2025Iso electric point refers to the migration of protein within the gradient until the net charge on protein becomes zero . This can be done by adding ampholytes which can act as an acid as well as base.
Correct option is b
Urmi sisodiya
August 14, 2025Option b is correct bcoz net charge of proteins have to be zero
Deepika sheoran
August 14, 2025Option b is correct
Because isoelectric focusing proteins move through a ph gradient until they reach a point where their net charge is zero.
Roopal Sharma
August 14, 2025B is correct as protein is separated on the basis of oh gradient
Surbhi Rajawat
August 14, 2025To determine isoelectric point we must have a Ph gradient which will help in neutralizing the protein therefore B is correct option
Ruchika
August 14, 2025Option b is correct 👍
Ruchika
August 14, 2025b is correct 👍
Shivani
August 14, 2025Option b is correct .
Priya khandal
August 14, 2025Exhibits a stable pH gradient when ampnolytesbecome distrbuted in a electric field
Ankita Pareek
August 15, 2025To determine isoelectric point isoelectric focusing is used where proteins separate on the basis of their.. charge on proteins depends on ph ief is relies on stable ph gradient so option b is correct
Kajal
August 15, 2025Exhibit a stable ph gradient when ampholyte gets distributed acc. To the PH gradient
Kavita choudhary
August 15, 2025Answer is b
Divya rani
August 16, 2025B is right answer because IEF is on stable pH gradient and in electric field so charge is important
Neeraj Sharma
August 17, 2025Option b as we need a stable ph gradient to find the isoelectric point
Seema
August 18, 2025👍
Shrddha
August 23, 2025Amphobialite is a word that can donate and accept iones pi is the ph at which molecule has no net electric charge
Bharti Yadav
August 24, 2025Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
MOHIT AKHAND
August 24, 2025Done sir ✅
Priyanka Choudhary
August 24, 2025B is correct answer,Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Anil Choudhary
August 24, 2025Option b is correct because net charge of proteins have to be 0
Bhavana kankhedia
August 24, 2025Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Alec
August 24, 2025ans is b – establish a stable ph gradient when ampholytes are distributed in the electric field.
Anju
August 24, 2025Ans:B
In Isoelectric focusing protein moves with ph gradient till the net charge is zero
Anjali
August 24, 2025Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Shivani Panwar
August 24, 2025Answer B…👍
Devika
August 24, 2025B is correct
Kashish yadav
August 25, 2025👍👍
Ayush Dubey
August 25, 2025Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
sakshi khatri
August 25, 2025done
Shriyanshi verma
August 30, 2025Option b is correct bcoz net charge of proteins have to be zero
Swati Choudhary
August 31, 2025(b) Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Shobha Kanwar
August 31, 2025Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Anisha jakhar
September 3, 2025Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Muskan Yadav
September 3, 2025Exhibits a stable pH gradient when ampholytes become distributed in an electric field.
Somya Yadav
September 5, 2025Option b is correct
Because isoelectric focusing proteins move through a ph gradient until they reach a point where their net charge is zero.
Aakansha sharma Sharma
October 1, 2025Option b is correct
Because isoelectric focusing proteins move through a ph gradient until they reach a point where their net charge is zero.
Harish Kumar
November 18, 2025B Option is correct