Parastou Rahimizadeh

20 Questions 49 Answers 0 Followers

Questions related from Parastou Rahimizadeh

Would it be possible to determine how many Cys I have based on Ellman's assay?

I want to predict the DAR ratio based on the number of cys available for conjugation to Cys residue. I use Ellman's assay to predict the concentration of Cys after TCEP reduction. I gain a...

03 July 2024 1,068 6 View

Should Ellman reagent prepare freshly for every measurment? Would it be possible do Ellman assay by 96well plate ELISA reader or nanodrop?

I want to measure the amount of free Cys after reduction by DTT by Ellman assay. is there any possibility of measuring absorbance (412 nm) by nanodrop one instrument? 96 well plate ELISA reader...

22 May 2024 4,432 1 View

How shall i consider extinction coefficient unit?

I want to determine the conjugated drug to IgG ratio by nanodrop. I know the extinction coefficient of IgG and drug by M-1cm-1 but all the unit in the nandrop program is based on g/ml and so on...

16 May 2024 9,173 4 View

Why sequencing result doesn't show any homology with my expected gene sequence?

I had a BL21 (DE3) cell which I always use to express GFP protein which fused to a coil. Based on the vector map given to me, this gene is inside the pQE80 vector which has resistance to...

15 December 2020 4,749 4 View

Why the expressed protein band Molecular Weight (MW) is lower than expectation?

I tried to express my protein in BL21(DE3) bacteria. The desired protein MW is 65.5 KDa and I know my protein will be in an insoluble form (inclusion body). I separate soluble and insoluble...

21 October 2020 4,374 8 View

How can i interpret ITC result?

I want to investigate the interaction between two proteins by ITC. I choose two proteins that I'm sure don't interact with each other as a control. but ITC results show there is some interaction...

23 June 2020 2,451 5 View

Is there any correlation between spirtuality and immune system?

I want to know how spirtuality control the biological pathway involved in immune function. would it be possible to refrence some articles about this subject?

06 October 2017 3,762 6 View

Which residue of enzyme molecule attach to support during immobilization?

during immobilization of enzyme on support, for example activated chitosan with glutaraldehyde, which surface residue of enzyme molecule intracte with support?

08 August 2015 7,343 9 View

How can one reduce As+3 to As0 without interference of As+5?

When we have two forms of As in an environment, how and in which potential does the reduction of As+3 to As0 occur, and the interference of As+5 form is zero?

16 February 2015 887 3 View

What is the difference between desiccation and freeze dryer for sample preparation?

I want to prepare my sample for TGA analysis, I want to know is there problem for using desiccator instead of freeze dryer for drying samples? My sample is enzyme in free form and immobilized...

10 January 2015 7,369 4 View

How does tritonx100 effect enzymatic activity?

I want to show the effect of some detergent on enzymatic activity in immobilized form and free form. The data shows that I get different results. Tritton has bad effect on immobilized form(as...

09 January 2015 7,072 14 View

Can anyone help me with FTIR interpretation?

I immobilize enzyme on chitosan macrobead with Glutaraldehyde as crosslinker. I want to know how FTIR confirm immobilization? Which wavelength is related to chitosan with glutaraldeyde and which...

06 January 2015 4,312 9 View

which particle size is betterr for enzyme immobilization?

I want to immobilize enzyme on chitosan macrobead, i want to know macro size of particle doesn't have any advantages for immobilization? I use CMC as substrate,can I relate this viscose substrate...

05 January 2015 2,672 8 View

Which site is better for adding an His-tag to aprotein?

I want to clone a gene in a vector with His-tag. My protein is an enzyme and its active site is in the center. Is there any difference between adding an His-tag at the C-er or N-ter of the protein?

05 January 2015 9,520 4 View

Why optimum pH shift from 6.5 to 8 after immobilization?

I immobilize enzyme on chitosan macrobead after activating them with glutaraldehyde. I want to set up optimum condition for emobilized enzyme. Optimum pH shift from6.5 to 8?! Is there any reason...

02 January 2015 768 6 View

Why I can't immobilize enzyme on chitosan macrobead?

I want to immobilize my produced enzyme on chitosan macrobead with glutaraldehyde as crosslinker.i treat 1 gram of chitosan macrobead by10ml glutaraldehyde 0.3% based on literature,after that...

28 July 2014 2,319 12 View

Which procedure for gene cleaning is more effective?

I did a digestion for gene and now I want to clean it for ligation.Gene length is about 1600bp. Which one is better: gel extraction kit or ethanol precipitation? Which size segment sediment in...

21 February 2014 8,745 7 View

What is my problem in cloning?

I want to clone my gene to expreesion vector in Ecoli, after I clean my pcr product, I have a good band. In digestion step, after digesting the gene I don't get any band, but I perform a ligation...

01 February 2014 9,928 16 View

Gel mobility shift on SDS-PAGE

I tried to express a protein in the bacteria system (BL21 (DE3)). This expressed protein in any temperature and condition shows a bond lower than expectation on SDS-PAGE (theoretical MW:66284 Da)....

01 January 1970 4,808 3 View

Would it be possible do Ellman assay by 96well plate ELISA reader or measure by nanodrop?

I am gonna do an Ellman assay and based on the datasheet I should measure the molar absorption at 412 nm. I wonder ELISA reader or nanodrop one can be used to do measurements at this wavelength...

01 January 1970 1,941 4 View