What is the best protocol for competent cell preparation ?

More Niloufar Mohammadkhani's questions See All

What is Area Under the Curve for detecting SARS-COV-2 neutralizing antibodies?

I have a question about AUC for calculating SARS-CoV-2 neutralizing antibody tests. AUC here is not the Area Under the ROC Curve. After six serial dilutions of human serum, an indirect ELISA was...

05 June 2024 8,191 0 View

Environmental Radiation modeling methods and instruments?

I am looking for tools that can simulate the transport, dispersion, and fate of radionuclides in various environmental matrices such as water bodies, soil, and air. Given your expertise in this...

21 May 2024 5,170 0 View

What is the suitable insert/vector ratio for ligation reaction?

Hi dear researchers I need to calculate the insert mass for the ligation reaction, the vector length is 7800bp and the insert length is 83bp, would you please guide me what is the correct and...

21 November 2023 6,662 1 View

Hello, how can I calculate the total amonia nitrogen (NH3+NH4) from NH4-N? that's because I used kit test for NH4-N but I need to know TAN?

Finally, I want to calculate free ammonium and for this purpose I need to know TAN.

29 October 2023 3,350 3 View

Do you know why some citations are not index in the google scholar profile, but the same citation index in the other data bases such as scopus?

Dear researcher, do you know why some citations are not index in the google scholar profile, but the same citation index in the other data bases such as scopus profile? What is the problem? If you...

25 June 2023 5,287 2 View

How to do Electrospinning zinc acetate/ PVA in 5 hours?

I do electrospinning the flowing solution to reach ZnO after calcination: I add 0.75 g Zinc acetate in 5 ml distilled water then I do ultrasonic for 5-10 min then I add 0.75 g PVA ( 89000-98000...

02 March 2023 3,016 3 View

Can anyone help me with magneto optical simulation with COMSOL?

I am trying to simulate the magneto-optic Kerr effect for a nanoparticle, using the relative permittivity tensor, which the magnetic effect comes to off-diagonal terms of the tensor, it means that...

01 December 2022 8,535 0 View

How to deposit ZnO nanofibers?

As we know. Metal oxides membrane are so fragile. How can we deposit ZnO nanofibers, after their calcination, on the Ag interdigitated electrode?

24 November 2022 10,083 6 View

CAR T-cell lenght ?

Hello everyone I am working on designing CAR-T cells. I have a question. My CAR-T cell sequence is about 1 kb. Is this length good? Do I need special features?

15 October 2022 5,710 0 View

Do you know rapid cold test method in vegetable oil ?

I need a rapid test for coldest in vegetable oil . Or How to predict the appearance of turbidity in vegetable oil?

09 June 2022 9,466 3 View

Why Do TDS and EC Increase with Larger Wastewater Volumes, While BOD and COD Decrease?

I have carried out MFC experiments on three different volumes, 50, 500 and 1000 mL of wastewater. Results after MFC treatment shows that TDS and EC are more in larger volumes of water i.e. TDS and...

09 August 2024 9,621 0 View

Could it be a cell culture contamination?

Hello everyone! I observed in my culture (htert-RPE1 cells) an orange- red particle at the bottom of the dish. It is visible to the naked eye as a very very small red dot. Could it be a...

09 August 2024 2,824 3 View

Is there any way to quantify bacterial and fungal cells in their mixed culture?

I am working in fungal fermentation of soybean meal and there is bacterial growth in them at times. I am trying to quantify fungal cell counts and bacterial cells; but I haven't been able to do at...

07 August 2024 7,535 4 View

How to normalize and take the significance of the MTT OD values with 3 replicates for the same cell-line?

Hi, I have a question about normalizing the MTT OD values for doing the statistical analysis. So, if we have 3 different plates and we call them 3 different replicates, so, first we would...

07 August 2024 8,105 4 View

Why activated CAR-Jurkat cell could not kill targets?

Previously when I co-coluture anti-CD19(FMC63) CAR-Jurkat with Raji with E:T=5:1, Jurkat can eliminate Raji in 24h. However, when I test another CAR construct, although I can dectect totally CD69...

06 August 2024 640 2 View

How to isolate lymphocytes from mouse spleen?

I have tried several times to isolate lymphocytes from mouse spleen, but all attempts have been unsuccessful. I tried most available protocols. I used different dissociation media (HBSS with Ca...

04 August 2024 9,913 7 View

How to Add Missing Water Molecules in Protein-Membrane Simulations?

I have protein-membrane simulations (PDB, PSF, DCD) and have noticed that water molecules near the protein are not visible in the simulations. How can I fix this issue? Is there a way to place the...

04 August 2024 1,200 2 View

Does long-term culture of murine Monocytes result in macrophage differentiation?

Hi, I am isolating monocytes from the bone marrow using the Mouse Monocyte EasySep kit. I want to treat these cells and monitor expression of specific markers over the course of 10 days. I will...

04 August 2024 7,282 2 View

To perform transfection with DharmaFECT Duo in AGS cells. Could you tell me what the ideal concentration is to avoid significant cytotoxicity?

I would like to perform transfection with the reagent DharmaFECT Duo (Horizon) on the AGS cell line. Could you please inform me of the optimal concentration to use without causing cytotoxicity in...

03 August 2024 3,851 1 View

Can i quantify a nanoparticle encapsulated in cell culture medium by hplc?

Hello, if you made a transwell assay where you incubate the cells with a nanoparticle-encapsulated drug and considering that in the oposite compartment you'll have both the free and encapsulte...

03 August 2024 2,730 1 View

Ajay Deepak Verma

Hi,

You can follow Inoue method (https://bio-protocol.org/bio101/e143)for preparation of ultracompetent cells and it gives very high transformation effeciency.

Goodluck!!

Niloufar Mohammadkhani

@ajaydeepak

Thanks a bunch dear ajay

Abir Chakraborty

We follow this attached protocol. It works perfectly well even for co-transformation.

Ufuk Degirmenci

Rubidium Cl protocol seems to work much better than CaCl2. https://openwetware.org/wiki/RbCl_competent_cell