Could any one help me to do oxygen radical absorbance capacity (ORAC) assay for my sample?

More Mahmoud Hefny Gad's questions See All

What is the indication of the absence of peaks in Methanol electrooxidation CV curves ?

I have several question regarding the MOR; hope anyone help me better understand. 1- in CV using (KOH+MEOH) what is the indication of absence of the redox peaks? shouldn't they exist as a sign...

28 February 2021 4,851 8 View

Is There are any idea to achieve H NMR signals for swollen compound ??

the samples are not completely soluble - just swelled the solvents that's mean the sample may be partially soluble any suggestion, please

16 February 2021 8,801 3 View

What is the best way to do symmetry in ANSYS Fluent for flow between two concentric cylinders ?

I am working on Taylor Couette flow between concentric cylinders and the results are correct for the full case. however, I wanted to do symmetry case to improve the mesh. I have tried periodic...

11 February 2021 2,193 6 View

What is the success rate of the e-learning plan in achieving the objectives of the curricula?

I need to know the reliability of the evaluation results and the rate of achievement of the course objectives, Thank you (*-*).

02 February 2021 7,828 7 View

What is the success rate of the e-learning program in your country during the time of Covid-19?

I need to know the extent of the success of the e-learning plan in countries of different capabilities, Thank you (*-*)

02 February 2021 4,712 15 View

How can I get good bands by silver nitrate staining on SSCP method?

Hi Dear colleagues This was my first experience on SSCP, and I couldn`t get any band by silver staining! Staining with Et Br was successful. I mixed the PCR product with formamide loading dye,...

01 February 2021 8,788 6 View

Why Selenium nanoparticles synthesized by PEG 200 could not be scaled up ?

I could not synthesize Selenium nanoparticles by PEG 200 at up-scale ( more than 100 ml) as it got aggregated while at small amounts it works fine , I work with 850 PPM using selenium powder in...

08 January 2021 10,049 1 View

Solving a third order polynomial matrix equation?

I want to solve the following matrix equation with respect to the matrix variable X which is a real symmetric positive definite matrix. The given matrix A is real and symmetric, "a" is a scalar,...

04 January 2021 2,945 7 View

What is the best method to add nanoparticles in organic solar cell simulation using silvaco software ??

i built the structure of the organic solar cell (ito-P3HT_PCPM-PEDOT_PSS-al) then i used BEAM statement to add sunlight so what is the best method to add nanoparticles in layers

03 January 2021 7,107 11 View

How to Calculate Local and Average NUSSELT NUMBER IN FLUENT ANSYS ?

I am simulating a single flow in a 2D tube with a uniform heat flux applying on the outer surface. I found difficulties finding the Nusselt Number or in other words a correct way to obtain...

26 December 2020 4,054 7 View

Resistor definition in Piezoelectric bimorph with ANSYS workbench

Hello, good day! I am trying to simulate similar bimorph piezoelectric harvester with below commands. However, the output power doesn't change with resistor value. Please help to find the reason. ET,10,CIRCU94,0 !SET UP RESISTOR R,1,100000 !RESISTANCE VALUE TYPE,10 !SET ELEMENT TYPE E,1,2 !CREATE RESISTOR BETWEEN NODES 1 AND 2 Thanks in advance Regards,

02 March 2021 0 0 View

How to quantitative analize the data of TNBS assay for gelatin?

Estemeed colleagues, I found some issues regarding the quantification of the data for TNBS assay. There are different protocols on how to perform that but it is clear to me the "fil rouge" that...

02 March 2021 2,616 1 View

Is There Any Feasible Method To Test Fluorescent Compounds Other Than Fluorescence Spectrometers ??

Is There Any Feasible Method To Test The Efficiency Of Fluorescent Compounds Other Than UV Spectrometers ? Suggestions Would Be Appreciated !

02 March 2021 5,785 3 View

Where can I find life cycle inventory or assessment of non woven materials?

Dear network, I am looking for the LCA or LCI or at least the energy balances of the non woven fabrics process for my master project, in specific for natural fibers, yet I have found...

02 March 2021 9,662 1 View

How to simultaneously perform multiple biochemical assays?

I am a research scholar working on heavy metal stress on plants. I will be doing biochemical characterisation( protein, carbohydrate, proline, antioxidant enzymes and many more assays) at interval...

01 March 2021 6,999 3 View

How to accurately quantify chitin?

Hi all, I have been working on the quantification of chitin in insect samples and feed for a while but I can notice that the quantification methods (e.g. exposure to HCl, NaOH, and weighing sample...

01 March 2021 1,843 2 View

Can someone suggest a way to prepare slides to observe under confocal microscope for observing fluorescent tagged proteins??

I am growing the cells on coverslips and transfecting the fluorescent tagged protein directly on them. Then i want to observe these cells under confocal microscope. Currently i am just using...

01 March 2021 6,142 3 View

Is CD44 degraded in lysosome together with hyaluronan after CD44 mediated endocytosis of hyaluronic acid?

Also when RHAMM binds hyaluronic acid, they get internalized, will RHAMM also be degraded? Or both CD44 and RHAMM will be transferred back to the cell membrane? Asking for breast cancer cell line...

01 March 2021 8,169 2 View

RIA. How to measure?

When you use RIA, with a control the unknown sample with antibodies, you bare in mind the binding sites of the antibodies. However you still need to measure labelled antigen (radioactive) and not...

28 February 2021 2,133 3 View

Why does intensity drops as concentration increases?

Is there any reason for decrease in fluorescence emission intensity of HSA,BSA when increase the concentration ?

28 February 2021 3,653 4 View

Aminah Abdullah

You need to try with a few dilution.s If it is a strong antioxidant you have to dilute to get to a correct concentration

Mahmoud Hefny Gad

Thanks Dr. Aminah, i tried with 1 mg/ml from my samples with dilution (1:40, 1:80, 1:160, 1:320) and the ORAC values for stock solution of different samples were (28.516, 28.008, 28.143, 43.535, 21.912 and 37.700). So should I increase my concentration or not??. I was wondering to ask about the correct concentration of stock solution to start this assay.not the dilutions. I want to know more details about this assay to determine antioxidant activity for my samples. Thanks for your interest and hoping to hear back from you soon.