Mohammad Nazrul Islam Bhuiyan

15 Questions 44 Answers 0 Followers

Questions related from Mohammad Nazrul Islam Bhuiyan

What is the relationship between bacterial population size and growth speed?

When we cultured in bacteria by adding growth promoting factors for rapid growth, what happened in this time. At that time bacteria growth/size are increase or both. Please any one can explain in...

02 March 2015 1,436 8 View

What is the best way to remove dissolved oxygen from a reaction solution?

My experiment requires totally oxygen free environment, how can this get? I used a reacted mixture solution in physilogical conditions.

20 September 2014 9,677 17 View

What is an alternative way to elute natural compounds without an ODS HPLC column?

I am trying to isolate active compounds from bacteria. I have used an ODS HPLC column but the active compound did not elute within this column. Can anybody give me any suggestions? My compound is...

19 March 2014 571 4 View

How can you separate a co-eluting more polar compound by HPLC?

I'm having a problem separating a single compound using 100% water as a mobile phase in HPLC (ODS). My compound is more polar and it is eluted within 3 minutes when I used 100% water as a mobile...

07 March 2014 9,915 17 View

Can anyone share the protocol of cosmosil 75 C18-OPN open column?

I need a protocol of cosmosil 75 C18-OPN open column (Nacalai USA, Inc,) or published articles.

07 March 2014 2,951 0 View

How I can isolate my compound close to the solvent's retention time (the solvents peak and compound peak are very close) through HPLC?

I am trying to isolate an active compound from an HP20 water flow fraction by HPLC. This compound is not bound in HP20 resin or an SPE (solid phase extraction cartridge). When I inject this sample...

05 March 2014 3,928 3 View

What is your opinion on the further use of recovered/recycled organic solvents for extraction of natural products?

Sometimes we use a huge amount of solvents for extracting our targeted molecules. Some solvents are so expensive and for this we recycle this solvent for further use to save our money. But one...

24 July 2013 3,695 9 View

Why is there an active compound everywhere in HPLC?

I am trying to separate my active compound through HPLC. When I injected my samples, I get more than 20 peaks and I was collected all peaks into 10 different fractions. After doing bioassay, I...

20 July 2013 7,162 1 View

Why don't active compound separate in pre-parative HPLC?

I am trying to separate my active compound through HPLC. When I injected my samples, I get more than 20 peaks and I was collected all peaks into 10 different fractions. After doing bioassay, I...

19 July 2013 8,530 6 View

How many injections in should modern HPLC Column withstand?

There are a number of factors that control the number of injections any modern HPLC column can withstand. Some of the factors are based upon the mode: reversed phase, ion exchange, size exclusion,...

17 July 2013 3,784 6 View

Why an active compound give different peaks in HPLC?

I am trying to isolate a growth factor from bacteria but when I used HPLC to isolate this compound, it gave three peak in different retention time. Why? Please give me some suggestions. Thank

09 July 2013 5,657 9 View

What are the minimum amounts of samples needed for 1H-NMR and 13C-NMR?

I only have a 0.5 mg pure sample. This amount I got from more than 66 litres of culture broth. I am worried, is it sufficient for an NMR analysis? My sample is isolated from bacteria and it is a...

09 July 2013 9,160 22 View

How can I calculate retention index (Kovalts index) by GC-MS for essential oils analysis?

I need the total procedure to identified aromatic compounds with the help of Retention Index.

04 July 2013 1,783 21 View

What solvents should be used for preparation of HPLC samples?

I used MeOH and water for extracting natural products from bacteria but active fraction did not misible in water methanol solvents for HPLC analysis. How can I prepare HPLC sample for for...

03 July 2013 3,848 7 View

What solvents should be used for preparation of HPLC samples?

I used MeOH and water for extracting natural products from bacteria but active fraction did not misible in water methanol solvents for HPLC analysis. How can I prepare HPLC sample for for...

03 July 2013 1,347 1 View