- Frank Roscher added an answer:4Does anyone know of an aerosol device able to spray small quantities of liquid nano-microlitres?We would like to apply small quantities of liquid as an aerosol to specific objects.
Dear Christopher, Aerosol-Jet deposition might be an option where you have the possibility to deposit Aerosol generated out of a "ink" container.Following
- Titus Sobisch added an answer:8How do I solubilize samples in aqueous solutions?
I am not from pharmacology background. But I would like to determine my sample aqueous solubility after spray-drying.
I chance upon paper below
Paper:Solid Dispersions of α-Mangostin Improve Its Aqueous Solubility Through Self-Assembly of Nanomicelle
"An excess amount from the samples (30 mg)
was added to 1 mL of phosphate-buffered saline (PBS)
at pH 7.4. The mixtures were vortexed for 5 min
and sonicated for 1 min and then centrifuged at
20,000g for 5 min. The supernatant was collected, filtered
through a 0.45-:m syringe filter, and diluted in
methanol. The samples were then analyzed using a
Since, my sample wall cannot be dissolved by PBS. I used water in replaced.
And my sample before spray-drying does not dissolve in water at all. So I just use 10mg.
But after spray-drying, its more soluble. Should I use it at 10mg as well? Or Excess like its written?
Because I want to compare before and after spray-drying solubility. Seems right to use it at 10mg. To compare properly
As long as the spray drying does not change the chemical composition solubility should be the same before and after the process, however, kinetics might be changed considerably.Following
- Philippa Ojimelukwe added an answer:6Which is best to use, Tween 20 and Tween 80?I'm wondering if its possible to use Tween 20/80 as a carrier/solubilizer to dissolve a hydrophobic substance. So far, I tried heating either Tween to around 70C, and it manage to dissolve my hydrophobic substances. But when I remove it from the heat plate, it starts to turn into like white solid like ghee, which I guess happens because of the decrease in temperature to the cloud point?
I'm trying to understand the differences in both Tween. I read somewhere that tween 20 is better to emulsify small amounts of lighter oils; whereas Tween 80 to emulsify larger amounts of heavier oil.
Then I check the HLB value (wikipedia) in which:
12 to 15: detergent
12 to 16: O/W (oil in water) emulsifier
16 to 20: solubiliser or hydrotrope
Tween 20 (16.7) seems like a better choice as it can act as a solubiliser or O/W emulsifier compare to Tween 80. But then other sources said tween 80 is better to emulsify larger amount of heavier oil?Which sounds like its better to solubilised my hydrophobic substances.
Erm. Do correct me if I'm wrong.
This information might help. Tween 20 has more hydroxy groups than Tween80. However, Tween20 works better in some experimental environments while Tween80 works better in other environments. There are no hard and fast rules since many factors affect emulsion stabilizationFollowing
- Nadiir Bheekhun added an answer:18What is a typical range of %wt solid fraction needed to obtain a concentrated ceramic slurry?
Can anyone suggest me what would be a typical range of %wt solid fraction needed to obtain a concentrated ceramic slurry for spray-drying? I have come across some works wherein 50 %wt of solid fraction have been employed.
Any justifications will be greatly appreciated.
Thanks a lot.
Dear Dr. Carlos,
Many thanks for your suggestion. I'll look into the Brongniart’s formula and the answers you provided.
- Amaraporn Wongrakpanich added an answer:3How can I prepare chitosan nanoparticle sample for SEM?
I have some chitosan nanoparticle suspension and I would like to observe the morphology through SEM. I tried to air dry 1% suspension on SEM stub with carbon tab, but cannot observe sphere particle. I have read some papers using dry powder to do SEM after spray dry. However, we do not have a spry dryer. Is there any other methods I can use to prepare SEM sample? Thanks.
For me, my first choice will be to try dring on the stub then sputter coat like this paper http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3304394/
But if normal drying doesn't work, you might need to try critical point drying or freeze drying. I think you should talk to someone in your microscopy core. I bet they could help with this technique.
- Auwal S M added an answer:2Can spray dried peptide loaded chitosan-alginate microparticles be produced?
Alginate is a water-soluble linear polysaccharide composed of alternating blocks of 1– 4 linked α -L-guluronic and β-D-mannuronic acid residues ,whereas chitosan is a co polymer of D-glucosamine and N-acetyl glucosamine.
They have favourable properties of biocompatibility, biodegradability, pH sensitiveness and muco adhesiveness.
It seems. But, the peptides can be encapsulated by cross linking chitosan with TPP.Then alginate will be used as the second coating layerFollowing
- M. Ibrahim added an answer:13How long should we ball-mill a slurry before spray-drying?
For an aqueous slurry of weight 500g (water+binder+ceramic), what is a reasonable duration for rolled ball-milling before spray-drying?
At what would be a recommended speed of rotation?
Thanks in advance.
I would like to confirm with you guys, as my doubt falls under this topic, whether I can keep my ball-milled slurries for some days, say 10 days, and then spray-dry them? The spray-drying facility is quite far and not possible to get a slurry prepared and spray-dry on the same day. I plan to prepare a batch, then carry out the spray-drying.
Of course, I would be able to mix the ball-milled slurries using a magnetic mixer prior to spray-drying.
Your suggestions will really help.
- Roberto Molteni added an answer:7Any suggestions on how to improve the powder yield of spray dried oil emulsions?
How can we reduce the loss of oil emulsion samples in a spray drying chamber?
I agree with the answers, especially with Agarwal. I suggest to grasp the optimization issues with a fractional factorial design because there are many parameters (type of encapsulation, temperatures, flow rate etc). Later, you can refine it with a more precise factorial design.Following
- Denis Poncelet added an answer:2What is deference between spray drying and spray chilling in microencapsulation of probiotic bacteria and which one is better?
Microencapsulation as one of the most important techniques has remarkable effect on probiotic survival. There are several techniques to encapsulation of probiotic bacteria such as spray drying and spray chilling.
Spray drying you start from a wet suspension of cells. They are dried in a few second and bring to 40 to 60 °c. The stress is then quite high.
Spray cooling you start from a dry suspension of cells in melt material at 60-80 °c. Also stressful.
The way you master each process will control the final viability of cells. It may depend of the process parameters, the type of cells (very important) but also how you prepare and formulate the cells.
Now in application, spray drying beads would dissolve in water and not spray cooling beadsFollowing
- Mihai Ognean added an answer:5How can we improve the viability of lactobacillus casei after spray drying?
What are the factors that needed to be considered for a better survivability?
why the reproducibility in the viability count results in the MRS agar plating technique are lesser ? How can we improve this?
Also, in freeze dried sourdough production the LAB survival rate is increased if the culture is cold-adapted for 2h at a temperature with 15 oC lower then the cultivation temperature before freezing.Following
- Arun Chattopadhyay added an answer:3Can you suggest some training center for handling fluidized bed spray drying?
We have a culture collection with probiotic bacteria and produce in liquid form. We have now acquired the equipment and we want the probiotic powder. Thanks for your help.
You are most welcome.Following
- Md Ramim Tanver Rahman added an answer:4Does anyone have the experiences of Vacuum Spray Drying (VSD) of Concentrated Fruit Juice ?
VSD with low temperature treatment 40-60C.Following
- Md ZOHURUL Islam added an answer:3Is there research has done by the Vacuum Spray drying process? Can someone give me idea about this topic?
Vacuum spray drying process.
Thank you very much Mr Dustin CooperFollowing
- Hassan Mohamed added an answer:3Would dodecane be a suitable organic solvent to spray dry with beta carotene? If not what is commercially used as the organic solvent?
Beta carotene melting point 180 degrees celsius.
Dodecane boiling point 220.
saraniya bharanthi , I know dodecane has optimum extraction of the algae biomass , but is it commercially used as a solvent for spray drying . And if so , wouldn't the temperature of the hot nitrogen cause the beta carotene to melt?Following
- Patrick Druggan added an answer:6What will be the suitable conditions for vacuum spray drying of concentrated fruit juice?
I have carried out 50:50 (juice solid: maltodextrin solid) ratio, but the product, powder not free flowing. solidification/ coagulation occur. What should be the suitable conditions? I am also doing my experiments in different proportions.
Do you know what the chain length for the maltodextrin is? This could have an effect on your process.Following
- Ashish Kumar added an answer:13Which of these processes (Freeze Drying, spray drying and evaporation by heating) is best for nano suspension drying into nanopoweder?
I had synthesized nanoparticles as nanosuspension. I want to convert the nanosuspension into nanopowder. I am thinking of one of these drying processes (spray drying and evaporation by heating). Accordingly, I am in need of advice about which process would be best in terms of the least affecting the size, properties and the dispersion of the nanoparticles. In other words the one with the least possibility of nanoparticles agglomeration into larger flocs.
Thanks in advance
Freeze Drying is the best technique. but is time and energy consuming. also only suitable for small amount.Following
- Arjun Radha Krishna added an answer:3How can I predict the Glass transition temperature of spray dried powder and Gordon taylor model?
I perform DSC, temperature -60 to 120C, of my spray dried powder sample. But i cant set the base line which transition 1 or 2 will be the glass transition temperature Tg. When i set to base line i got onset, endset and midpoint temperature. Which one is the Tg. In Gordon Taylor model, Tg, Tgs, and Tgware the glass transition temperatures of the mixture, solids, and water, respectively,xw is the mass fraction of water, and k is the Gordon-Taylor parameter, how can i predict. specially k value . my sample solid about 96% water 4%.
I agree with Piyush!Following
- Ludwig Christian Ries added an answer:8How can you achieve a zero emission level of SPM (Suspended Particulate Matter) during spray drying?
We are manufacturere of Pigment. Right now we are achieve the SPM level <30% from Spray Drying. But we want to achieve the SPM level near about zero. Can any one suggest me the right direction?
Dear Mr. Gopal,
the large amount of aerosols i would try to remove with an electro static method. This is proved since quite long in removing aerosols for example from coal firest exhaust. As i also have written in the beginning.
For the rest filtering makes it possible to receive zero emission.
It is also questionable whether it is possible to develop and use a 2 stage electro static method, which could increase efficiency and at the same time reduce load for the final filter. so the filter would keep longer.
For my opinion i think that this is the way you could search for an technical solution.
- Md ZOHURUL Islam added an answer:3How to spray dried soy sauce in higher TSS?
I am trying to develop soy sauce powder by using spray dry and using modified starch as filler.
The initial TSS (total soluble solid) of soy sauce is 32. Then I mixed soy sauce (60%) with modified starch (20%) & water(20%) until I got TSS 36. The result is well enough although the flavor isn't strong enough.
Next, I was trying to increase the TSS by removing additional water. Soy sauce (75%) was mixed directly with modified starch (25%). The final TSS before spray drying was 49. However, it resulted coarse powder.
This coarse powder also happened when I spray dried chicken extract under the same TSS, which was 49 - 50.
Usually, the spray dry is set under T inlet = 145 - 155 C and T outlet = 95 - 100 C
I don't have a good basic knowledge about spray dry, so I'm really confused about it.
The questions are:
1. How to produce nice spray dried powder in higher TSS for example 50 or higher without making it coarse?
2. Somehow when I try to spray dried slurry with TSS 50 (under the same temperature as I explained above), the upper chamber becomes wet which means the powder isn't dry enough. But the same problem doesn't exist when the TSS is around 35-40. How to avoid this wet chamber? Why does it occur?
3. How to strengthen the powder flavor besides by reducing the filler in slurry?
Thank you for any comments!
I am Agree with Mr Marali. It is very common if you increasing the TSS and feed rate final product quality will not good. Better to decrease the TSS (30-35%). To retain the flavor you should need to low temperature treatment. Then you can try Vacuum drying process. If you want to spray drying please find out the proper filling ratio, lower the feed rate, increase the atomizer pressure or speed (rpm). Thank you.Following
- Marcelo Pagnola added an answer:12What is the best way to do powder coating?
I need to use a sintering aid and it is important to have a uniform coat over grains to achieve better microstructure. What is your suggestion? Would you please introduce a good reference?
You may too turn to chemical coating method : Spontaneous PolimerizationFollowing
- S. Sadeghzadeh added an answer:2What is the usual methods for granulating the silica gel in industry?
I know that some methods such as oil-drop and spray drying may be used in industry to granulate the silica gel. I want to know which method is used really in industries?
Thank you very much Elena.
That's very good. Do you know any about the "air granulation" mentioned there?Following
- Sherlyn Tang added an answer:11Can anyone help me to check this protocol for probiotic microencapsulation?
I did the experiment a number of times buy am still not able to obtain the expected result. I would like to seek help from everyone. The protocol as follows:
1. Dissolve 1%maltodextrin and 1%CMC (carboxymethyl cellulose) separately in sterile distilled water.
2. Centrifuge probiotic culture and wash with PBS.
3. Dissolve pellet with 1% maltodextrin and follow by CMC, stir using magnetic stirrer for 5 minutes.
4. Perform acidity test for the mixture.
Result obtained: survivability of control sample is higher than malto+CMC encapsulated sample at pH1.5 for 90min.
May I know which step went wrong? Or, is it a MUST to perform spray drying process in order to obtained the encapsulated cells?
Thanks for all the suggestions. Do you think spray dry process must be perform to complete the microencapsulation? I meant, do you think the cells will be better encapsulate if perform spray drying after mix with the encapsulated agents? ThanksFollowing
- Xianqian Zhu added an answer:2How can I form a stable emulsion of fish roe that can be spray dried?
I have tried solubilizing the fish roe in dilute salt solutions. But that still forms 2 separate layers. How do I form a stable emulsion?
Try colloid mill to make the particle size smallerFollowing
- Yunier Paneque added an answer:3What is the effect of inlet air temperature on the morphology of powder particles using protein as a carrier?I am using protein as carrier in spray drying of juice powder.
An elevated temperature of air entering the drying chamber influences the hardening of the particles through which the steam / water or remaining attached diffuse air, will cause such diffusion takes place very slowly.
The inlet temperature of the air can cause powder sticking on the wall of the drying chamber. When the temperature is not enough for the water to evaporate external to the particle before it reaches the wall of the drying chamber is sticking.Following
- Ehsan Oskoueian added an answer:14What are the economic, easy and novel techniques to harvest the microbial mass from media in industry?
Freeze-drying and centrifuging are expensive techniques, spray drying has its own challenges and I guess the ultrafiltration might be challenging as well. Is there any other option?
Dear Istvan Balogh
I got the point. Thank you for the helpful information.Following
- Matthias Steiert added an answer:3I am looking for possible methods of drying drug loaded nanoparticles (polymeric nanoparticles) apart from freeze drying. Can someone suggest?
There are very few methods in literature for drying nanoparticles - mostly freeze drying is used, few others are spray drying, oven drying, evaporation etc. However, these often lead to agglomeration/change in size and also in some cases properties. I am interested in a simple and effective method of drying.
Spray drying might be another option. This link is just to get your started looking into it http://en.wikipedia.org/wiki/Nano_spray_dryerFollowing
- Carlos Alberto Fuenmayor added an answer:3Newbie here: How to determine Encapsulation Efficiency of an encapsulated hydrophobic antioxidantI am thinking of encapsulating a hydrophobic antioxidant (lets call it A) using a spray dryer.
Since it is hydrophobic, i was thinking of dissolving A with a vegetable oil, maltodextrin as a wall material and gum arabic as surfactants in water. This emulsion is then spray dried.
However, I am not too sure how to determine encapsulation efficiency. Any advice?
*sadly i do not process a spray dryer capable of handling solvent.
Sure there are other ways. You can check which is a good solvent for your compound (ethanol, methanol, usually work well for hydrophobic phenolics, but I don't know the entity of "A").
First of all you have to extract A from the encapsulating matrix. You can try to do it directly in the solvent, however maltodextrin can be tough to release its cargo when it is dispersed in a non polar solvent. One possibility to tackle this is to grind the capsules very well prior to the extraction and to do the extraction for a long period.
Consider also where would you want A to be released (if you encapsulate it, I guess you want to release at some point). In that case what you can do is to perform release experiments in the medium that your are interested, i.e., water at a certain pH (no matter if it is acqueous phase, aftwerwards it has to be released there) and then measure how much is actually released to that medium. At some point there will be equilibrium, and the maximum amount that is released can be considered for calculating and "Effective Efficiency Ratio". Meaning that even if you have more compound encapsulated inside, it won't be released, so you can consider it "lost".
If you really want to calculate how much is encapsulated, though, the most accurate thing to do is thermogravimetric analysis (TGA). You can read further about it, there is plenty of information online and probably someone in your university has one TGA instrument (Chemistry or Chemical Engineering Departments usually do).
Remember you are encapsulating an antioxidant, so instead of measuring the concentration (for example with chromatography), you can use the classical Folin, DPPH, ABTS or any other simple in-vitro antioxidant capacity test!
Now good luck with your experiments!!Following
- Nabajyoti Biswas added an answer:14How to dry a sample solution?I have a solution of protein hydrolysate and I want to dry the solution without changing the peptide activity. Freeze drying unit isn't working and I need another method of drying the sample. Can I use a spray drier? What will be the protocol.Amit Taneja
Spreay drying is of course a good option but whether in that high temperature the peptide activity remain same? I know that peptides are stable compounds only but not sure whether its activities reman stable too?Following
- Olivia Ho added an answer:13Can someone help me with my surfactants questions?So I've just started looking at surfactants, emulsions etc.
I've been looking at some journals on emulsion/dispersion for spray drying etc. and all, but without much success.
Let's say I want to create an O/W emulsion (wherein a hydrophobic substance in an aqueous phase contains maltodextrin).
What I am not sure about is:
1) Some papers just use 1 surfactant like Tween 80; whereas some use 2 or more surfactants. For O/W, must I use 2 surfactants or is just 1 kind enough? I see HLB values being mention for emulsion. So how come some just use 1 surfactant?
2) Where do I dissolve the surfactant for O/W? For example, Tween 80 and Span 20.
Is it all in water? Or is Tween in the oil phase and Span in water phase? Or is it only after dissolving maltodextrin in water or before dissolving maltodextrin?
Are there specific steps I should follow?
I've been googling but I can't really get any answers. Sorry for the stupid questions.Thanks guys for the input!
Will try out in the labFollowing