Science method
Crystallization - Science method
The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Questions related to Crystallization
Is it a good idea to try to achieve binding of my protein to a ligand by soaking, even though the Kd of the interaction is in the mM range?
I have many drops with the crystallised apo-protein from the optimisation that form nice single crystals, unfortunately using the same conditions again but with the ligand for co-crystallisation I do not have crystals for all ligands.
Would it be a good idea to test soaking with the native crystals by putting them in the same solution + an excess of ligand (around 50mM)?
Do you have any suggestions?
I have purified protein using affinity and ion exchange, in both of the buffers i used ph of 7.9, while concentrating in buffer exchange, i changed the ph to 7.5 and concentrated upto 5.4 mg/ml and set up for crystallization. will the change in ph affect the crystallization process ? my protein ideal ph is 7.4
Hello every one,
I have seen somewhere that there is a critical size for ceramic additive particles (specifically BG) for making composite with semicrystalline polymer (specifically PCL). Above that size, the polymer's crystallinity increases and below that size, the polymer's crystallinity decreases. Is there any reference describing or proving this phenomenon?
I am trying to cocrystalize my protein with a sugar ligand, for this protein in particular I obtain only clusters, I tried to play around the pH( from 4,5 to 8,5) using the condition with clusters but nothing. I am wondering if I need to perform an SEC on my protein to get rid of some contaminants that can affect my crystallization. If you have any suggestion that can help me, I will be happy to try.


solution mediated transformation of calcium sulfate dihydarate to hemihydrate
"I am trying to crystallize my protein, Pqsd, and have several attempted to , but I have not obtained crystals. use screen jcsb plus, PACT, SG screen, Structure screen etc.
Here are the conditions I am using:
- Washing Buffer: 300 mM NaCl, 25 mM Tris (pH 7.5)
- Dialysis Buffer: 150 mM NaCl, 20 mM Tris (pH 7.5), 1 mM EDTA, 1 mM DTT
I have purified the protein, but despite multiple trials, I am unable to obtain crystals.
Key Information:
- Protein concentration: [7mg/ml to 10mg/ml]
- Temperature: 20°C.
- No crystals are forming, and I’ve tested multiple conditions.
Could you help troubleshoot what could be causing the lack of crystallization or suggest alternative approaches? Specifically, should I modify my buffer composition, or try other crystallization techniques or screening conditions?"
RNA isolation from the plant leaf samples.
There is no specific range i got from DSC analysis. I searched in many research papers but still didn't get any clue about possible defending reason for crystallization temperature ranges between 250 to 320°C.
It's urgent
Technically, Cold crystallizaion and Heating crystallization is measured, seperately and have differnt value. Some materials found Tc(Heating crystallization) but not found Tcc(cold crystallizaiton) in DSC analysis
I would ask Which thermal behavior makes two values different?
As far as I know, the shift of Tcc peak to right means the enhanced crystallization rate.
Then, I would like to know if the shift of Tc to right means decreased crystallization rate or not.
I am reaching out to inquire about water benchmark values for specific processes within the potash industry, namely carnallite decomposition, sylvinite washing, and vacuum-cooling crystallization. As part of my research, I am interested in obtaining water benchmark values expressed in cubic meters of water per ton of potash product. I would greatly appreciate any insights or data you could provide on this matter.
Additionally, I am seeking water benchmark values for the phosphate mining industry, specifically expressed in cubic meters of water per ton of rock phosphate product. If you have any information or resources related to water benchmarking in the phosphate mining sector, I would be grateful for your assistance.
Furthermore, I am interested in exploring water benchmarking software for the potash and phosphate mining industry. If you are aware of any software solutions or companies offering such tools, I would appreciate your recommendations or insights.
If you are unable to assist with my inquiries directly, I would be grateful if you could direct me to any relevant information sources, publications, or industry contacts where I may find the information I am seeking. Many thanks.
My initial attempts to separate the diastereomers through crystallization were unsuccessful. Since diastereomers have different physical properties, I was thinking of making the different forms and screening with different solvents to at least to enrich one. Among the different forms one is making the hydrated form and go-ahead. Since my molecule is amorphous in nature, even XRPD didn’t differentiate between anhydrous and hydrous.
I am working on a variety of DNA and RNA structures (generally quite short 20-40bp) and I have seen some worrying results around stability. I understand the nature of the solution will affect the structures ie ice crystallization, pH etc but I was just wondering what others have used and why? Obviously there's Glycerol, trehalose etc any off the shelf solutions others can recommend before I spend the money?
Thanks
I want to know about the fundamentals of dating magnetite, how magnetite can be used for geochronology, and the methods and instruments used for measuring the time of magnetite crystallisation, especially in sedimentary iron deposits like banded iron formations (BIFs).
Hello,
I am trying to estimate the thermal expansion of a semi-crystallin polymer (PEEK) with different degrees of crystallization. I couldn't find any rescources on this topic. Did somebody also encounter this specific problem? I'm just trying to get some orientation on how the degree of crystallinity effects thermal expansion to model it with isotropic material data.
Kind regards!
Hi everyone!
my protein crystals like as follow(picture1),aithough they can grow bigger,but seem not to be a single crystal, and without good three-dimensional forms. how should i optimize them? could anyone give me some advices?
thanks!
my crystallizton condition are as follow:
protein concentration :10mg/ml
drop ration: 1:1
temp: 4 ℃
crystallization buffer: 0.1M Tris-HCl,0.2M(NH4)2SO4、25%PEG 3350、1mM NiCl2


Hey so far i know that usually to calculate the percentage crystallinity of a polymer sample the enthalpy of melting is compared to the one of a theoretical 100% crystalline sample of the same polymer. My melting peak is very broad and probalby influenced by other factors aswell, my crystallization-peak however has a very clear start and end point.
That is why i want to use the crystallization-peak instead of the melting peak. I also know that the delta H of crystallization and of melting of the same polymer sample is usually not the same.
My additional question is, is there some sort of relationship between those two? For example the crystallization peak is the melting peak times a material constant or something like that?
I feel like the values will not be that comparable if i dont use the melting peak for the calculation can someone help me out?
I put a screenshot of the heating cycle (red curve) from -70 to 220 degrees and the cooling cycle (blue curve) from 220 to -50. Both at 10K/min.

I frequently observe that any ruthenium complex that is crystallized turns into an oily, sticky substance. Additionally, the surface of crystals frequently has some depositions. How can this be resolved?
why poly lactic acid doesn't have crystallization point in DSC
A first order approximation of nucleation and growth, Avrami equation can be generalized to higher and fractional dimensions with knowledge of volume and surface area of hyperspheres as well as Gamma function. Experimentally fitted fractional dimensions of Avrami equation is interpreted as predominant dimensionality of growth dimension (e.g. dimension 2.3 means mainly two-dimensional growth of crystals with somewhat inclination to three-dimensional growth), but can the same be interpreted as fractal dimension and hence an indicator of self-similarity scale for crystal growth? What is standard interpretation of avrami equation with dimensionality higher than three if experimentally found?(with explanation)
In this discussion, the dimensionality of growth of avrami equation is value of n-1 in
ln(-ln(1-Y))= ln K +n ln t
So I've been sorting through a collection of old microscope slides once used for teaching. I came across 12 slides of cockroach mouthparts mounted in what I believe is Canadian balsam, but they've gone completely opaque. The slides look a bit sparkly, so maybe some kind of crystallisation has occurred, but under the microscope it looks like a mess of fibres. We have hundreds of slide mounted in Canada balsam but no others look like this. I have no other information about the slides but I know nothing new has been added to this collection in at least 10 years so they are likely much older. I'm more curious than anything, does anyone have any ideas what might have happened?


Have I taken my area correctly to find the enthalpy of fusion Hm , so here the percentage crystallinty be Hm/Hm0 or i should consider the peak before the melting peak also and use the Hm-Hc/hm0 formula . Is this an example of cold crystallisation ?

- New PLA-based materials need to be developed to allow a good balance between environment-friendliness and product properties for engineering/durable applications.
- The blending of bio-based, brittle, and mostly amorphous PLA with semi-crystalline PAs (bio-sourced (e.g., PA11), or not (PA12)) has been reported to lead to high-performance materials (toughness, ductility, increased HDT and better thermal resistance, others).
- The low crystallinity of PLA is believed to strongly influence its final properties and to limit the applications of PLA-based products.
- Why not, the use of PLA (NA/nucleating agent) with high crystallization ability, to tune up the properties of PLA/PA blends !?
- Our paper aims to show the experimental pathways followed to produce novel PLA/PA blends using PLA(NA) characterized by improved crystallization kinetics (impressive degree of crystallinity). Moreover, it highlights with the possibility to tailor the morphology and properties of PLA/PA blends with special compatibilizers, such as epoxy styrene-acrylate oligomers.
Murariu, M.; Arzoumanian, T.; Paint, Y.; Murariu, O.; Raquez, J.-M. and Dubois, Ph.
Engineered polylactide (PLA)–polyamide (PA) blends for durable applications: 1. PLA with high crystallization ability to tune up the properties of PLA/PA12 blends, European Journal of Materials 2022, DOI: 10.1080/26889277.2022.2113986
The authors would like to share this contribution and have your opinion about the approach developed in this paper! Thank you.
(NB: Paper available open access, European Journal of Materials, Taylor & Francis Group https://www.tandfonline.com/doi/epdf/10.1080/26889277.2022.2113986?needAccess=true&role=button).
If a doped a material in a matrix. Its glass transition temperature and crystallization temperature decreases compared to the matrix but activation energy increases (Kissinger, Moynihan). Please give me the explanation for increased activation energy with decreased Tg and Tc.
Hi.
I am working on the Raman spectroscopy for cancer cell lines.
For that, we seed cancer cell on the CaF2 window , fix it and contains it in the PBS. We observe the cells without coverslip.
When we see the cell in the PBS, it was fine but after taking it out of the PBS and drying, it seems like the pictures below: some crystallizations and something black dots? on the cells
What I was thought is, it is the dried salt from the PBS but I'm not sure.
So my question is
1. What is the reason in the picture below happen.
2. What should I do if I want to avoid question 1. problem?
3. Is there anything special procedure needed for the cell sample without coverslip?
Thank you



I have a DSC result run from -90oC to 100oC in a heat/cool/heat cycle.
Tg, crystallisation and melting peaks are observed in the heat run. However the cool run, the crystallisation peaks are not reflected. What is the course of this from the polymer?
Solvent System
crystallisation technique
Dear colleagues! Have you ever studied Zr52.5 Cu32.5 Al10 Fe5 ? Could you share your experience if you have? I am interested in its phases.
I am studying the crystallization of this alloy from an amorphous state when heated, I cannot decipher the XRD analysis.
Why does Nylon, like Polyamide 66, have higher crystallization temperature after processing? We have tested the DSC (cooling rate: 20℃/min) of the Neat Polyamide 66 chips (without additives), the DSC shows the crystallization temperature is 208℃, but after extrusion or injection molding, the DSC results of the extrudates or injection molding bars show the crystallization temperature up to 230℃. Is this because of the reduction of the molecular weight after processing? But we have test the relative viscosity before and after processing, and show no significant difference.
Hi all, I set up the crystallization of protein-DNA complex for initial screen and found one crystal cluster appeared in a condition (0.1M HEPES pH7.0, 0.2CaCl2·2H2O, 45% MPD). Afterwards I added 10% glycerol and seed to optimize the crystal but it still turned out crystal clusters. How can I improve it into regular single crystals?

"I am conducting a study on PLA/PCL blends and need to determine the crystallization temperature of PCL using DSC data. Which cooling cycle data should I select to obtain this information, the first or second?"
In many research articles, it has been observed that 50/100/500 mL of solvent is commonly used for synthesizing metal oxide nanoparticles. While the metal precursors are soluble in a lesser volume of solvent than the amount used, it remains unclear why more solvent volume is used than what is necessary to dissolve the metal precursors.
Are there any correlations between solvent volume and supersaturation, nucleation, crystal growth or Ostwald ripening in nanoparticle formation?
My compound is soluble in THF ,DCM and Toluene .I am doing small scale crystallization in 5 ml vial taking 10 -20 mg of solid compound in each vial. I have already tried THF, THF/Pentane, DCM, DCM/Pentane, Toluene, Toluene/ Pentane combinations. In case of Toluene, I am getting ppt. In case of THF and DCM, even after 2nd and 3rd pentane layering I am not getting anything, not even ppt. Now what could be the solution ?What are the things that I should try ? I will highly value each of your suggestions.
Except adding a small amount of oxygen or increasing the pressure of the growth atmosphere, are there any other methods to inhibit the volatilization of Ga to maintain stable crystal growth conditions?
The crystallization procedure has different stages like induction, transition, and crystal growth.
hi everyone
I have simulated crystal growth in population equations with constant growth rate by Fluent, my results are bad. In the log-normal number density diagram, the value at the peak is smaller than the standard and is created faster than the specified time. Can anyone help me?
Hi all!
Is anyone aware of a model protein that crystallizes, albeit slowly? (~3-6 weeks)
I am looking to test activity of my crystallized protein so I am interested to know weather protein can be extracted from crystal state without damaging the viability of particular protein? and how it can be done?
Looking forward to receive helpful suggestions.
Thanks
Hi all,
I am looking for references about measuring crystallisation and metling enthalpy of pure water with differential scanning calorimetry (DSC).
Although this seems to be quite a straightforward job, are there any challenges associated with it?
Moreover, how can the presence of ions/proteins/biological membrane fragments, dissolved in water, affect the enthalpy of those phase transitions?
With many thanks
Best
Filippo
I isolated a crystalline solid that appears to be a sugar. I need to purify it but I cannot recrystallize it because it is only soluble in water. When concentrating it, it always ends up becoming a molasses and never crystallizes. Its not sucrose or any other common monosaccharide.
How could I achieve recrystallization of this solid?
self‐assembly in the crystalization process.
The origin and the first study in the field of self‐assembly
Here, this is the method :
"D-Fructose (2.16 g) is dissolved in water (4 ml) at room temperature. Boric acid (0.372 g) is then added to the thus prepared Solution, and upon its dissolving calcium carbonate (0.246 g) is added in Small portions. After carbon dioxide evolution has ceased, acetone (99%, p.a. quality; 20 ml) is added to the reaction mixture, whereupon a colorleSS oil Separates at the bottom of the reaction vessel. Two layers are separated using a separatory funnel, and the lower layer (crude boron complex) is treated again with acetone (20 MI). Upon standing at room tem perature for one hour, the mixture is triturated using a glass rod to induce crystallization, and the oil slowly Solidifies. This produces a white crystalline solid. "
I did exactly the same things written here but crystallization never occurs. Any idea ?
Hi everyone, I'm trying to crystallize a truncated DNA-binding domain of a transcription factor (Nuclear Factor I X) but its DNA-binding affinity is not optimal, therefore the complex is not very stable and its crystallization is quite tricky. I was wondering if there is one or more compounds that are known to favour DNA-protein interaction in such a way to promote complex formation and to make it more stable.
If you need more informations to answer this question, please just ask. Thank you!
Hey guys. I'm working with speed vac at the moment. But I don't know if it's the best way to concentrate the sample.
Another question is whether it is normal for the sample to become viscous when more concentrated.
One more question: sometimes the sample becomes saturated with other components of the buffer when it reaches a certain concentration. Can I dissolve it with water to undo the precipitation? Is there quantitative or qualitative loss of protein when it occurs?
Two pieces filled (by inner CaCo3 crystallization) that look like: either two vertebrae or a calcite filling of karst veins. Can you give your opinion on these two forms of fossil or mineral?


My DSC curve (Figure1) do not show a horizontal shape. It may be related to the calibration, even though we recently calibrated the instrument.
In any case, the software offers an option in the settings tab: DSC/DTA Horizontal on/off (Figure 2). Using this mode, the curve changes to what I would expect and what is reported in the literature (Figure 3). Does this setting affect my analysis (glass transition, ...)? Can I rely on this setting to perform my analysis?
The glass transition isn't clearly visible in my curve (Figure 1), but when I apply DSC horizontal mode, I can clearly see it (Figure 3).
If I can use this setting, how/where should I set the segment (Figure 4)??



I am synthesizing coumarin-3-carboxylic acid but products are not pure. I have done crystallization to purify them , they are still impure .Besides GC and HPLC , what other techniques should I use for purification.
Hello, i did H&E staining using cryosection.
However, there are so many holes in myofiber.
Here is my protocol.
No fixation for myofiber staining
1. Dissection - skeletal muscles
2. Embed into O.C.T using liquid nitrogen
3. After completely frozen, stored at -80c before using
4. Put it into -20c cryostats 20 mins before sectioning.
5. Cut to 10μm thickness
However, it is really hard to cut without getting holes, even though the blade is brand new.
Is the problem of water crystalization or freezing time?
Please help me.
I am performing experiments with optical cryomicroscopy. My samples seem to get crystallized upon cooling at -110 degrees celsius. Also, I am able to see some crystal structures when I freeze a thin layer of the sample.
But when I passed the cross polarised light through the frozen droplet of the sample I am not able to see any image. As seen in previous articles if the sample is crystallized, I should be able to see a bright light with the structure of dendrite formation in the droplet by using the cross polarised light.
So maybe my sample is amorphous and some amount of crystals are growing on top of it as it is very concentrated (around 50 Wt%) or it is homogenously freezing?
Where the solution was mixed at different hours
We put titanium dissopropoxide bis (acetylacetonate) in a freezing section for 1 day. Now the chemical is crystallized and segregated with the solvent. It won't go to a mixed state by itself. What do we do to recover the chemical?
In the literature three crystalline forms (alpha, beta and gamma) have been reported for PLA. As I learnt they have different crystallization behaviour. Using the DSC technique, with a 'heat-cool-heat' programme in some samples, during cooling, I am observing a 'double peak' of crystallization, may it be connected with different crystal morphologies in the case of alpha and beta or what it can be? While conducting an experiment with quench those are not observed in cold crystallization. Also I'm not sure am I on the right way of understaning this. Thank you.

I need some literature about the role of ammonia in the vs2 crystal growth during the hydrothermal process. Can anybody help? Thanks
What is the concentration of the surfactants used in the protein isolation, purification and crystallisation of proteins and what is the basis for selecting the surfactant concentration in the different steps in proteomics?
After synthesis, I kept it for crystalization in the oven for 5-7 days. I have a few questions related to this:
1) Does sonication time affect the edges of MOF
2) at what stage do we take samples for TEM: after synthesis or after crystalization
3) Amount (weight) of MOF used to prepare the TEM grid
When I was growing a single crystal recently, I found that the flux Sn residue on the surface of the single crystal was very serious. I repeated centrifugation, but it still didn't seem to work. I then soaked the single crystal with dilute hydrochloric acid (10%), but the single crystal is corroded. I think I should further improve the crystal growth process, so I wonder if there is any special way to overcome flux residue during crystal centrifugation. If you know, please let me know, thanks a lot.
Is there any optimum quantity of cristobalite (in terms of percentage) for a silica-based core to meet the requirements of turbine blade investment casting? How can I control this crystallization process?
In social drinking scenarios, my preference has always been "on the rocks", but the ex/in-plosion mentioned in the title is quite new to me. I feel it's due to unusual crystallization or air trapped or whatever, as I pour water on remnants of broken ice in the tray. Can anybody give me a scientific explanation of it?
Thanks.
Hi all,
I'm working on a protein complex crystallization. Luckily, I got some large thin layer crystals in following condition (Na cacodylate, ~10% PEG3350). However, when I tried to harvest these crystals, I found that they are very soft (just like the SDS PAGE?). Does anyone have the similar experience?
Btw, I have tried different temperatures, various PEG compositions and even additive screening, but I failed to obtain any better crystals (no diffraction pattern). How can I optimize the condition?
Thanks in advance.
Here is the crystal(?) image:

One of the main hurdles which prevent the wide-scale adoption of cryonics as a valid medical technology is the issue of water crystallization in cells which lead to cell rupture. Have there been any advances made in literature recently to address this issue? Would appreciate links to survey articles, if available. Thanks
What is the type of nucleation in Polypropylene composites containing carbon black (less than 3 wt.%) during crystallisation and recrystallisation?
Is it homogeneous, heterogeneous, secondary nucleation?
Specifically in the laser transmission welding process.
Recently I stored two samples (Cell culture supernatant) collected on two consecutive days ( i.e. day 5 and Day 6) and stored in -20 0C, But after 7 days when I saw the samples, One sample is crystallized (as expected due to low temperature) but whereas other sample is still in liquid state, I'd like to know the possible reason for this ?





Hello,
I am trying to fit the atom. I tried to match PEG to density, because my crystallization condition contains PEG. But I can see the appearance of negative density after refinement. What other atom I should try ? The Electron density map is attached.
Thanks

my peptide molecule having free acid and gunidine group ,How can we crystallize and what are the best solvents for crystallization ?
Hello everyone,
I am looking for fundamental level book for crystallization and its controlling parameters.
Could you please suggest any good recommended book ??
Please note: My area of research is *Struvite recovery from waste water* ?
Many thanks
How to extract peaks from X-ray test to calculate the crystallization ratio% of the material
As well as the size of the crystal.?
When examining X-ray diffraction of any material, are you given the standard to x-ray with the examination?
Dear all
what is the new and HOT promising diluted magnetic semiconductor materials, that can have ferromagnetic and semiconductor properties close to room temperature? Wich not very difficult to realize (based on typical crystal growth techniques, availability of source)
My question is directed for research purposes, not necessarily for commercial applications.
Please share your knowledge. Additionally, If you know a good paper for this question, please tell me.
Thank you in advance.
Best regards.
Ismail
Hi, recently I tried to do crystallization of a transaminase from Serratia sp. however, when analyzed I couldn't find Schift base or substrate in the active site nearby putative active site (K residue), but found PMP thus I predicted that the substrate was reacted during preparation and released as keto-amine. I was told that PLP-Glutamate or whatever amino acid can be synthesized before being mixed with protein before crystallization to make it observed in the structure. If you would like to share how the protocol for producing PLP-AA, it would be really appreciated. Thank you
We know that amorphous polymers having the potential to crystallize can show peaks at DSC heat flow diagrams. The question is, does a polymer such as PLA, PET, etc. with a little amount of crystallinity (lower than its potential) show the same cold crystallization behavior?