What Size of Soft Bead Should I Use?

This is a great question that has a long answer. We really wish there was a very clear, concise answer that we could confidently provide to answer that question. The shortest answer we could give you is, the largest size that you feel comfortable with that does not scare the fish. The larger the bead, the more visibility, the better chance that the fish will see it and then bite it. Some other variables to consider are discussed below.

Things to Consider When Fishing With Soft Beads

Target Species: What are we fishing for?

This consideration is one of the simpler ones. Larger fish, larger beads, smaller fish, smaller beads. For chinook and coho, beads from 16mm to 32mm are effective. For steelhead, beads sizes from 10mm to 20mm are effective. For trout, beads sizes from 8mm to 12mm are effective. Trout and steelhead can be especially selective about bead size being matched to the size of loose eggs that are currently in the river.

Visibility: How far can you see in the water?

One of the biggest benefits of larger beads is visibility. We think of the bead as an attraction beacon floating down the river. It tends to be very hard to catch a fish if the fish is unable to see your bead. The lower the water visibility is the larger bead you should feel comfortable using. The higher the visibility the smaller the bead. For steelhead in 4-8 feet of visibility a 12mm to 14mm bead is a good size to start with. For 2-4 feet of visibility at 14 to 20mm bead is good size. For visibility less than 2 feet 20mm is a good bead to start with.

Pressure: How much pressure have the fish seen?

We have all experienced those magical days. It just stopped raining after an extended period of high water, the river has dropped into shape, and it is the prime time of the season. The fish are fresh and have not seen a bait. It’s on those days that a large visible bead is very effective. What about those days when the river has been fishable for 2 weeks, slowly dropping a little lower each day? The visibility is getting better, and it feels like every steelhead fisherman you have ever heard of is fishing your chosen river? On those days the smaller more subtle beads are to your advantage. The fish have experienced a significant number of highly visible baits and the least offensive sized bead can be the best chance to get bit. In these cases, we recommend 16 to 20mm for salmon, 10 to 12mm for steelhead and 8mm for trout. In conclusion, we recommend the largest bead that you feel confident with.

What Color of Soft Beads should I use?

What color of any lure that we choose is one of the oldest questions in fishing. We are fairly certain that the first cave-fly fisherman thought long and hard about what feathers to tie onto their hand carved hook before heading over to the local lagoon. As you can see from the BnR Tackle bead selection options there are a lot of different colors to choose from. Most of the colors are color variations of red, orange and pink with some variations of chartreuse.

Targeting Salmon with Soft Beads

We recommend the boldest and the brightest beads when targeting salmon. The most effective colors tend to be Cerise, Mottled Red, Sweet Pink Cherry, Clown and Joker. These colors are highly visible to the fish. Some alternatives to this recommendation include: If you are fishing the bead as a dropper under bait and if lower water or high-pressure conditions exist. When fishing beads as a dropper 8 to 12 inches under bait, we recommend a color that is a distinct contrast to the color of your bait. For example, if you have a bright red egg cure, then a light pink bead or even natural bead would be a good choice. Under high-pressure conditions, more subtle colors are recommended. These options include Mottled Cerise, Creamsicle or Natural.

Salmon Bead Color Recommendations:

Targeting Trout with Soft Beads

When targeting trout the bead color selection can be the most difficult to choose. Egg-eating trout are resident fish who are used to eating the specific type of eggs that happen to be drifting out of the gravel. Trout can be much more selective about color than salmon and steelhead. We recommend looking at what other species of fish are actively spawning in the river. For example early in winter steelhead season there are a lot of fall chinook and coho spawning which tend to have red-colored eggs. For rivers in Alaska with pink salmon, orange or peach beads like Creamsicle and Shrimp are effective. Later in the winter when steelhead are actively spawning light orange beads like Natural and Peach Gobbler are effective. We also recommend considering when the whitefish or suckers spawn in the spring. These eggs tend to be green in color and the Hot Snot and Mean Green colors are effective.

Trout Bead Recommendations:

Trout Winter Bead Recommendations:

Targeting Steelhead with Soft Beads

For steelhead there color selection, consider that Steelhead can act like a Salmon and a Trout when it comes to color preferences. Steelhead can be very reactive to brightly colored beads like Cersie, Sweet Pink Cherry and Clown when the fish are fresh and the water conditions are higher and greener. When the water drops and the visibility increases steelhead bite well on more subtle, natural colors like Pink Sheen, Mottled Pink, Creamsicle and Shrimp. Also similar to trout, steelhead can show preference to bead colors that are comparable to to the eggs of the fish that are actively spawning in the river. For example, Red and variations of red are effective when chinook and coho are actively spawning.

Steelhead Soft Bead Recommendations:

Want to check out all of our soft bead options, head over to the soft bead shop page! 

Bead Selection Guidelines

For Cell Disruption, we suggest:

Size

• When wet bead milling Bacteria, use the 0.1mm diameter glass beads.
• When wet bead milling Yeast/Fungi, use the 0.5mm diameter glass beads or zirconia/silica beads.
• When wet bead milling Soft Tissue (e.g, liver, brain, muscle), use 1.0mm diameter glass beads or zirconia/silica beads.  When wet bead milling tissue, a sample size over a few tens of milligrams should first be pre-chopped into pieces less than 1 mm in cross-section before beadbeating.
• When wet milling Tough Tissue (e.g., Connective tissue, Skin, or 'non-woody" Plant material), pre-chop or cryo-pulverize first and use 2.0mm diameter zirconia beads.
• When working with Especially Tough or Fibrous Tissue, use the same-sized beads suggested above but choose a more dense bead material.  For example, use zirconia-silica beads for disruption of spores or three 2.3 mm chrome-steel beads for extraction of tough fibrous plant material like monocotyledon leaves.

The MiniBeadbeater can be used in a 'dry grinding' mode - either at ambient or liquid nitrogen temperatures.  For example, a single seed can be pulverized into a fine powder in 30 seconds using three 3.2 mm diameter or one 6.3 mm diameter chrome steel bead in the vial. Hair can be powdered when embrittled at liq N2 temperatures using similar-sized steel beads. Note that Dry grinding with steel beads requires special, reinforced polypropylene vials (see XXTuff microvials and stainless steel microvials).

How many beads are in a one-pound bottle?

Chrome-steel Beads:

6.23 mm diameter ~430
3.2 mm diameter ~3300
2.3 mm diameter ~7900

Glass Beads: Multiply by 3.2; Zirconia-Silica Beads: Multiply by 2.1; Zirconia Beads: Multiply by 1.4

TECH ADVICE re. Bead Combinations: Some vendors sell pre-filled microvials which supposedly contain unique combinations of different sizes and types of beads in the same vial. This is mostly marketing hype and comparative data to back up their claims of uniqueness or enhanced performance are not available. With few exceptions, measurable improvements in cell lysis derived from "magic" bead combinations are marginal. Save money by adhering to the guidelines above and loading vials yourself...a process that takes a couple of seconds per vial.  BioSpec has a "Do-It-Yourself" bead loaders described here. And, if you need to load hundreds of microvials or micro-plates, check out our stable of custom-designed Bead Loaders. If you would rather purchase pre-loaded vials, tubes, or microplates, BioSpec Products does that too.

Density

• Glass beads have a density of 2.5 g/cc and is the most common bead media used for 'Beadbeating'.
• Zirconia/Silica beads have a density of 3.7g/cc (50% denser than glass - good for spores and most tissues).
• Silicon Carbide sharp particles (not a bead) have a density of 3.2 g/cc (Thet may work faster on tough tissue samples because the particles have sharp cutting edges. Their superiority over less expensive Zirconia/Silica beads is under investigation.  But see Brein's comments below.
• Garnet (an iron-aluminum silicate, sharp particle) has a density of 4.1 g/cc. Like dense, sharp-edged SiC particles, it accelerates the lysis of tough tissue. Unlike SiC sharp particles, garnet particles fragment during beadbeating. This property can be useful when homogenizing soft tissue or fecal and soil samples containing bacteria.  No mix of bead sizes will be needed.  Starting with microvials half filled with 2 mm Garnet particles, the sample is rapidly dispersed.  At the same time, the beadbeating has produced, in situ, much smaller Garnet fragments which can efficiently disrupt the microorganisms.
  
• Zirconia has a density of 5.5g/cc (100% denser than glass) - This ceramic bead, used for tough tissue, is chemically inert and resistant to fragmentation.
• Chrome-Steel and Stainless Steel have a density of 7.9g/cc.  These heavy beads are most often used for dry-grinding leaves and seeds. Depending on the size of the bead, 1 to 5 steel beads are placed special reinforced 2 ml polypropylene microvials or 2 ml stainless steel microvials.  Ordinary screw-cap polypropylene microvials can crack or leak when used with steel beads.  Chrome-steel beads often are a good substitute for stainless steel beads.  While stainless steel beads are often selected because of their corrosion resistance, chrome-steel beads are inexpensive...indeed, they are cheap enough to be used as "disposable", thus eliminating cleaning and cross-contamination concerns.  One Caution: Eventually, chrome-steel beads will rust in contact with aqueous media.  They should be promptly removed from the cell lysate.  A small magnet provided by BioSpec when ordering chrome-steel beads makes that chore easy.
• Tungsten Carbide has a density of 14.9 g/cc.  While very dense, this bead is generally not used for biopreparations because it leaves the homogenate looking "dirty".  High g-force centrifugation will clarify the homogenate but that is time-consuming.  The other dense media listed above can usually do just as good a job.

Other Uses for Beads

• Quick and easy plating of yeast and bacteria.  Add a dozen or so sterile 6.3mm diameter glass beads to the solid nutrient media.  Shake the plate (or a stack of plates) using a sideways motion to evenly distribute the added liquid suspension of yeast and bacteria over the surface of the plate.  The beads can be poured off after the inoculum has penetrated into the media gel by inverting the plate and tipping the beads out of the lid.
• Increase the surface area for tissue culture growth by packing roller bottles, tubes, or vials with 6.3 mm diameter glass beads.  In this application, the beads should be tightly packed to prevent the movement of the beads during rolling or shaking.  Similarly, when growing cells in non-agitated culture flasks, a confluence is reached faster and cell density enhanced by adding a layer of 0.1 mm diameter beads [see Growth of Three Established Cell Lines on Glass Microcarriers by James Carani, et. al., Biotechnology and Bioengineering, Vol.25, p.1359-1372 (1983)].
• Create a bio-reactor by packing a column with glass beads and inoculating it with select surface-adhering micro-organisms or cells.
• Keep dialysis tubes vertical during dialysis by adding a few large glass beads or marble before sealing.
• Nanotechnology. Grinding of hard or friable particles to sub-micron size.  A short review "High-tech Ball Mills Spur Nanotechnology Advances"  contains practical information for bead-mill grinding of nanoparticles using a Retsch E-max™ bead mill.  The MiniBeadbeater series of bead mills extend this application to processing smaller amounts (<0.5g) of precious material.
• Lens for a Smartphone microscope attachment.  See the glass beads page.
• Replace water in commercial lab baths with aluminum beads.  No wet tubes to wipe, no tubes tipping over, no need for racks, floats, or weights.  BioSpec Products "Tiny Teardrops" aluminum beads provide superior thermal transfer to the tubes.  For details see Tiny Teardrops Aluminum Thermal Beads.
• Improved yields of viable single cells derived from animal tissue incubated with matrix-digesting enzymes.  Explore a novel application of plastic beads.  Replace tedious "manual trituration" of tissue fragments being lysed by digestion of the tissue's extracellular matrix with appropriate enzymes.  See a Development Proposal.
• Faster QuEchERS technique.  Make this popular protocol for extraction and analysis of small organics (cannabinoids, pesticides, herbicides, pharmaceuticals) from plants, animal tissue, and foods faster.  Halve the time for sample hydration and homogenization by including a few 2 -3 mm diameter glass beads in the extraction tube and vortex.  Or, better yet, increase throughput by homogenizing multiple extraction tubes in a MiniBeadbeater.

Applications

Feedback from Santhosh Chelian of UC Davis. "Fresh rice leaves or tree needles were powdered or pulverized with a MiniBeadbeater using several 2.3 mm or 3.2 mm chrome steel beads in BioSpec's Stainless Steel Microvials equipped with silicone rubber caps.  The capped vials contents were immersed halfway into liq. N2 and then quickly inserted into a MiniBeaterbeater.  No liq. N2 is added to the vial.  Pulverize for a one-half minute.  Refreeze and repeat for another 1/2 min, if necessary. Forty to sixty mg of plant material was used in each vial.  After cryo-pulverizing the above tissue, DNA or RNA extraction solution was added to the microvials with beads, and the mixture was "beadbeat" for an additional 1-3 minutes at room temperature.  Nucleic acids were recovered in high yield."

BIOSPEC NOTES:

Due to the very high shaking energies of BioSpec Product's series of Minibeadbeaters, dry milling with large steel beads can crack (or even escape from) common polypropylene microvials. This problem is exacerbated at cryo-temperatures.  To get around this, BioSpec stocks two kinds of 2 ml microvials specifically designed for use with steel beads:  "XXTuff" reinforced polypropylene microvials and Stainless steel microvials with silicone stoppers.  For MiniBeadbeater-96 users, we also stock reinforced Porvair deep well microplates.  Also available is a MBB-96 solid aluminum vial holder.   When it is pre-chilled to liq. N2 temperatures, this vial holder will maintain ultralow temperatures during the beadbeating process.

For the extraction of very high molecular weight DNA, tissue samples can be cryo-pulverized to a fine powder by either the above dry-milling method or a BioPulverizer.  Then follow by very gently rocking or swirling the powdered sample in a DNA extraction solution using a speed-adustable shaker like BioSpec Products' BioRotator-6. Minimize shearing is essential during this extraction step...no lab vortexing, no stirring rods, no stir bars, no repetitive pipetting.

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Freeze-dried leaf tissue or dry seeds can also be dry ground.  In this case, cryo-temperatures will not be needed during grinding.  Use three 2.3 mm diameter glass beads or a single 2.3 mm chrome steel bead per vial and beadbeat for 15 - 60 seconds.  When dry grinding with chrome-steel beads BioSpec's "XXTuff" reinforced polypropylene microvials or Stainless Steel microvials with silicone rubber caps must be used.

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Recent information suggests that plant and animal tissue can be disrupted with sharp-edged particles more quickly than smooth beads.  BioSpec Products stocks sharp particles of Silicon carbide or Garnet in three sizes.

Feedback: James Brien of Health & Science, University in Portland, OR. Brien reported that several whole organs from mice, cut into 3-4 pieces, was completely homogenized using 1 mm diameter SiC sharp particles.  His objective was to measure virus load using a plaque assay.  He found that the usual pre-chopping of the tissue to 1mm cross-section pieces was not necessary.  Using a dye permeability test, he estimated that better than 99% of the cells were lysed after 2 minutes of shaking in a Mini-BeadBeater-96.  Lysis in both 2 ml and 7 ml vials was tested. In both cases, one-half of the vial volume was filled with sharp particles.  Controls using similar loads of 1 mm diameter spherical glass beads gave poorer results.

BIOSPEC NOTE: A minor 'downside' on the use of sharp particles is that particles abrade during beadbeating and the cell homogenate will have a yellow-gray color.  This off-color is colloidal-sized grinding particles suspended in the homogenate.  Both SiC and Garnet are essentially chemically inert and the colloidal particles can be separated from the homogenate downstream by filtration, centrifugation, adsorption, or precipitation.

Additional Bead Information

• For faster filling of microvials and microplates with beads, see Commercial Bead Loaders and Do-It-Yourself bead-loading tools.

• Coating beads to be used for grinding is a waste of time.  The coating will quickly be removed by abrasion during shaking.

• Most bead media is reusable.  Wash used beads with lab detergent and rinse well.  For more on this see How to clean your beads.

Ordering Information

Most beads are sold in one-pound bottles with easy-to-use pour spouts.

Listed bead sizes are median (average) values.  Because beads are sorted by sieves, bead size varies between +/-10% of a listed value.

BioSpec Products offers PRELOADED beads in 2ml screw cap vials or 96 well microplates.  There are too many possible combinations of bead size, bead composition, and bead load to stock prefilled microvials or microplates.  We do this on a custom basis with a quick turnaround.  Tell us what you need at info@biospec.com and we will give you a price quote.