Microspheres Online

Everything about microspheres and research utilizing precision spherical particles.

Fluorescent Glass Microspheres

Fluorescent Red Coated Soda Lime Glass Microspheres

Solid glass microspheres hemispherically coated with fluorescent coatings, a fluorescent coating is precisely applied to half of the core sphere, making the glass spheres appear colorful and fluorescent at daylight and exhibit bright fluorescent response under UV light.

Silane and Fluorochemical Coated Glass Spheres

The following products are offered in both Silane and Fluorochemical Coating.
P2011SL 3-6um mean diameter solid soda lime glass
P2015SL 8-12um mean diameter solid soda lime glass
P2050SL 35-45um mean diameter solid soda lime glass
P2075SL 65-75um mean diameter solid soda lime glass
P2453BTA 40-60um mean diameter solid barium titanate glass with aluminum shell.

High Density Glass Microspheres

Barium Titanate Glass microspheres are high density solid glass spheres. At a Density of 4.5g/cc these solid glass spheres can be used for many scientific applications where high density and optical clarity is needed. In addition to high density they also offer an index of refraction of more than 1.9.

BioCompatability of Metal Coated Spheres

For those scientists?who are looking to use silver coated materials?such as silver coated microspheres in biomedical applications, it is important to understand whether they are bio-compatable.? A selection of abstracts and article references related to the biocompatability of silver follow:

The Biocompatibility of Silver2

The experiments reported have referred to some of the characteristics of the biocompatibility of Ag. Silver has been shown to display interactions with albumin, as an example of a plasma protein, quite different from those of most metals. Such studies shed further light on the complex issue of protein adsorption on biomaterials. It has also been demonstrated that Ag at concentrations < 1 ppm exerts a considerable influence on the activity of lactate dehydrogenase, this effect being reversed in the presence of albumin. A significant but transient increase in blood levels of Ag following intramuscular implantation of the metal has been observed. This is not reflected in any raised urine level. It is proposed that the richly vascular tissue immediately surrounding the implant in the acute phase of the response gives rise to the transient increase, but a subsequent decrease in vascularity reduces this possibility. It appears that Ag released from implants following this initial period substantially remains in the local area.2

Lack of toxicologocial side-effects in silver-coated megaprostheses in humans1

Deep infection of megaprostheses remains a serious complication in orthopedic tumor surgery. Furthermore, reinfection gets a raising problem in revision surgery of patients suffering from infections associated with primary endoprosthetic replacement of the knee and hip joint. These patients will need many revision surgeries and in some cases even an amputation is inevitable. Silver-coated medical devices proved their effectiveness on reducing infections, but toxic side-effects concerning some silver applications have been described as well. Our study reports about a silver-coated megaprosthesis for the first time and can exclude side-effects of silver-coated orthopedic implants in humans. The silver-levels in the blood did not exceed 56.4 parts per billion (ppb) and can be considered as non-toxic. Additionally we could exclude significant changes in liver and kidney functions measured by laboratory values. Histopathologic examination of the periprosthetic environment in two patients showed no signs of foreign body granulomas or chronic inflammation, despite distant effective silver concentrations up to 1626 ppb directly related to the prosthetic surface. In conclusion the silver-coated megaprosthesis allowed a release of silver without showing any local or systemic side-effects.1

Specific Article?References for the biocompatability of silver are below:

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High Index of Refraction Retroreflective Glass Microspheres

Barium Titanate Glass Microspheres are excellent for use as a functional retro reflective additive to paints and coatings. Spheres with sizes of about 50 micron (~0.002 inches) mean diameter provide a small enough size for most coatings while offering a large enough size to reflective a significant amount of light. Barium Titanate Glass Spheres are offered in both partially aluminum coated retro-reflective version for addition into transparent coatings, or as uncoated glass spherical powder for uses in colored paints.

Patent Review: Process for forming hollow glass spheres up to 5mm

A process for forming hollow glass micro-spheres with walls of controllably variable thickness in a size range of 50 to 5,000 microns, embodying (1) preparation of a water slurry of finely particulated, high temperature and low temperature glass formers; (2) prilling the slurry in a vertical spray drying tower; (3) separating and supporting the individual prilled feed material; (4) heating the feed material to glassification of the high temperature glass former while maintaining appropriate geometry and shell thickness and (5) cooling the finished product. The high temperature glass former is preferably a naturally occurring soda feldspar. The process is particularly adapted to form thicker walled micro-spheres of larger size and high quality.

Advantages of Borosilicate Glass Microspheres in 0.03mm to 0.2mm sizing

Borosilicate Glass Microbeads
BSGMS 63-75 micron at 40x magnification

High quality glass microspheres for research and development are always in high demand.? In an effort to better serve scientists Cospheric recently added a complete line of high quality borosilicate microspheres, and microbeads.

Borosilicate glass offers? advantages over standard soda lime glass microbeads.

  • Roundness is >90%?? (Soda lime >85%)
  • Density is the lowest of most glasses at 2.2g/cc? (Soda Lime 2.5g/cc)
  • Very low thermal expansion coefficient? 32×10-7/?C?? (for 30-300?C)?? (Soda Lime:? 90×10-7/?C)

The high roundness, and low thermal expansion make borosilicate spheres an excellent candidate for use as spacers in epoxy bond lines, or other applications which require stability over a wide temperature range.

Borosilicate glass spheres are now offered in narrow size ranges from 0.03mm to 0.2mm with greater than 90% of the particles in range.

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Monodisperse – Spacer Grade Microspheres

Scientists are constantly looking for narrower particle size distributions (monodispersed) of microspheres to help increase the consistency and correlation between theoretical models and verification experiments.? In an effort to fill the increasing demand for these particles Cospheric has launched a new line of spacer grade microspheres. Monodisperse microspheres are currently offered in diameters of:?? 21-24um, … Read more

What is a Microsphere? Definition and Explanation.

Sourcing Microspheres - Monodisperse Silica
Conductive Bondline Spacer - Silver-Coated Silica Spheres
Conductive Bondline Spacer – Silver-Coated Silica Microspheres (Cospheric Product ID: SiO2MS-Ag)

Definition of a Microsphere:

There is a lot of confusion and uncertainty in the academic community as well as the industry on exactly what is a microsphere. Below is the definition of “microsphere” that we use, because it is clear and straight-forward:

Microsphere is a term used for a small solid spherical particle, with diameter in the micrometer range (typically 1 micron to 1000 micron (1mm)).

What a Microsphere is Not:

A microsphere is not the same as a microcapsule, because microcapsules typically consist of a flexible (deformable) shell encapsulating a fluid, which might be liquid or gas. Microspheres always have a solid shell. Even if the microsphere is technically hollow (containing gas inside), its shape is not significantly flexible or deformable.

A microsphere is not the same as a microparticle, because microparticle is a general term that refers only to the size of the granular material and does not provide information on the shape. Microspheres are always round and spherical. There are no sharp edges, oblong shapes, or debris.

What are Nanospheres? Silica Nanospheres
Monodisperse Silica Nanospheres (Cospheric Product ID: SiO2MS)

A microsphere is not the same as a nanopshere, because nanospheres have diameters on the nanoscale (typically between 1 nanometer and 1000 nanometers (1 micron)). Nano-diameters present a complete different characteristics, behaviors, and functionalities.

What are Microsphere Materials:

Microspheres are manufactured from various natural and synthetic materials. Glass microspheres, polymer microspheres, and ceramic microspheres are commercially available. Solid and hollow microspheres vary a lot in density and, therefore, are used for different applications. Hollow microspheres are typically used as additives to lower the density of a material. Solid microspheres have numerous applications depending on what material they are constructed of and what size they are.

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