Microspheres Online

Everything about microspheres and research utilizing precision spherical particles.

Microspheres in Cosmetics – Solid Polymer Microspheres for Color Effects

A recent article on microspheres in Cosmetics & Toiletries magazine describes the use Solid Polyethylene Mirospheres for Effects in Color Cosmetics. Microspheres have been used in cosmetics for some time, primarily as fillers and exfoliators. Most recently scientists started to utilize light reflecting properties of microspheres for creating unique optical effects, such as optical blurring … Read more

Cosmetic Applications of Injectable Polymer Microspheres

Polymer microspheres, in particular injectable polymer particles with a diameter in the range of 30-300um, are becoming widely used as a biomaterial in different clinical fields, such as cosmetic surgery, reconstructive surgery, and urology. Injectable skin fillers offer many benefits in cosmetic dermatology, allowing new forms of facial rejuvenation and wrinkle treatment without surgery. Injectable … Read more

Motivations for Using Biodegradable Microspheres in Drug Delivery

In recent years there is significant interest in using biodegradable polymeric microspheres for drug delivery. Delivering drugs through biodegradable microspheres has numerous advantages compared to conventional delivery systems. While in conventional systems the drug is usually released shortly after delivery and stops working after a brief period of time, biodegradable polymer offers a way to provide sustained release over a longer time, thus eliminating the need for multiple doses and ensuring sustained and controlled drug delivery over weeks or months.

Porous Ceramics: Application for Polyethylene Microspheres

Background:

Usually porous ceramics are made from aluminum oxide, silicon carbide or Zirconia.? Most porous ceramics have a natural ability to fill pores by capillary action. This makes porous ceramics water accepting, thus they also are referred to as hydrophilic material. This means the pores and channels of a ceramic have a highly charged pore surface that attracts and bonds the polar molecules of water and other polar fluids. The net effect is called “wicking” — the ability to pull fluids into the material and transport that fluid by capillary forces.? The pore size directly affects the ceramic’s air entry or bubbling pressure and hydraulic conductivity. The effective pore size is determined by the minimum orifice within a channel or pore.1

Some porous ceramic have 40-50% open porosity with a tortuous pore structure and is available in pore sizes ranging from 0.25 to 90 microns. Monolithic, single grade, aluminum oxide porous ceramic is available in 6, 15, 30, 50, 60 and 90 micron pore sizes. In addition, some ceramic membranes can use a medium pore substrate with a thin coating of fine porous ceramic membrane in 0.25, 1, 3 and 6 micron pore sizes.2

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Dual nanocomposite multihollow polymer microspheres prepared by suspension polymerization based on a multiple pickering emulsion

Excerpts from an interesting approach to creating hollow polymer microspheres from a pickering emulsion.

Abstract:

A solid-stabilized multiple w/o/w or o/w/o emulsion was prepared in a two-step process. Various nanocomposite polymer microspheres with multihollow armored closed pores were fabricated easily by suspension polymerization of the multiple Pickering stabilized emulsions.

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Measurement Techniques for Electrostatic Charged Microspheres

Charged Microspheres Measurement TechniquesElectrostatic charge (also known as triboelectric charge) on microparticles and microspheres have been of interest to scientists in chemical, pharmaceutical, cosmetic, drug delivery, displays and other industries for many years. Until recently there were no reliable techniques to measure or quantify electrostatic charge on microparticles, with too many uncontrolled variables the measurements were inconsistent. As a result scientists were treating charging as a black box process, performing the experiments blindly as trial and error. With recent advances in microsphere manufacturing, techniques have been developed that promise not only to quantify the charge on microspheres, but control it in the manufacturing process.

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Electrostatic-based DNA Microarray Offers Medical Diagnostics Capabilities

The uses for microspheres continue to grow, a recent article published by UC-Berkley shows how DNA sequencing can be achieved through the use of statically charged microspheres. ? The key breakthrough is that they have been able to achieve a visible result through using the electrostatic repulsion of the microspheres. ? A copy of their announcement follows:

Groves,? and members of his research group Nathan Clack and Khalid Salaita, have published a paper on their technique in the journal Nature Biotechnology, which is now available online. The paper is entitled “Electrostatic readout of DNA microarrays with charged microspheres.

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Microspheres for Coatings Applications (Opaque Polyethylene)

Microspheres are well known in the coatings industry for their use as low-surface-area fillers that offer benefits in viscosity and density control, solids content, application and flow characteristics.

Hemispherically Coated Spheres

Cospheric LLC, a Santa Barbara-based microtechnology company, recently launched a line of opaque polyethylene microspheres that act as a superior opacifying agent and provide maximum hiding power with just one monolayer of microspheres as small as 40 microns in diameter. Microspheres are manufactured in any color imaginable and even in combinations of two differently colored hemispheres.

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Chitosan microspheres prepared by spray drying

Spray drying has been used in the production of fine powders from emulsions for many years, but it is not a process in which most people associate the production of microspheres.? This journal article shows how the authors were able to produce highly spherical microspheres in the 2-10um range by controlling the levels of Chitosan and crosslinking agents used.

Chitosan MicrospheresThe key items I found of interest in this article were:

The quality of the microspheres that were produced, as seen the the attached SEM micrograph.

How the process variables did not affect the zeta potential of the microspheres produced (Table 4 below), and how the size can be varied by varying the concentrations of Chitosan or the Molecular weight (MW).

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Fluorescent Tracer Microspheres – Properties and Applications

Fluorescent Tracer Particles

Fluorescent microspheres are round spherical particles that emit bright colors when illuminated by UV light. Ability to emit intense color under UV (black light) illumination provides contrast and visibility of microspheres relative to background materials.