Microspheres to Measure Blood Flow

Technical Information

BioPAL's stable-isotope labeled microspheres provide the research community with a cost- effective alternative to the use of radioactive and optical microspheres for the measurement of regional organ blood flow and particle deposition studies.

The experimental method for using stable-isotope labeled microspheres is identical to the traditional radioactive method, differing only in the assay of the microspheres, which is performed by BioPAL. At the close of the experiment, tissue samples of interest are collected, weighed and placed in BioPAL's tracer-free polypropylene samples vials. If blood flow measurements are to be calculated (mL/min/g), then blood samples are sent to BioPAL for analysis, which uses neutron activation technology for the measurement of microsphere content. The researcher can expect the results of the assay within ten working days.

BioPAL's assay procedure is not chemically or physically destructive and the measurement can be repeated. Therefore, samples can be archived for future reference. The ability to re-assay stored samples is a major advantage for pharmaceutical development.

Non-radioactive microspheres to measure regional blood flow in preclinical animal studies and for angiogenesis research and perfusion studies.

The Product

Twelve different stable-isotope labels are available. Microspheres come in 10 mL and 20 mL vials containing approximately 2.5 million spheres per mL. The microspheres are 15 µm (standard size for blood flow studies) or 10 µm in diameter and are suspended in normal saline containing Tween 80 and 0.01% Thimerosal.

BioPAL's polypropylene sample vials are cleaned to remove trace contamination and are calibrated for our activation and counting system. These vials must be used for the assay.

SansSaLine, a saline-free buffer, as a substitute for saline or PBS in histochemical stains and for use to wash and clean samples in order to minimize sodium background activity, thereby maximizing the sensitivity of the measurement.

BioPAL charges a per-sample assay fee. The results of the assay are reported as the total disintegration per minute (dpm) measured in each sample for each corresponding microsphere label. BioPAL also will calculate the absolute blood flow (mL/min/g) measured in each sample for an additional assay fee.

Pricing Information

Stable-Labeled Microspheres - 15 µm

Stable-Labeled Microspheres - 10 µm

Contaminant-Free, BioPAL Sample Vials

Saline-Free Buffer

BioPAL's Microsphere Assay Service







Stable isotope micropsheres is the best way to measure regional blood flow in preclinical research. Florescence microspheres do not have the level of sensitivity compared to BioPAL’s neutron activated microspheres.

BioPAL, Inc. • 80 Webster Street Worcester, MA 01603 • TEL: 508-770-1190 • FAX: 508-770-1191 • e-mail: cs@BioPAL.com

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