Antigen Detection

Dumbbell Routines and Exercises

Dumbbell Exercises and Lifting Routines

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Among numerous antigens whose presence and concentration are often assayed by biological sampling, a physiological parameter is chosen as a model illustrating the immunological detection of proteins by LATMAG (Fig. 8). Thyroid-stimulating hormon (TSH) is a major regulating factor of hormone synthesis and secretion, and sensitivity to that parameter is needed for the diagnosis of hyperthyroidism [58].

To demonstrate that several detection methods are compatible with LATMAG, dumbbell suspensions are assayed by spectrophotocolorimetry to measure the turbidity brought by the presence of latex particles (Fig. 9). At very low antigen

Latex Particle Nbr
FIG. 7 Variation of particle number/unit area evaluated from images realized by optical microscopy, as a function of antibody concentration.

FIG. 8 LATMAG protocol for the detection of TSH molecules. Polystyrene latex particles were modified by grafting anti P-TSH antibodies. On the other hand, biotinylated anti a-TSH antibodies were captured onto streptavidin magnetic particles. In the presence of TSH, the formation of dumbbells was evidenced by measuring the optical density or turbidity of the magnetic suspension after the elimination of free latex particles.

FIG. 8 LATMAG protocol for the detection of TSH molecules. Polystyrene latex particles were modified by grafting anti P-TSH antibodies. On the other hand, biotinylated anti a-TSH antibodies were captured onto streptavidin magnetic particles. In the presence of TSH, the formation of dumbbells was evidenced by measuring the optical density or turbidity of the magnetic suspension after the elimination of free latex particles.

FIG. 9 Variation of optical density of dumbbell solution after resuspension as function of TSH concentration in solution.

concentration, the weak absorbance measured is that of magnetic particles, which give an optical density signal even in the absence of specific reaction. This is not observed when detection is carried out with a microscope because magnetic particles are too small to be optically resolved. This background is added to that of false dumbbells, making the method less sensitive although quicker to perform.

For higher TSH concentration, the optical density increases as function of TSH concentration to reach a saturation level where all latex particles are involved in dumbbells and where the supernatant at the issue of magnetic separation is completely clear. Detection limit is estimated at about 6 x 10-8 g/L of TSH, or 2 x 10-12 mol/L which proves that an interesting sensitivity could be achieved with LATMAG even without using a microscope for the detection. A spectrophotometer is used for accurate quantification, but it should be underlined that exactly the same sensitivity is obtained with the naked eye, making this method particulary suitable under conditions in which technical equipment is poor and only a qualitative or semiquantitative assay is needed.

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Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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