Antitussive and expectorant viscosity

Use

To relieve cough and chest congestion.

METHOD 1

Test equipment

Instrument: Viscometer or rheometer

Torque range: RV

Pin: YULA-15E

Accessories: Enhanced UL Adapter,

TC-550AP

Programmable wash speed: 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160 and 170 rpm

Temperature: 22 ° C

Test method

We used a Brookfield RVDV3T rheometer with Rheocalc ™ software for automated instrument control and data acquisition. The temperature was controlled using a ULA-EY water jacket connected to a TC-550AP refrigerated programmable bath. We conducted three trials to determine repeatability. A syringe was used to measure and dispense 16 ml of the substance into the sample chamber. The spindle and chamber were cleaned before each test, and fresh material was used in each test. We equilibrated the sample, spindle, and chamber for at least three minutes prior to testing. We performed our test in speed ramp mode. Using traditional RV speeds such as 50 and 100 RPM may be a sufficient test for this type of material. However, since we were using a DV3T rheometer, we had the flexibility to run the test at a wide variety of speeds.

Figure 1 shows that Mark A and Mark B are essentially Newtonian fluids. Newtonian fluids are characterized by a constant viscosity, independent of the shear rate. Slight differences in viscosity over our shear rate range can be explained by the tolerance of 1% of the instrument. Figure 1 also shows that brand A is more viscous than brand B.

Figure 1: Viscosity versus shear rate

METHOD 2

Test equipment

Instrument: DV3T / DVnext rheometer

Torque range:

LV pin: YULA-15E

Accessories: Enhanced UL Adapter, TC-550AP Programmable Bath

Speed: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 and 15 rpm

Temperature: 22 ° C

Test method

We used a Brookfield LVDV3T rheometer with Rheocalc ™ software for automated instrument control and data acquisition. The temperature was regulated using a ULA-EY water jacket connected to a TC-550AP programmable bath. We conducted three trials to determine repeatability. A syringe was used to measure and dispense 16 ml of the substance into the sample chamber. The spindle and chamber were cleaned before each test, and fresh material was used in each test. We equilibrated the sample, spindle, and chamber for at least three minutes prior to testing. We performed our test in speed ramp mode. Using traditional LV speeds such as 3, 6 and 12 RPM may be a sufficient test for this type of material. However, since we were using a DV3T rheometer, we had the flexibility to run the test at a wide variety of speeds.

Figure 2 shows that Mark A and Mark B are essentially Newtonian fluids. Newtonian fluids are characterized by a constant viscosity, independent of the shear rate. Slight differences in viscosity over our shear rate range can be explained by the tolerance of 1% of the instrument. Figure 2 also shows that brand A is more viscous than brand B.

Figure 2: viscosity vs rotational speed