Cellulose fiber

Example 2

FIG. 7 shows a non-limiting example of an interior of a reflux device, which is included in embodiments of the present invention. Samples flow from A to B. Test strips for lateral flow assay are composed of (in this order): a sample pad (VF2; Whatman); a second pad (ReliaFlow, Ahlstrom); a membrane (UniSart CN 95, Sartorius); an absorbent pad (Cellulose fiber, Millipore). 1, 100 μl 0.9% NaCl dispensed upstream from the blood sample, at position A; 2, 100 μl of buffer (10 mM phosphate buffer pH 7.4, plus 137 mM NaCl, plus 0.02% triton-X-100) was dispensed immediately downstream from the blood sample in an angle and contrary to the direction of sample flow; 3, 100 μl of 0.9% NaCl was dispensed immediately downstream from the blood sample in an angle, and contrary to the direction of sample flow. Although the sample pad is composed of a bibulous material design to retain blood cells, the flow in (1) causes red blood cells to move into the membrane when liquid is applied above or upstream the sample. Dispensing of the liquid in (2) and (3) created a reflux compelling cells to the edge (position A) prior to resuming liquid flow towards the membrane. The leakage is more accentuated as the blood volume increases.

Example 4

FIG. 10 shows a non-limiting example of an interior of a device, which is included in embodiments of the present invention. Samples flow from A to B. Test strips for lateral flow assay are composed of (in this order): a sample pad (LF1, GE Healthcare); a second pad (ReliaFlow, Ahlstrom) containing latex-labeled goat anti-human IgG; a membrane (Hi-Flow HF075, Millipore) where both a control antibody (rabbit anti-goat IgG, Thermo Fisher) and a chimeric antibody (chimeric-adalimumab) were immobilized, the latter being composed of the adalimumab variable region fused with mouse IgG2a constant region (Anti-hTNF-α-mlg2a, InvivoGen); an absorbent pad (cellulose fiber, Millipore). 1, no anti-adalimumab antibody in the buffer sample (10 mM phosphate buffer pH 7.4, plus 137 mM NaCl, plus 0.02% triton-X-100); 2, 5 μl of sheep blood; 3, 1 μl of anti-adalimumab antibody (HCA204, 500 m/ml, AbD Serotec) spiked on 5 μl of sheep blood; 4, 1 μl of anti-adalimumab antibody (HCA204, 500 m/ml, AbD Serotec) spiked on 5 μl of sheep blood. Following sample application, 50 μl of buffer (10 mM phosphate buffer pH 7.4, plus 137 mM NaCl, plus 0.02% triton-X-100) was added downstream of the sample application in an angle, and contrary to the direction of sample flow, to create a reflux. Sheep blood was obtained from Rockland Inc. (Limerick, Pa.).

Example 3

FIG. 8 shows a non-restrictive example of an interior of a reflux device, which is included in embodiments of the present invention. Samples flow from A to B. The test strips for lateral flow were composed of (in this order): a sample pad (CytoSep HV, Ahlstrom); a second pad (ReliaFlow, Ahlstrom); a membrane (HF075, Millipore); an absorbent pad (cellulose fiber, Millipore). Tests were performed with sheep blood obtained from Rockland Inc. (Limerick, Pa.); blood volumes of 5 μl, 10 μl, 15 μl, and 20 μl were dispensed at the end of the sample pad (position A), followed by 60 μl of buffer (10 mM phosphate buffer pH 7.4, plus 137 mM NaCl, plus 0.02% triton-X-100), said buffer dispensed in an angle and contrary to the direction of sample flow, to create a reflux. The corresponding drops of blood are shown to the right of the figure.