The Roles of Sample Pads, Conjugate Pads and Absorbent Pads
A stable rapid test strip depends on coordinated materials. Sample pads, conjugate pads and absorbent pads influence sample conditioning, marker release, flow driving force and reading window.
Sample pads
Sample pads carry the sample, support pretreatment, release buffer components and influence early flow behavior. Different samples such as whole blood, serum, urine and swab extracts require different material choices.
Common development concerns include uneven uptake, unstable flow, treatment chemistry compatibility and nonspecific adsorption. Sample pad treatment often needs to be verified with proteins, surfactants, buffer salts, sugars or other additives.
Conjugate pads / gold conjugate pads
Conjugate pads are closely related to marker release. Colloidal gold, fluorescent beads and latex systems may require different hydrophilicity, release behavior and treatment chemistry.
Gold conjugate pad issues often focus on whether colloidal gold conjugates release quickly, evenly and completely after drying and storage. Ahlstrom 8964, 6613, 8951, 141 and 142 can be discussed for conjugate release scenarios.
Absorbent pads
Absorbent pads provide driving force for flow and influence running time, end-point absorption and reading window stability.
H5072 is one of the absorbent pad directions frequently discussed by customers and should be evaluated with strip length, sample volume, running time and endpoint absorption requirements.
FAQ
Is poor performance always caused by the material itself?
Not always. Treatment buffer, overlap, sample type, humidity, reading time and production process can all influence performance.
Should sample pads be selected by sample type?
Yes. Whole blood, serum, urine, secretions and dairy samples impose different requirements.
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