The phrase "assay instructions" is correct and usable in written English.
It can be used when referring to guidelines or procedures for conducting an assay, typically in scientific or laboratory contexts.
Example: "Before starting the experiment, please review the assay instructions to ensure accurate results."
Alternatives: "testing guidelines" or "analysis procedures".
Sample preparation, dilution and enzyme detection were performed according to the specific assay instructions.
The genotyping reactions were performed according to the standard Illumina GoldenGate assay instructions (http://www.illumina.com).
All SNP markers were genotyped on a GoldenGate array platform according to the standard Illumina GoldenGate assay instructions (http://www.illumina.com).
PCR cycles were performed according to the assay instructions in an ABI PRISM® 7000 Sequence Detection System (Applied Biosystems).
Urine, serum, and renal IL-6 were measured by ELISA using a species specific (that is, mouse or human) kit according to assay instructions (R&D Systems).
All IGF-I measurements were performed on the iSYS IGF-I immunoassay using the supplied reagents and following the manufacturer's assay instructions [further assay details have been published previously by Bidlingmaier et al. (Bidlingmaier et al., 2014)].
Suspensions of treated and untreated cells were stained according to BacLight assay instruction and 5 µL of each bacterial suspensions were subsequently deposited on slides and analyzed using a fluorescence microscope.
On day 4, media was carefully aspirated and the cells were processed according to the Dual Luciferase Assay kit instructions (Promega # E1910).
After 1 h, the cells were gently rinsed in DPBS, trypsinized, and fixed in 1% formalin for 30 min. Cells were end-labeled per Apo-Brdu TUNEL Assay kit instructions and then analyzed for staining by flow cytometry (BD FACSCalibur).
After 10 days of culture, the control and the zVADfmk/zLLYfmk exposed cells were collected and were subjected to lysis to obtain the cell free cytosolic fraction, as per the assay kit instructions.
Then, the reactions were carried out according to the assay kit instructions.
