DESCRIPTION

Syntaxins are a family of transmembrane proteins that belong to the SNARE complex. In conjunction with other SNAREs and with the cytoplasmic NSF and SNAP proteins, syntaxins mediate vesicle fusion in diverse vesicular transport processes along the exocytic and endocytic pathways. Syntaxin 1A (STX1A) and 1B (STX1B), two closely related isoforms of syntaxin 1, are involved in synaptic vesicle docking and fusion during neurotransmitter release. Syntaxin 1A is associated with a variety of neurological diseases, including epilepsy, attention deficit hyperactivity disorder (ADHD), and migraine.

PRINCIPLE OF THE ASSAY

Sandwich ELISA structure (Detection antibody labeled with HRP) A capture antibody is pre-coated onto the bottom of wells which binds to analyte of interest. A detection antibody labeled with HRP also binds to the analyte. TMB acts as the HRP substrate and the solution color will change from colorless to blue. A stop solution containing sulfuric acid turns solution yellow. The color intensity is proportional to the quantity of bound protein which is measurable at 450 nm with the correction wavelength set at 630 nm.

PRECISION

Intra-assay Precision (Precision within an assay) Three samples of known concentration were tested 20 times on one plate to assess intra-assay precision. Inter-assay Precision (Precision between assays) Three samples of known concentration were tested in 24 separate assays to assess inter-assay precision.

Intra-assay Precision

Sample	n	Mean (pg/mL)	SD	CV%
1	20	266.2	5.3	2.0
2	20	66.5	2.4	3.6
3	20	18.0	0.8	4.5

Inter-assay Precision

Sample	n	Mean (pg/mL)	SD	CV%
1	24	272.6	14.6	5.4
2	24	70.8	5.4	7.6
3	24	18.3	1.1	5.8

RECOVERY

The recovery of human/rat STX1A spiked to three different levels throughout the range of the assay in tissue lysate was evaluated.

Sample Type		Average% of Expected	Range (%)
Tissue lysate	1:16	103	93-114
	1:32	99	79-115

LINEARITY

To assess the linearity of the assay, samples were diluted with the appropriate Sample Diluent to produce samples with values within the dynamic range of the assay. (The tissue lysate was initially diluted 1:2.)

		Tissue lysate
1:2	Average% of Expected	100
	Range (%)	-
1:4	Average% of Expected	76
	Range (%)	74-77
1:8	Average% of Expected	97
	Range (%)	88-106
1:16	Average% of Expected	112
	Range (%)	98-125

CALIBRATION

This immunoassay is calibrated against a highly purified recombinant human Human/Rat STX1A Sandwich ELISA Kit produced at Sunlong Medical™.