▎ 摘　　要

NOVELTY - Preparing S-shaped optical fiber cone immune sensor, comprises (a) taking a section of 30-60 cm long optical fiber, then stripping middle 2-4 cm coating layer by optical fiber clamp, using alcohol cotton to wipe clean, placing pre-processed optical fiber in groove, fixing by optical fiber clamps, setting the discharging time and current of fusion splicer puller, (b) performing biological functionalization of fiber cone by soaking in phosphate buffer salt solution containing 0.1-3 mg/ml nano-antibody, heating, using graphene oxide ethanol solution to soak, soaking in colloidal gold solution, and (c) soaking graphene oxide/gold nano-particle functionalized S-shaped optical fiber cone into 11-mercaptoundecanoic acid-ethanol solution, incubating, soaking in 2-(N-morpholino)ethanesulfonic acid buffer solution of 1-(3-dimethylaminopropyl)- 3-ethylcarbodiimide, soaking in phosphate buffer solution, incubating, then using phosphate buffer salt solution to wash and remove unbound protein. USE - The optical fiber cone immune sensor is useful in detection (claimed). ADVANTAGE - The immune sensor: has high affinity, specific strong nano-antibody to achieve the specific recognition and binding of carcinoembryonic antigen and fast detection without labeling, thus improving the antigen detection specificity, stability and sensitivity; and has simple, short and economical preparation process. DETAILED DESCRIPTION - Preparing S-shaped optical fiber cone immune sensor, comprises (a) taking a section of 30-60 cm long optical fiber, then stripping the middle 2-4 cm coating layer by optical fiber clamp, using alcohol cotton to wipe clean the part of the optical fiber with the coating layer removed along the same direction of the optical fiber axis to complete the optical fiber pretreatment, adjusting the optical fiber clamp at the fusion splicer two ends, ensuring the axial staggered distance is 100-250 mu m, then flatly placing the pre-processed optical fiber in a groove of the fusion splicer, adjusting the placing position of the optical fiber and the discharge electrode of the fusion splicer opposite to the middle part of the coating layer-stripped optical fiber, fixing by optical fiber clamps at two ends, setting the discharging time and discharging current of the welding machine pulling cone in two stages, where the discharge time of the first stage is 7-15 ms and discharge current is 8-16 mA, the discharge time of the second stage is 6-12ms and the discharge current is 6-10 mA, finally pressing the Fuse key on the fusion splicer, (b) performing biological functionalization of the S-shaped optical fiber cone by soaking the S-shaped optical fiber cone in acetone for 10-60 minutes, and then soaking in sodium hydroxide aqueous solution with concentration of 0.5-2 M for 1-4 hours, then soaking 3-aminopropyl triethoxy silane-aqueous solution of 1-10% volume concentration for 1-6 hours, cleaning, heating for 5-20 minutes at 50-150 degrees C, then using graphene oxide ethanol solution to soak for 1-6 hours, then soaking with 3-mercaptopropyl triethoxy silane-benzene solution with volume concentration of 0.01-1% for 2-10 hours, and then soaking in colloidal gold solution for 5-30 hours, and (c) soaking the graphene oxide/gold nano-particle functionalized S-shaped optical fiber cone into 11-mercaptoundecanoic acid-ethanol solution of 10-40 mM concentration, incubating for 10-60 minutes, soaking in 2-(N-morpholino)ethanesulfonic acid buffer solution of 1-(3-dimethylaminopropyl)- 3-ethylcarbodiimide of 10-40 mM concentration for 19-50 minutes, soaking in phosphate buffer solution of N-hydroxysuccinimide of 30-90 mM concentration for 10-50 minutes, soaking in phosphate buffer salt solution containing 0.1-3 mg/ml nano-antibody for 10-60 minutes, then soaking in 0.2-2 mg/ml bovine serum albumin solution, incubating for 0.5-2 hours, then using phosphate buffer salt solution to wash and remove the unbound protein. An INDEPENDENT CLAIM is also included for the S-shaped optical fiber cone immune sensor, prepared by the method.