[1] [1] PANDEY M，MOHAMAD N，AMIN M C I M. Bacterial cellulose/acrylamide pH-sensitive smart hydrogel: development，characterization，and toxicity studies in ICR mice model[J]. Molecular Pharmaceutics， 2014， 11（10）: 3596-3608.

[2] [2] TARIQ A，BAYDOUN J，REMY C，et al. Fluorescent molecular probe based optical fiber sensor dedicated to pH measurement of concrete[J]. Sensors and Actuators B: Chemical，2021，327: 128906.

[3] [3] WENCEL D，KAWOREK A，ABEL T，et al. Optical sensor for real-time pH monitoring in human tissue[J].Small，2018，14（51）: 1803627.

[5] [5] ALHAYALI S K，SALMAN A M，ALJANABI A H.Low-cost high-sensitivity pH sensor based on a droplet-shaped single-mode fiber Mach-Zehnder interferometer[J]. Optical Fiber Technology，2022，71: 102944.

[6] [6] FRANKER C G，HUSSIAN K J，DORGE T C，et al. Optical chemical sensor using intensity ratiometric fluorescence signals for fast and reliable pH determination[J].ACS Sensors，2018，4（1）: 26-31.

[7] [7] ZHAO L，LI G，GAN J，et al. Hydrogel optical fiber based ratiometric fluorescence sensor for highly sensitive pH detection[J]. Journal of Lightwave Technology，2021，39（20）: 6653-6659.

[8] [8] LIU T，WANG W，DING H，et al. Smartphone-based hand-held optical fiber fluorescence sensor for on-site pH detection[J]. IEEE Sensors Journal，2019，19（20）:9441-9446.

[9] [9] ZHANG Y，DING L，ZHANG H，et al. A new optical fiber biosensor for acetylcholine detection based on pH sensitive fluorescent carbon quantum dots[J]. Sensors and Actuators B: Chemical，2022，369: 132268.

[10] [10] ZHAO Y，LEI M，LIU S X，et al. Smart hydrogel-based optical fiber SPR sensor for pH measurements[J]. Sensors and Actuators B: Chemical，2018，261: 226-232.

[11] [11] YAN R，SANG G，YIN B，et al. Temperature self-calibrated pH sensor based on GO/PVA-coated MZI cascading FBG[J]. Optics Express，2021，29（9）: 13530-13541.

[12] [12] LEI Y，GONG Z，LI Y，et al. Highly sensitive physiological sensor based on tapered fiber-optic interferometer for sweat pH detection[J]. IEEE Sensors Journal，2023（6）：1558-1748.

[13] [13] PABBISETTI V N K，MADHUVARASU S S. Hydrogel-coated fiber Bragg grating sensor for pH monitoring[J]. Optical Engineering，2016，55（6）: 066112-066112.

[14] [14] JANTING J，PEDERSEN J K M，WOYESSA G，et al.Small and robust all-polymer fiber Bragg grating based pH sensor[J]. Journal of Lightwave Technology，2019，37（18）:4480-4486.

[15] [15] LIU Y，LIU B，FENG X，et al. High-birefringence fiber loop mirrors and their applications as sensors[J]. Applied Optics，2005，44（12）: 2382-2390.

[17] [17] PATHAK A K，SINGH V K. A wide range and highly sensitive optical fiber pH sensor using polyacrylamide hydrogel[J]. Optical Fiber Technology，2017，39: 43-48.

[18] [18] NESRINNE S，DJAMEL A. Synthesis，characterization and rheological behavior of pH sensitive poly （acrylamide-co-acrylic acid）hydrogels[J]. Arabian Journal of Chemistry，2017，10（4）: 539-547.

[19] [19] LONG G，WAN L，XIA B，et al. Rapid-response and wide-range pH sensors enabled by self-assembled functional PAni/PAA layer on no-core fiber[J]. Materials，2022，15（21）: 7449.

[20] [20] LU Q，LIU Z，ZHANG H，et al. Optical pH sensor based on fiber interferometer coated with intelligent hydrogel[C]//Advanced Sensor Systems and Applications XIII，Beijing，China: SPIE，2023，12771: 56-62