Optical fiber sensors predicated on waveguide technology are promising and attractive in chemical, biotechnological, agronomy, and civil engineering applications. of 1 1,550 nm. Experimental results show that the sensitivity of the LPFG sensor by light intensity interrogation was determined to be 5.0 10?6 mW/mg/L for chloride ion concentrations below 2,400 mg/L. The results obtained from the analysis of data variations in time-series measurements for Laniquidar all sample materials show that standard deviations of output power were relatively small and found in the range of 7.413 10?5?2.769 10?3 mW. In addition, a fairly small coefficients of variations were also obtained, which were in the range of 0.03%C1.29% and decreased with the decrease of chloride ion concentrations of sample materials. Moreover, the analysis of stability performance of the LPFG sensor indicated that the random walk coefficient Bmp8b decreased with the increase of the chloride ion concentration, illustrating that measurement stability using the microfluidic platform was capable of measuring transmitted optical power with accuracy in the range of ?0.8569 mW/ to ?0.5169 mW/ density at 20 C [24]. The realization of a liquid tunable long-period grating using multiphase droplet microfluidics that is integrated onto a microfluidic chip to test de-ionized (DI) water and CaCl2 solutions using a 1,550 nm light source is reported in [25]. This study addresses the development of an LPFG-based microfluidic chip for chloride ion measurement using different kinds of water and chloride ion concentration solutions. The use Laniquidar of hybrid microfluidic potato chips and LPFG detectors are proven to have advantages of sensing really small quantities of examples, detections with high level of sensitivity and quality, low cost, brief moments for data acquisition and sent optical power analysisonly, and basic experimental setup products for different test components with or Laniquidar without chloride ion focus. Furthermore, the mix of a multi-D-shaped optical dietary fiber and a microfluidic chip offers successfully proven the feasibility of fabricating a course of high delicate refractive-index sensor only using light intensitytransmitted optical power [26]. With this structure, only a laser beam diode source connected with an optical power meter is necessary for sign interrogation. Costly and high accuracy apparatus like a broadband amplified spontaneous emission (ASE) dietary fiber source connected with a high-resolution optical range analyzer (OSA) isn’t necessary. Thus, advantages from the microfluidic system are simpleness, compactness, low priced, small quantity, high integration, and period savings for tests. With this paper, we centered on the usage of LPFG-based microfluidic chip as chloride ion focus sensor as well as the light strength from the LPFG in the output power was used to quantify the Laniquidar chloride ion concentrations of different kinds of waters, aqueous samples of sea sand soaked in RO water, and seawater. The wavelength shift information was not used to quantify the chloride-ion concentration or the refractive index of sample materials. Additionally, a chloride ion-selective electrode (ISE) sensor (CL-BTA, Vernier) was employed and calibrated with high (1,000 mg/L) and low (10 mg/L) standard solutions. The chloride ISE has a resolution about 0.7% of reading (1.8 0.013 or 35,500 250 mg/L) and was used to measure chloride-ion concentrations in various samples with sea sand or seawater. Results from these two sensors show a useful correlation (R2 = 0.975) between the ISE-measured chloride concentration and LPFG-measured transmitted light intensity at a wavelength of 1 1,550 nm ( 10?4, periods between 100 m?1 mm and length of 2C4 cm. The LPFG couples light from a guided fundamental core mode (LPand are propagating constants of the fundamental core mode and in the transmission spectrum. The center wavelengths of an attenuation band are solutions of the following equation [23]: is.