title: Development of chitosan/β-glycerophosphate/glycerol hydrogel as a thermosensitive coupling agent.
abstract: This work develops a dual-function thermosensitive hydrogel to prevent overheating, a side effect of focused ultrasound therapy. The proposed hydrogel has the components of chitosan, β-glycerophosphate, and glycerol. Its thermosensitive sol-to-gel transition gives an instant signal of overheating without the need of any awkward sensing device. Impacts of varying component concentrations on the sol-to-gel temperature, rate, and degree of transparency are also investigated. Chemical structures and ultrasonic coefficients after heating are obtained with a Fourier transform infrared spectroscopy and ultrasonic measurement, respectively. Optimized formula of the proposed hydrogel is 0.5% chitosan, 5% β-glycerophosphate, and 25% glycerol. This hydrogel has a high acoustic impedance (Z=1.8 Mrayl) close to that of human skin, high ultrasonic transmission (T=99%, which is normalized to water) from 25 to 55°C, and low attenuation coefficient (α=4.0Np/m). These properties assure the success of dual functions of the hydrogel developed in this work.
authors.affiliation: Department of Mechanical Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan; Center for Fundamental Science, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
authors.forename: Chih-Ling
authors.initials: CL
authors.lastname: Huang
authors.affiliation: Department of Mechanical Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan. Electronic address: ybchen@mail.ncku.edu.tw.
authors.forename: Yu-Bin
authors.initials: YB
authors.lastname: Chen
authors.affiliation: Department of Mechanical Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan; Advanced Optoelectronic Technology Center, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan.
authors.forename: Yu-Lung
authors.initials: YL
authors.lastname: Lo
authors.affiliation: Department of Mechanical Engineering, National Cheng Kung University, No. 1, University Road, Tainan 701, Taiwan.
authors.forename: Yi-Hsiang
authors.initials: YH
authors.lastname: Lin
mesh_terms: D048271:Chitosan / Q000737:chemistry*; D005990:Glycerol / Q000737:chemistry*; D005994:Glycerophosphates / Q000737:chemistry*; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D020100:Hydrogels / Q000737:chemistry*; D013696:Temperature; D014464:Ultrasonic Therapy / Q000295:instrumentation*
chemical_list: D005994:Glycerophosphates; D020100:Hydrogels; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D048271:Chitosan; D005990:Glycerol; C031463:beta-glycerophosphoric acid
keywords: Acetic acid (PubChem CID: 176); Chitosan; Chitosan (PubChem CID: 71853); Coupling agent; Glycerol; Glycerol (PubChem CID: 753); Thermosensitive hydrogel; Ultrasonic; β-glycerophosphate; β-glycerophosphate (PubChem CID: 6101544)