title: Micromotors Spontaneously Neutralize Gastric Acid for pH-Responsive Payload Release.
abstract: The highly acidic gastric environment creates a physiological barrier for using therapeutic drugs in the stomach. While proton pump inhibitors have been widely used for blocking acid-producing enzymes, this approach can cause various adverse effects. Reported herein is a new microdevice, consisting of magnesium-based micromotors which can autonomously and temporally neutralize gastric acid through efficient chemical propulsion in the gastric fluid by rapidly depleting the localized protons. Coating these micromotors with a cargo-containing pH-responsive polymer layer leads to autonomous release of the encapsulated payload upon gastric-acid neutralization by the motors. Testing in a mouse model demonstrate that these motors can safely and rapidly neutralize gastric acid and simultaneously release payload without causing noticeable acute toxicity or affecting the stomach function, and the normal stomach pH is restored within 24 h post motor administration.
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Jinxing
authors.initials: J
authors.lastname: Li
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Pavimol
authors.initials: P
authors.lastname: Angsantikul
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Liu
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Berta
authors.initials: B
authors.lastname: Esteban-Fernández de Ávila
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Soracha
authors.initials: S
authors.lastname: Thamphiwatana
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Mingli
authors.initials: M
authors.lastname: Xu
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Elodie
authors.initials: E
authors.lastname: Sandraz
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Wang
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Jorge
authors.initials: J
authors.lastname: Delezuk
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Gao
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Liangfang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Wang
mesh_terms: D000818:Animals; D003692:Delayed-Action Preparations / Q000737:chemistry*; D065546:Drug Liberation; D005456:Fluorescent Dyes / Q000008:administration & dosage; D005744:Gastric Acid / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry*; D051379:Mice; D011108:Polymers / Q000737:chemistry*; D011109:Polymethacrylic Acids / Q000737:chemistry; D012235:Rhodamines / Q000008:administration & dosage
chemical_list: D003692:Delayed-Action Preparations; D005456:Fluorescent Dyes; D011108:Polymers; D011109:Polymethacrylic Acids; D012235:Rhodamines; C038300:methylmethacrylate-methacrylic acid copolymer; D006046:Gold; D008274:Magnesium
keywords: drug delivery; gastric acid; micromotor; proton pump inhibitor; responsive release