CES conducted the electrical measurement of the devices. All authors read and approved the final manuscript.”
“Background The metal nanoparticles (NPs) are powerful products of nanotechnology, providing broad variety of applications in life science [1, 2]. For example, drug delivery, cellular imaging, and biosensing have been extensively described [3–6]. The chemical versatility of metal NPs holds the potential to outclass in a number of applications [2]. These unique properties and applications of metal NPs are well reviewed [7–9]. Platinum is used in various applications such as catalysts in many organic reactions [10, 11], preparation of organic dyes [12], and biomedical applications [13,

14]. For example, the Pt NPs were employed for successful photothermal treatment of Neuro 2A cancer cell by using irradiation with 1,064 nm near-infrared pulse wave Verteporfin and the Nd YAG laser set at 3 W for 480 s. The Pt NPs increased 9°C in temperature leading to effective Selleck BIBF 1120 photothermal killing of cancer cells [15]. The Pt composite materials have gained much attention due to their good multifunctions [16, 17]. Pt NPs-chitosan composite particles have been extensively studied over the last decade [18, 19], and Pt NPs-chitosan composite bubbles are one of the most emerging and intriguing topics [20, 21]. Bubble particles have import features entrapping air bubbles inside. Due to their low density, bubble particles can float on liquid

surface for specific applications. They can also be applied as novel vehicles for ultrasound-mediated imaging and targeted drug delivery followed by burst release [22–27]. Besides, bubble particles can be utilized as absorbers

to facilitate adsorption of substrates due to a high-surface area. Pt NPs-chitosan composite bubbles can be applied in controlled release and tissue engineering; however, chitosan carrier substrates will disintegrate and dissolve in acid solution such as gastric juices. Therefore, Pt NPs-chitosan composite bubbles are limited in acidic condition. Fortunately, C-X-C chemokine receptor type 7 (CXCR-7) alginate polymer provides a solution to overcome this problem. Alginate polymer has a dense structure to pass the acid solution. To our best knowledge, Pt NPs-alginate composite (Pt NPs@alginate) bubbles are seldom reported in literatures, and they can provide applications for wide pH ranges. By extending our previous works to prepare uniform alginate particles [28–31] and alginate bubbles [32], this work further develops a novel one-step method to fabricate composite Pt NPs@alginate bubbles through a simple chemical reaction. The Pt NPs and bubbles within alginate particles are investigated and characterized. The manufactured alginate products will provide great promise for multifunctional applications. Methods Materials Alginic acid sodium salt (Na-alginate, brown algae with viscosities 150 cp and 350 cp in 2% (w/v) solution at 25°C) and dihydrogen hexachloroplatinate (IV) MLN8237 nmr hexahydrate, ACS, Premion, 99.