Xiaojiang is a past Ph.D. student of the Bakker group who joined us from Nanjing University in China. He came as a Masters student to Geneva and became very quickly extraordinarily productive and completed his doctoral work in record time. His synthetic, conceptual, experimental and writing skills allowed him to work on a very wide range of topics.
After his Ph.D. he went for a postdoc to the laboratory of Ludovic Jullien at ENS in Paris. He is currently an Associate Professor of Analytical Chemistry as SusTech in Shenzhen, China. Linkedin.

Thesis title: From Ion Selective Optodes to Photoelectric Conversion (2015). DOI Link

Publications:

(1)   Direct Potentiometric Sensing of Anion Concentration (Not Activity), Gao, W.; Xie, X.; Bakker, E. ACS Sensors, 2020, 5, 313-318. DOI: 10.1021/acssensors.9b02523 (open access).

(2)   A Solid-State Reference Electrode Based on a Self-Referencing Pulstrode, Gao, W.; Zdrachek, E.; Xie, X.; Bakker, E. Angew. Chem. Int. Ed., 2020, 59, 2294-2298. DOI: 10.1002/anie.201912651.

(3)   Electrogenerated Chemiluminescence for Chronopotentiometric Sensors, Gao, W.; Jeanneret, S.; Yuan, D.; Cherubini, T.; Wang, L.; Xie, X.; Bakker, E. Anal. Chem., 2019, 91, 4889–4895. DOI: 10.1021/acs.analchem.9b00787 (open access).

(4)   Simplified Fabrication for Ion-Selective Optical Emulsion Sensor with Hydrophobic Solvatochromic Dye Transducer: A Cautionary Tale, Wang, L.; Sadler, S.; Cao, T.; Xie, X.; Bakker, E. Anal. Chem., 2019, 91, 8973-8978. DOI: 10.1021/acs.analchem.9b01145 (open access).

(5)   Surface modified polystyrene microsensors containing lipophilic solvatochromic dye transducers, Wang, L.; Xie, X.; Cao, T.; Szilagyi, I.; Bakker, E. Chem. Eur. J., 2018, 24, 7921-7925. DOI: 10.1002/chem.201800077.

(6)   Agarose Hydrogel Containing Immobilized pH Buffer Microemulsion without Increasing Permselectivity, Coll Crespi, M.; Crespo, G. A.; Xie, X.; Touilloux, R.; Tercier-Waeber, M. L.; Bakker, E. Talanta, 2018, 177, 191-196. DOI: 10.1016/j.talanta.2017.08.053.

(7)   Ionophore-Based Titrimetric Detection of Alkali Metal Ions in Serum, Zhai, J.; Xie, X.; Cherubini, T.; Bakker, E. ACS Sensors, 2017, 2, 606–612. DOI: 10.1021/acssensors.7b00165 (open access).

(8)   Reversible pH-independent optical potassium sensor with lipophilic solvatochromic dye transducer on surface modified microporous nylon, Wang, L.; Xie, X.; Zhai, Z.; Bakker, E. Chem. Commun., 2016, 52, 14254 - 14257. DOI: 10.1039/C6CC07841A.

(9)   Determination of pKa Values of Hydrophobic pH Sensitive Colorimetric Probes in Nanospheres, Xie, X.; Zhai, J.; Jarolimova, Z.; Bakker, E. Anal. Chem., 2016, 88, 3015–3018. DOI: 10.1021/acs.analchem.5b04671.

(10)   Ion-Selective Optical Nanosensors based on Solvatochromic Dyes with Different Lipophilicity: From Bulk Partitioning to Interfacial Accumulation, Xie, X.; Szilagyi, I.; Zhai, J.; Wang, L.; Bakker, E. ACS Sensors, 2016, 1, 516–520. DOI: 10.1021/acssensors.6b00006 (open access).

(11)   Solvatochromic dyes as pH independent indicators for ionophore emulsion based complexometric titrations, Zhai, J.; Xie, X.; Bakker, E. Anal. Chem., 2015, 87, 11587-11591. DOI: 10.1021/acs.analchem.5b03526.

(12)   Determination of Effective Stability Constants of Ion-Carrier Complexes in Ion Selective Nanospheres with Charged Solvatochromic Dyes , Xie, X.; Bakker, E. Anal. Chem., 2015, 87, 11587–11591. DOI: 10.1021/acs.analchem.5b03526.

(13)   Charged Solvatochromic Dyes as Signal Transducers in pH Independent Fluorescent and Colorimetric Ion Selective Nanosensors, Xie, X.; Gutierrez, A.; Trofimov, V.; Szilagyi, I.; Soldati, T.; Bakker, E. Anal. Chem., 2015, 87, 9954–9959. DOI: 10.1021/acs.analchem.5b02566.

(14)   Anion-Exchange Nanospheres as Titration Reagents for Anionic Analytes , Zhai, J.; Xie, X.; Bakker, E. Anal. Chem., 2015, 87, 8347–8352. DOI: 10.1021/acs.analchem.5b01530.

(15)   Potassium Sensitive Optical Nanosensors Containing Voltage Sensitive Dyes, Xie, X.; Gutierrez, A.; Trofimov, V.; Szilágyi, I.; Soldati, T.; Bakker, E. Chimia, 2015, 69, 196-198. DOI: 10.2533/chimia.2015.196 (open access).

(16)   Ion-Selective Optode Nanospheres as Heterogeneous Indicator Reagents in Complexometric Titrations, Zhai, J.; Xie, X.; Bakker, E. Anal. Chem., 2015, 87, 2827–2831. DOI: 10.1021/ac504213q.

(17)   Ion Selective Optodes: From the Bulk to the Nanoscale, Xie, X.; Zhai, J.; Bakker, E. Anal. Bioanal. Chem., 2015, 407, 3899-3910. DOI: 10.1007/s00216-014-8413-4.

(18)   Advancing Schwarzenbach’s complexometry: nanoscale titration reagents based on heterogeneous reactions, Zhai, J.; Xie, X.; Bakker, E. Chimia, 2014, 68, 899. DOI: 10.2533/chimia.2014.899 (open access).

(19)   Detecting and Manipulating Ions: From Potentiometry to the Nanoscale, Xie, X.; Bakker, E. q&more, 2014, 2, 6-11. DOI: http://q-more.chemeurope.com/q-more-articles/173/detecting-and-manipulating-ions.html (open access).

(20)   Potentiometric Response from Ion-Selective Nanospheres with Voltage-Sensitive Dyes, Xie, X.; Zhai, J.; Bakker, E. J. Am. Chem. Soc., 2014, 136, 16465-16468. DOI: 10.1021/ja5107578 (open access).

(21)   Ionophore-based ion-exchange emulsions as novel class of complexometric titration reagents, Zhai, J.; Xie, X.; Bakker, E. Chem. Commun., 2014, 50, 12659 - 12661. DOI: 10.1039/c4cc05754f.

(22)   Bringing Ion-Selective Sensors to the Nanoscale: Blurring the Lines Between Sensing and Bulk Solution Chemistry, Xie, X.; Bakker, E. Anal. Scientist, 2014, 20, 17-18. DOI: https://theanalyticalscientist.com/issues/0914/shrinking-ion-selective-sensors-for-success/ (open access).

(23)   Visible Light Induced Photoacid Generation within Plasticized PVC Membranes for Copper (II) Ion Extraction, Xie, X.; Mistlberger, G.; Bakker, E. Sens. Actuators, B, 2014, 204, 807–810. DOI: 10.1016/j.snb.2014.08.041.

(24)   Creating electrochemical gradients by light: from bio-inspired concepts to photoelectric conversion, Xie, X.; Bakker, E. PhysChemChemPhys, 2014, 16, 19781 - 19789. DOI: 10.1039/c4cp02566k.

(25)   Ionophore based Ion-Selective Optical NanoSensors Operating in Exhaustive Sensing Mode, Xie, X.; Zhai, J.; Crespo, G. A.; Bakker, E. Anal. Chem., 2014, 86, 8770–8775. DOI: 10.1021/ac5019606 (open access).

(26)   Direct Alkalinity Detection with Ion-Selective Chronopotentiometry, Ghahraman Afshar, M.; Crespo, G. A.; Xie, X.; Bakker, E. Anal. Chem., 2014, 86, 6461–6470. DOI: 10.1021/ac500968c (open access).

(27)   Photoelectric Conversion based on Proton-Coupled Electron Transfer Reactions, Xie, X.; Bakker, E. J. Am. Chem. Soc., 2014, 136, 7857–7860. DOI: 10.1021/ja503491k (open access).

(28)   Potassium-Selective Optical Microsensors Based On Surface Modified Polystyrene Microspheres, Xie, X.; Crespo, G. A.; Zhai, J.; Szilagyi, I.; Bakker, E. Chem. Commun., 2014, 50, 4592-4595. DOI: 10.1039/C4CC01313A.

(29)   Chronopotentiometric Carbonate Detection with All-Solid-State Ionophore-Based Electrodes, Jarolimova, Z.; Crespo, G. A.; Xie, X.; Ghahraman Afshar, M.; Pawlak, M.; Bakker, E. Anal. Chem., 2014, 86, 6307–6314. DOI: 10.1021/ac5004163.

(30)   pH Independent Nano-Optodes Based on Exhaustive Ion-Selective Nanospheres, Xie, X.; Zhai, J.; Bakker, E. Anal. Chem., 2014, 86, 2853–2856. DOI: 10.1021/ac403996s.

(31)   Light Controlled Reversible Release and Uptake of Potassium Ions from Ion-Exchanging Nanospheres, Xie, X.; Bakker, E. ACS App. Mater. Inter., 2014, 6, 2666–2670. DOI: 10.1021/am4049805.

(32)   Photocurrent Generation Based on Light-Driven Proton Pump in Supported Liquid Membranes Doped with Photoswitchable Spiropyran , Xie, X.; Crespo, G. A.; Mistlberger, G.; Bakker, E. Nature Chem., 2014, 6, 202-207. DOI: 10.1038/nchem.1858.

(33)   Ultrasmall Fluorescent Ion-Exchanging Nanospheres Containing Selective Ionophores, Xie, X.; Mistlberger, G.; Bakker, E. Anal. Chem., 2013, 85, 9932–9938. DOI: 10.1021/ac402564m (open access).

(34)   Oxazinoindolines as Fluorescent H+ Turn-On Chromoionophores For Optical and Electrochemical Ion Sensors, Xie, X.; Crespo, G. A.; Bakker, E. Anal. Chem., 2013, 85, 7434–7440. DOI: 10.1021/ac401367b (open access).

(35)   Photoresponsive Ion Extraction/Release Systems: Dynamic Ion Optodes for Calcium and Sodium Based on Photochromic Spiropyran, Mistlberger, G.; Xie, X.; Pawlak, M.; Crespo, G.; Bakker, E. Anal. Chem., 2013, 85, 2983-2990. DOI: 10.1021/ac4000283.

(36)   A Non-Severinghaus Potentiometric CO2 Sensor with Improved Characteristics, Xie, X.; Bakker, E. Anal. Chem., 2013, 85, 1332-1336. DOI: 10.1021/ac303534v (open access).

(37)   Reversible Photodynamic Chloride-Selective Sensor Based on Photochromic Spiropyran, Xie, X.; Mistlberger, G.; Bakker, E. J. Am. Chem. Soc., 2012, 134, 16929–16932. DOI: 10.1021/ja307037z.

(38)   Photodynamic ion sensor systems with spiropyran: photoactivated acidity changes in plasticized poly(vinyl chloride), Mistlberger, G.; Crespo, G.A.; Xie, X.; Bakker, E. Chem. Commun., 2012, 48, 5662-5664. DOI: 10.1039/C2CC30657C.

(39)   Direct Optical Carbon Dioxide Sensing Based on a Polymeric Sensing Film Doped with a Selective Molecular Tweezer Type Ionophore, Xie, X.; Tercier-Waeber, M.; Pawlak, M.; Bakker, E. Anal. Chem., 2012, 84, 3163-3169. DOI: 10.1021/ac2030046 (open access).

(40)   Advancing Membrane Electrodes and Optical Ion Sensors, Bakker, E.; Crespo, G.; Grygolowicz-Pawlak, E.; Mistlberger, G.; Pawlak, M.; Xie, X. Chimia, 2011, 65, 141-149. DOI: 10.2533/chimia.2011.141.