Review of pH sensing materials from macro- to nano-scale: Recent developments and examples of seawater applications

Avolio, Roberto; Grozdanov, Anita; Avella, Maurizio; Barton, John; Cocca, Mariacristina; Falco, Francesca De; Dimitrov, Aleksandar; Errico, Maria Emanuela; Fanjul‐Bolado, Pablo; Gentile, Gennaro; Paunović, Perica; Ribotti, Alberto; Magni, Paolo

doi:10.1080/10643389.2020.1843312

Cited by 29 publications

(21 citation statements)

References 154 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The ion-selective membranes transfer the charge to a conductive active layer under varying gate potentials [ 7 ]. Other pH detection methods, including conductometric [ 8 , 9 ] and optical [ 10 , 11 ], operate based on the pH sensitivity of an indicator dye, where adding an organic redox-active indicator is essential. Nevertheless, commercial pH measurements have a number of drawbacks.…”

Section: Introductionmentioning

confidence: 99%

Defect Density-Dependent pH Response of Graphene Derivatives: Towards the Development of pH-Sensitive Graphene Oxide Devices

et al. 2022

View full text Add to dashboard Cite

In this study, we demonstrate that a highly pH-sensitive substrate could be fabricated by controlling the type and defect density of graphene derivatives. Nanomaterials from single-layer graphene resembling a defect-free structure to few-layer graphene and graphene oxide with high defect density were used to demonstrate the pH-sensing mechanisms of graphene. We show the presence of three competing mechanisms of pH sensitivity, including the availability of functional groups, the electrochemical double layer, and the ion trapping that determines the overall pH response. The graphene surface was selectively functionalized with hydroxyl, amine, and carboxyl groups to understand the role and density of the graphene pH-sensitive functional groups. Later, we establish the development of highly pH-sensitive graphene oxide by controlling its defect density. This research opens a new avenue for integrating micro–nano-sized pH sensors based on graphene derivatives into next-generation sensing platforms.

show abstract

Section: Introductionmentioning

confidence: 99%

Defect Density-Dependent pH Response of Graphene Derivatives: Towards the Development of pH-Sensitive Graphene Oxide Devices

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Solid state sensors can provide a cheap, robust and miniaturizable alternative for pH measurements, as Ion Sensitive Field-Effect Transistors (ISFETs) based pH probes. These features can be used to make the sensor system with low power consumption, low cost, and ease of operation [3]. Although ISFETs have small size and fast response time, the need for (glass) reference electrode remains a disadvantage for these sensors.…”

Section: Introductionmentioning

confidence: 99%

“…Applications of EGFET are especially associated with measurement of pH, ionic species, urea and glucose through the functionalization of the gate surface [7]. Popularity of conducting polymers are increasing in the field of sensors due to their low cost, robustness and versatility [3]. Polypyrrole is a conducting polymer that is especially used in potentiometric sensors due to its biocompatibility, high conductivity, easy polymerization, high pH sensitivity and stability [8], [9].…”

Section: Introductionmentioning

confidence: 99%

An Extended Gate Field Effect Transistor (EGFET) pH Microsensor

Avcı

Oğuz

Şen

2021

Preprint

View full text Add to dashboard Cite

Here, an extended – gate field effect transistor (EGFET) pH microsensor was developed for use in fast and sensitive pH measurement applications. The system consisted of two components; a pH sensitive modified gold electrode and a simple and cheap metal oxide semiconductor field-effect transistor (MOSFET). Polypyrrole, a semiconductor and pH responsive polymer, was formed by electropolymerization of pyrrole monomer at the surface of the gold electrode in galvostanic mode. Then, measurements were made in PBS at different pH values using the pH sensitive electrode. In this context, the pH sensitivity of polypyrrole with respect to electropolymerization and incubation time were studied. According to the results, the EGFET pH microsensor formed by 4-min pyrrole electropolymerization showed at pH 6-12 the highest pH sensitivity with 67 mV/pH

show abstract

“…The working principle of ISFET is based on change in current caused by a change in ion concentration. The advantages of ISFET are low power consumption, low cost, ease of operation, small size, fast response time, significant durability, easy storage, and lower temperature dependence (Avolio et al, 2020). In addition, ISFETs are highly sensitive, and can potentially be miniaturized (Ghoneim et al, 2019).…”

Section: Introductionmentioning

confidence: 99%

“…In recent years, popularity of conducting polymers are increasing in the field of sensors due to their low cost, robustness, and versatility (Avolio et al, 2020). Conductive polymers offer a practical matrix, especially for the encapsulation of enzymes in a one-step procedure (Ahuja et al, 2008).…”

Section: Introductionmentioning

confidence: 99%

Detection of pH and Urea with an Extended Gate Field-Effect Transistor Based Microsensor

Avcı¹,

Oğuz²,

Şen³

2021

European Journal of Science and Technology

View full text Add to dashboard Cite

Extended gate field-effect transistor-based (EGFET) microsensors have been developed for highly sensitive detection of pH and urea. EGFET was made by integrating with a microelectrode. Briefly, the EGFET-based pH microsensor was developed by modifying the surface of a microelectrode with polypyrrole (PPy) via electropolymerization and integrating it with a small, simple, and inexpensive metal oxide semiconductor field-effect transistor (MOSFET). As for the EGFET-based urea microsensor, urease enzyme was immobilized in PPy. The measurements of pH and urea were made in solutions at different pH values and the urea concentrations, respectively. The results showed that the pH microsensor had a very good sensitivity of 67 mV/pH in a pH range of 5-12. Similarly, the EGFET-based urea microsensor showed a linear response range of 10 -9 to 10 -5 M urea with sensitivities of 35.5 mV/decade urea and 10 µA/decade urea. The reported EGFET-based pH and urea microsensors have great potential for use in the biomedical field, especially in applications where local analysis is required.

show abstract

Review of pH sensing materials from macro- to nano-scale: Recent developments and examples of seawater applications

Cited by 29 publications

References 154 publications

Defect Density-Dependent pH Response of Graphene Derivatives: Towards the Development of pH-Sensitive Graphene Oxide Devices

Defect Density-Dependent pH Response of Graphene Derivatives: Towards the Development of pH-Sensitive Graphene Oxide Devices

An Extended Gate Field Effect Transistor (EGFET) pH Microsensor

Detection of pH and Urea with an Extended Gate Field-Effect Transistor Based Microsensor

Contact Info

Product

Resources

About