*Paper-Based Biosensors for Analysis of Water DOI: http://dx.doi.org/10.5772/intechopen.84131*

*Biosensors for Environmental Monitoring*

**88**

**Target** Pharmaceuticals

Ethinylestradiol (EE2)

EE2 Antibiotics inhibiting

protein synthesisa

Metals

Arsenic, mercury

Lead ion Uranium (VI)

Arsenite

Cd2+ Pathogens

*E. coli* and Zika virus

E. coli K12 and Zika

virus

Bacterial cultures from

Synthetic

Cotton-based paper; screen printing

E

Lectin concanavalin A

1.9 × 103 CFU mL−1

[27]

wastewater

sewage sludge

Deionized water;

Paper Chr. grade 2; wax printing

P

Antibody-conjugated

1 log CFU mL−1

20 pg mL−1 c

 b;

[21]

particles

serum simulant

Deionized water;

Paper Chr. grade 2; wax printing

R

Antibody (goat polyclonal)

2 log CFU mL−1

0.531d

 b;

[22]

simulated serum

Ground-water Drinking water, tap

water

River water;

Chromatography paper; wax printing

C

synthetic urine

River water

Cellulose and nitrocellulose membranes;

C

12F6 antibody against

36 nM

[20, 24]

U(VI)-chelator complex

assembling of different layers in a plastic

backing card

0.5 × 4 cm paper; cutting

Hi-Flow Plus nitrocellulose membrane;

assembling of different layers in a plastic

backing card

C C

Cd–EDTA–BSA–AuNP

0.1 ppb

*E. coli*

8 μg L−1

[30]

[23]

Ultrapure water

Filter paper grade 1; cutting by punching

E

Recombinant human

13 ppb (As3+); 45 ppb

[18]

(Hg2+)

0.3 nM

[20]

metallothionein 1a

GR5-DNAzyme

River water River water Surface water

Filter paper grade 1; wax printing

Filter paper grade 1; wax printing

Filter paper discs, 1442-055; cutting by

punching

F E C

Antibody (anti-EE2)

Antibody (anti-EE2)

Enzyme (β-galactosidase)

0.5–6.1 μg L−1

[19]

0.1 ng L−1

0.05 ng L−1

[16]

[17]

**Sample type**

**Paper substrate; fabrication method**

**Detection** 

**Biorecognition element**

**LOD**

**Reference**

**method**

samples were spiked with 10 and 100 ppb of Cd2+, and other 11 metals commonly found in such type of water, containing also EDTA and ovoalbumin (masking agent). An LOD of 0.1 ppb was achieved.

A semiquantitative approach based on a paper-based bacterial biosensor was applied [30] for the detection of arsenite in groundwater samples. It was observed that arsenite produced a visible blue color from substrate of β-galactosidase (reporter protein) at arsenite concentration above 8 μg L<sup>−</sup><sup>1</sup> . Finally, a paper-based lateral flow device was developed for uranium (VI) determination with an LOD (36 nM) below the action level established by the World Health Organization (126 nM) using an immunological competitive approach [24]. These sensors are a suitable tool for field analysis, in opposition to conventional time-consuming and expensive techniques performed under lab environment.

Sensors based on microbial metabolism were developed for application in wastewaters. Pollution peaks, meaning the abrupt change in concentration of organic and metal pollutant in wastewater treatment plants, can compromise the biological treatment phases by killing or inhibiting microorganisms present in sludge. Hence, untargeted sensors were developed using either biofilms [25] or bacteria consortium [26] to report spiking pollution in wastewater influents.

Waterborne pathogens are a major public health as they can lead to several diseases such as cholera, typhoid fever, and dysentery. Hence, accessible, cheap, and disposable analytical tools for monitoring the presence of these pathogens are mandatory, especially in areas with low resources. In this context, an electrochemical paper-based biosensor [28] was developed for the detection of *E. coli* in water, as an indicator of fecal contamination and an indirect indicator of the presumptive presence of other gastrointestinal bacteria. Different *E. coli* strains (both pathogenic and nonpathogenic) were detected in uninoculated and inoculated lagoon water. The method was able to detect as low as 10 CFU mL<sup>−</sup><sup>1</sup> of pathogenic and nonpathogenic *E. coli*.
