Biogenic capped selenium nano rods as naked eye and selective hydrogen peroxide spectrometric sensor

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Biogenic capped selenium nano rods as naked eye and selective hydrogen peroxide spectrometric sensor Vijay J. Sawanta, , Vikas J. Sawantb ⁎

a b

Department of Chemistry, Smt. K. W. College, Sangli, Maharashtra 416416, India Government Rajaram College, Kolhapur, Maharashtra 416004, India

ARTICLE INFO

ABSTRACT

Keywords: Biogenic Selenium Hydrogen peroxide Sensor

The Biogenic selenium(0) nano rods were synthesized and stabilized in citric acid and flavonoids from lemon juice by wet chemical route. As synthesized nanorods were characterized using physicochemical analysis techniques as UV–Vis, FITR, PXRD spectrometry, SEM and TEM surface morphology imaging techniques. These nano rods had exhibited trigonal Se packing lattice, 90 nm mean crystallite size and surface capping with flavonoid and citric acid functionality. The Se nanorods show selective sensing of peroxide by visible color change from reddish to faint pink and also through spectrometric sensing plots for concentrations from 60 ppm to 5 ppm with sensing limit up to 75 μM peroxide with interfering cellular cations as K, Na, Ca, Mg and Fe. These biogenic green sensor Se nano rods get converted to nano ovals after surface leaching with peroxide and show SPR based selective sensing mechanism in spectrometric plots. These developed nanorods finds suitable applications in biomedical cellular peroxide sensing with low limits through naked eye cost effective spectrometric sensing method.

1. Introduction Silver and gold nanoparticles with variety of shapes have exhibited applications in diverse fields of biomedical, life sciences, chemical and analytical areas including sensing, antioxidant, anticancer potentials. These rod and prism shaped materials require costly precursors for synthesis, instruments and have limitations in actual use because of their cost. The selenium nano materials are suitable alternative for such nanoparticles, as selenium salts, acids are slightly cost effective and easily available. Selenium nanoparticles and nano materials are emerging materials studied in variety of applications in recent trends of research fields of nanotechnology. Especially these nano materials are utilized in biomedical fields. Recent researches of metal nanoparticles exhibits the potential applications of biogenic metal nanoparticles in sensing and anticancer utilities. Biogenic nanoparticles are generally zerovalent metal nanoparticles which are stabilized and synthesized in microbial, plant, algae extracts by green, natural or eco friendly methods. Using these ideas, in this research work we had synthesized selenium nanorods in lemon extract of phytogenic precursor origin for biogenic synthesis. We had used these Se rods for the study of the sensing behavior for cellular ions and peroxide quantities and concentrations based on SPR [Surface Plasmon Resonance] in to ⁎

spectrometric sensing/detection. Hydrogen peroxide sensing is essential aspect as it play significant roles in triggering of various cellular functions. Its concentrations have profound effects on growth and inhibition of cell divisions, mutations in cells. So many researchers had worked on sensing of H2O2 using chemically modified and biogenically synthesized Au, Ag, Pd, Se metal nanoparticles based on electro analytical, spectrometric/colorimetric and probe techniques. But most of these techniques have limitations of costly materials, instruments, method and higher sensing limits for detection of peroxide and have limitations of easy, handy methods. Literature study reveals that most of methods are based on the costly and less effective sensing methods for cellular peroxide detection. M. Yamada et al. [1] had developed chemiluminescence based detection and sensing method for peroxide based on use of complexes and resin. F. Farjami et al. have reported ionic liquids based peroxide sensor [2]. Some research groups have developed silver based electro and probe sensors for peroxide [3,4]. Few researchers in this field have been reported dye and polymer based analytical peroxide sensors for H2O2 [4,5]. Metal oxide and composite nanomaterial based peroxide biosensors are also developed to detect peroxide concentrations using electro analytical techniques [6,7]. Several research groups have been reported metal, metal oxide and nanocomposite based sensors and electro probes for peroxide detection [8–11]. Metal nanoparticles of Au,

Corresponding author. E-mail address: [email protected] (V.J. Sawant).

https://doi.org/10.1016/j.sbsr.2019.100314 Received 19 August 2019; Received in revised form 19 November 2019; Accepted 22 November 2019 2214-1804/ © 2019 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/).

Please cite this article as: Vijay J. Sawant and Vikas J. Sawant, Sensing and Bio-Sensing Research, https://doi.org/10.1016/j.sbsr.2019.100314

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Ag and carbon nanomaterials, along with some metal hydroxide nanocomposites are used as peroxide or hydrogen sensors based on electro analytical and probe techniques [12–17]. As these methods shows costly sensing materials, methods and less sensitive technique approach and higher peroxide detection and sensing limits, So there is need for development of new sensing methods for peroxide sensing having cost effective/green approach, simple, handy characteristics and should have lowest detection limits for peroxide. On continuation with this motivation in analytical research, our developed method contain green biogenic route for synthesis of Se metal nano material, simple, handy, cost effective approach for peroxide sensing with low detection limits. We had studied sensing behavior of lemon precursor synthesized biogenic Se nano material for low detection limits of peroxide with interfering cellular cations. This developed peroxide sensing method may be suitable for sensing of peroxide under biomedical applied techniques, also to detect future peroxide based cancer probabilities in mutating cells. As trace peroxide concentrations affect on mutations of DNA in mammalian type cells, identification of its concentration levels by simple method is essential task for analytical science. So our research work may benefit to biomedical and analytical fields for sensing and detection of peroxide by simple and cost effective method and possess superiority than other sensing methods for peroxide detection.

2.3. Physicochemical characterization for structure, morphology and surface capping The formation, stability and surface capping of biogenic Se nanorods were studied on the basis of UV–Vis and FTIR spectrometric analysis. UV–Vis spectra of nanoparticles was determined with 20 ppm aliquot solution from suspension of ultra fine Se nanorods in Millipore double distilled water and water as blank. The FTIR spectra of dried Se material powder was determined on Perkin Elmer series spectrometer by palette KBr method. The surface capping had been proved by these estimations and then PXRD patterns of material were determined by the PXRD technique with Cu source. The phase purity, packing of Se atoms, surface capping, crystallite size had been estimated from PXRD data by matching with standard JCPDS card. SEM and TEM images of Se nanoparticles were obtained with Cu and carbon grid and mesh, before and after sensing experiments and related to study of morphology, structures and sizes. The SAED patterns of TEM analysis were matched with PXRD data. 2.4. Spectrometric sensing of hydrogen peroxide for various concentrations and selective spectrometric sensing of H2O2 in presence of cellular interfering ions The sensing behavior of Se nano material for cellular cations and peroxide are studied on the basis of SPR light irradiation UV–Vis spectrometric and naked eye color change based simple technique in our research work. Here 25 μl of 20 ppm [about 300 μM] solution/ suspension of Se nano material in double distilled water were successively mixed with 25 μl of analyte solutions of cations and peroxide with concentrations of 5 ppm [about 75 μM] in tubes and then taken in cuvettes to obtain sensing absorbance changes along with using double beam wavelength scanning and water as blank. Then concentrations of H2O2 are varied from 5 ppm to 20, 40 and 60 ppm to determine concentration effect on sensing and to evaluate minimum concentration limit of sensing. Then ΔA absorbance changes of peak maxima [λmax] are related to Log C of concentrations to evaluate sensing plot and sensing selectivity. Higher ΔA changes of analyte were related to sensing selectivity of method with interfering ionic state. Sensing plots are determined to study sensing selectivity of peroxide with cellular cations of Ca, Mg, Na, K, Fe and detection limit for sensing of peroxide also demonstrated using these plots.

2. Experimental section 2.1. Materials and instruments All the chemicals used for synthesis of biogenic Se(0) nanorods were of A. R. grade., selenous acid H2SeO3, Conc. 11 M HCl, NaCl salt used for washing, 20 vol. 6% W/V hydrogen peroxide, calcium chloride, potassium chloride, magnesium chloride, Fe(II) chloride etc. all the chemicals were purchased from S. D. fine chem. Ltd. and Merck ltd and were used without further purification. The fresh lemon was purchased from local market for phyto-biogenic synthesis of Se nano material. The double distilled water was obtained from Millipore system and was used throughout the biogenic synthesis and spectrometric sensing behavior tests with this purified water as blank. The Systronics double beam spectrophotometer with scanning range 190 nm–1100 nm was used for characterization, stability and sensing studies of Se nanorods. The Perkin Elmer series FTIR spectrophotometer is used to elaborate the surface functionalities and surface capping of biogenic Se nano material. The biogenic Se nano material was synthesized using E-tronics magnetic stirrer with hot plate, centrifuge machine, sonicator, and drying oven. The PXRD patterns of Se nanorods were estimated using the PXRD technique with Cu Kα line source. The SEM and TEM images of nanoparticles were determined using Jasco type instruments with carbon mesh and Cu grid techniques.

3. Results and discussion 3.1. Morphological and structural characterization of biogenic selenium ultra fine nano material A] FTIR spectrum proving surface capping: FTIR Spectrum of biogenic Se nano material was determined to elaborate the surface capping and stabilty of Selenium (0). The eOH/ eCOOH citrate capping, eOH and eOe groups of functionalities from citrate entity and presence of flavonoid aromatic entities on surface of Se nanoparticles were confirmed on the basis of spectroscopic data. In the functional group region of FTIR spectrum in Fig. 1; 3343 cm−1, 2918 cm−1, 2308 cm−1 signals were obtained for citrate eCOOH and eCOO groups from citrate and flavonoid as well as ether eOe group present over flavonoid respectively on surface of nano material. The fingerprint region signals of FTIR spectrum with vibrational frequencies of functionalities at 1621 cm−1, 1239 cm−1, 1096 cm−1 are attributed to ketonic eCO, aromatic-metal Se bonds and surface water eOH on Se nano material. The signals at 1018 cm−1, 897 cm−1, 753 cm−1 are obtained due to SeeC and SeeSe metal surface stretching vibrations, proving surface capping on Se nanoparticles. All these spectral evidences relates to surface capping and stabilization of biogenic Se nano material with lemon citrate and flavonoids on surface. These

2.2. Synthesis of Biogenic Selenium(0) ultra fine nanorods in lemon precursors 25 ml of fresh lemon extract was boiled at 95 °C in beaker and then placed in flask and added with 25 ml 0.01 M selenous acid solution in double distilled water. 5 drops of conc. HCL was added to dissolve selenous acid to SeO32− ions, then the contents were subjected to 24 h stirring at 800 rpm, the color change was observed to yellow. Then lemon citric acid and flavonoid stabilizing and capping was taken place after stirring in the flask. The reddish colored Se(0) nanorods were precipitated and then washed with 0.01 M NaCl solution to remove surface chlorides; furthermore material was washed 3 times with double distilled water with centrifugation, then finally precipitate was dried in hot air oven below 80 °C. This Se nano material was dispersed in water and refrigerated in tubes until further use. 2

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FTIR spectra of Se rods capped with citric acid and flavonoids 50.0 48 46 1018.18

1239.16

44

897.90

Se-Ar 1096.50

Se-OH Se-C Se Nano Surface

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%T

40 38 2308.12

36

3343.41

-CO=O -OH/ -COOH Citrate

34 33.0 4000.0

2918.76

3600

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-C=O/ -O-

-C=O Flavonoid-Ar

753.45

Se-Se 2400

2000

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υ

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400.0

cm-1

Fig. 1. FTIR spectrum of biogenic citric acid and flavonoid capped selenium rods.

observations also support to surface plasmon resonance based probable electron transitions in sensing ability for these nano material, as these Se nano material surfaces contain free n and π electrons of citrate and flavonoid functionalities.

follows, Hence the PXRD data reveals the phase purity, surface capping, free electron density over surface, trigonal lattice packing, size below 100 nm, furthermore proving the surface Plasmon resonance [SPR] ability of these nanorods.

B] PXRD (Powder X ray diffraction) pattern of Biogenic selenium nano material:

C] SEM images of original Se nano rods and nano ovals after peroxide leaching:

As per Fig. 2 representing PXRD patterns of biogenic synthesized Se nano material, flavonoid and citrate capped surfaces exhibit high intense, strong and some diffused peaks. The main diffraction peak was obtained in PXRD spectra for (101) plane at 29.8O of 2 theta position. This XRD peak have proved the presence of single phase purity of nano rods with trigonal packing inside Se nanorods. The crystallite size of the nanoparticles was then determined by Scherrer's formula as, K = 0.9λ/ β.COSθ equal to 90–100 nm for biogenic nano material (92 nm from main diffraction peak) Where, β = FWHM of peaks, λ = 1.54 nm, θ = diffraction angle, and K = crystallite size. The surface capping of nano material had shown reduction in electron densities of nanostructure in diffraction, because after flavonoid or citrate coating on surface of Se nanorods the electron density of pure core nano material decreases to cause decrease in peak intensities from JCPDS standard, hence in PXRD pattern the peaks are maintained at respective diffraction angles but intensities are slightly decreased in spectrum. The miller indices, lattice planes and constants representing trigonal metal Se in the nano material are confirmed with the data of JCPDS card no. 6–362 representing same packing and lattice constants as per Table 1 as

SEM images of Se nano mateial before sensing peroxide and after surface chemical leaching and sensing by peroxide are determined to elaborate the surface changing of Se nanoparticles in the sensing and to demonstrate sensing mechanism. The morphology, leaching changes on surface, surface plasmon resonance phenomena, rod to oval strctural conversion for Se nanorods in sensing were demonstrated from SEM images. Fig. 3 represent the SEM image of original biogenic Se nano material with Rod shaped morphology, Fig. 4 represent SEM image of Se nanorods after peroxide sensing and surface leaching to Oval morphology. D] TEM images and SAED patterns of selenium nano material before and after sensing peroxide: The TEM images and SAED patterns of Se nano material before and after peroxide sensing elaborates the presence of correct shapes of nanorods in sensing mechanism and gives idea about probable size of nano material with their structural changes in sensing. TEM image of original Se nanorods in Fig. 5 proves rod shapes and 90–100 nm size range, hence this nanomaterial of Se is surface capped ultra fine Se nanorod shaped biogenic material. SAED patterns of these nanorods in Fig. 5B gives idea of crystalline state of nanoparticles from dotted plane diffraction patterns. Fig. 6 show ovals shapes of Se nano material after peroxide sensing and surface leaching in TEM image, while in Fig. 6 SAED patterns of Se nano ovals after sensing proves conversion of crystalline phase to slight amorphous according to diffuse ring pattern. The TEM size data matches with XRD observations and support to crystal rod state evidences of original Se nano material. SEM and TEM observations matches with evidence of structural changes of Se nano material from rod to oval after peroxide sensing which happen by SPR based spectrometric sensing of peroxide with high ΔA as per next evidences in sensing plots.

Fig. 2. XRD patterns for Se nanorods with trigonal packing. 3

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Table 1 Crystal parameters of biogenic Se nano material matched with standard JCPDS card. Crystallite planes (Miller Indices) (h,k,l) Trigonal packing

d Calculated A0 d = a/√(h2 + k2 + l2) or 2dSinθ = nλ

d Standard A0 JCPDS card no.- 6–362

Lattice Constant a A0 from main XRD peak of Se nano rods

100 101

4.355 3.0482 d used in Scherer's calculation

4.360 3.0496 [θ = 29.8]

3.0387 2.5062 2.4998 1.9534 1.9412

3.0399 2.5146 2.5053 1.9545 1.9433

a/b standard = 4.364 c standard = 4.952 JCPDS 6–362 for t-Se 2θ = 20 to 80O a/b calculated = 4.359 c calculated = 4.949 Trigonal Se(0) nano rods [biogenic Se nano rods]

main diffraction peak/plane

110 102 111 201 210

main diffraction planes of Se nanorod

spectrometric absorption peak analysis at λmax = 273 nm, these characteristic of Se nanoparticles remain stable after 25 days for scanning and absorption peak, which determines stability and surface capping, bonding of functionalities after 25 days. Hence from first two peaks of plots of Fig. 8 it is proved that Se nano material is stable and strongly capped even after 25 days. The peak at λmax = 315 nm raised in spectrum due to surface capping groups on Se nanorods as citrate and lemon flavonoids for n to π* and π to π* free electronic transitions. B] Selective sensing behavior with spectrometric analysis along with interfering cellular ions: As per sensing peaks of UV–Vis spectrometric scanning (Fig. 7) and sensing plots (Fig. 9), higher ΔA values at λmax = 273 nm were obtained for peroxide than cellular interfering ions; hence this evidence proves the higher sensing selectivity of peroxide from Se nano material as nano rods. The lowest concentration limit for peroxide detection and sensing by this method is elaborated as 5 ppm [about 75 μM] from ΔA changes, the Log C against ΔA plot (Fig. 10) and spectrometric sensing behavior. Higher selectivity is observed for sensing of peroxide than other interfering cellular ions by Se nanorods hence its morphology is studied on the basis of TEM and SEM imaging before and after sensing to evaluate sensing mechanism from surface of Se nanorods. The higher interaction of surface of Se nanorods take place with peroxide under sensing and chemical leaching, which take place to produce Se nano ovals after sensing. SPR is key factor at this surface photometric and naked eye colorimetric sensing. Peak maxima of sensing peaks are dampened or slight shifted in lesser amounts for cations while highly dampened and given high ΔA for peroxide after surface interaction. n to π* and π to π* transitions are key electronic transition for sensing absorption maxima [λmax = 273 nm for Se nanorod and λmax = 315 for surface capped groups respectively]. So after sensing of peroxide and cations these peak maxima and peak changes occurs in spectrometric scanning proving surface SPR based sensing abilities of biogenic Se nano material.

Fig. 3. SEM image of original Se nanorods.

C] Effects of various concentrations of peroxide on sensing and concentration limit [sensing plots] The selectivity of sensing for Se nanorods is observed higher for peroxide than cellular cations on the basis of ΔA plotting (Fig. 9). The plot of ΔA against Log C of peroxide concentration (Fig. 10) also gives idea about concentration based surface sensing from se nano material. Here concentration dependant selective sensing of peroxide is observed with lowest limit of sensing as 5 ppm The color changes were observed from reddish- original color of Se nanoparticles to faint pink with increasing concentrations of peroxide in sensing (picture of naked eye visual color change in Fig. 10). So SPR based surface sensing from Se nano material was observed with surface chemical leaching, shape changing and along with visual naked eye color change. So our developed method for selective sensing of peroxide is simple, cost effective,

Fig. 4. SEM image of Se nano ovals after peroxide sensing and surface leaching.

3.2. Naked eye visible color based spectrometric sensing behavior for hydrogen peroxide and selective sensing with interfering cellular ions [relation to sensing plots] A] UV–Vis spectral stability of Se nano material: The stability of biogenic Se nanorods is studied from UV–Vis 4

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Fig. 5. A: TEM image of Se nanorods B: Crystalline SAED patterns of Se nanorods.

Fig. 6. A: TEM image of Se nano ovals after peroxide leaching B: Slight amorphous SAED patterns of Se nano ovals.

handy, practical with low sensing limit of peroxide. So this method may be unique colorimetric based selective sensing method for peroxide with the use of eco friendly synthesized biogenic se nano material.

1.4 1.2 UV-Vis. Abs. maxima for Se nanorod 2+ Sensing Abs. maxima for Ca 2+ Sensing Abs. Maxima for Mg + Sensing Abs. Maxima for Na + Sensing Abs. Maxima for K 2+ Sensing Abs. Maxima for Fe Sensing Abs. Maxima for H2O2 With Se nano oval leaching All at 5 PPM.

Absorbance

1.0 0.8

3.3. SPR based mechanism [SPM] for selective sensing of H2O2 by biogenic Se nano rods and leaching to nano ovals (Scheme 1) As per Scheme 1, Figs. 8 and 10, SPR based concentration dependant mechanism [SPM] is observed for sensing of peroxide and cellular cations by Se nanoparticles. The naked eye color change was observed from reddish to faint pink by Se nano material for peroxide sensing with large ΔA changes in sensing spectrometric plots which are conentration dependant. Hence the Se nano material selectively senses the peroxide concentrations from 60 to 5 ppm range with 5 ppm detection limit with measorable ΔA with logarithic values of C. As per TEM and SEM images original Se nano rods get converted to Se nano ovals prooving surface chemical leaching by peroxide sensing, hence this data elaborates SPR based leaching of surface of Se nanorods in peroxide sensing. So Scheme 1 elaborates the perfect mechanism for sensing behaviour of biogenic capped stable Se nanoparticles for peroxide with interfering cellular cations. Here H2O2 may leach surface of Se nano rods during sensing to remove citrate and flavonoid capping

0.6 0.4 0.2 0.0 200

225

250

275

300

325

350

Absorption Wavelength (nm) Fig. 7. Spectrometric sensing behaviour of Se nanorods for cellular cations and peroxide.

5

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H2O2 Se Nano Rods

Green Approach

Se Nano Ovals 1.4 1.2

SPR based mechanism leaching

UV-Vis. Abs. maxima for Se nanorod 2+ Sensing Abs. maxima for Ca 2+ Sensing Abs. Maxima for Mg + Sensing Abs. Maxima for Na + Sensing Abs. Maxima for K 2+ Sensing Abs. Maxima for Fe Sensing Abs. Maxima for H2O2 With Se nano oval leaching All at 5 PPM.

Absorbance

1.0 0.8 0.6 0.4 0.2 0.0 200

225

250

275

300

325

350

Absorption Wavelength (nm)

Necked eye color change - spectrometric selective sensing

Scheme 1. Mechanism for SPR based SPM selective sensing of peroxide by Se nanorods. Change in A At peak max.

Absorption maxima for Se nanorod at 273 nm. n to Pi

2.0

Plot of sensing selectivity with change in A Fe

Se nanorod stability after 25 days

0.6 Sensing plot for H2O2 with leaching Se nano oval

0.5

at 5 ppm. concentration {SPR}

1.0

2+

Cellular ions and peroxide sensing selectivity at 5 ppm.

0.7

1.5

Absorbance

H2O2

0.8

K

+

Na

+

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Sensing plot for H2O2 with leaching Se nano oval at 20 ppm. concentration {SPR}

0.3

Mg

2+

Sensing plot for H2O2 with leaching Se nano oval

0.2

at 40 ppm. concentration {SPR}

0.5

Sensing plot for H2O2 with leaching Se nano oval

Ca

2+

0.1

at 60 ppm. concentration {SPR}

0.0

0.0 200

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325

Fig. 9. Sensing plot for various cellular cations and peroxide at 5 ppm and sensing selectivity.

350

Absorption Wavelength (nm)

Fig. 8. Selective sensing behaviour of Se nanorods for various peroxide concentrations.

are costly and require critical stages, our method is simple, rapid and handy sensing method with the use of green approach. With the use of this method in our research work peroxide concentrations can be detected up to 75 μM. With use of biogenic Se nano materials which are having stability up to months. Hence method reported in this work is better for cellular peroxide sensing which have advantage of naked eye visual color change detection of peroxide with interfering ions.

and convert shape to nano oval through SPR based n and π electron tunelling in radiation absorption resulting to amorphous Se nano ovals. Overall the SPR based sensing mechanism and chemical surface leaching in sensing had been proved from the spectral and imaging analysis. 3.4. Superiority of our developed method than literature methods based on spectrometric/colorimetric, electro analytical and probe sensing

3.5. Sensing selectivity for peroxide detection by se rods and mechanism for color change from red to faint pink after peroxide surface chemical leaching of se rods to oval shapes

On comparison with literature methods for peroxide sensor with the use of Au, Ag, Pd and Se nano materials, which are based on electro analytical, spectrometric/colorimetric and probe based techniques (as per Table 2), it has been proved that our method is better and superior than other methods for detection/sensing of peroxide with low concentration limits and simple technique. As most of the other techniques

As per Figs. 5, 6, 9, 10 and Scheme 1, it had been proved that 5 ppm concentration of peroxide had been sensed by Se nanorods in presence of interfering cations spectrometrically with naked eye color change detection. During the sensing of peroxide the morphology of biogenic Se nano material changes from nano rod to nano oval, hence this chemical leaching change occurs only for peroxide detection proving high

Table 2 Comparison of literature analytical methods for selective peroxide sensing based on spectrometric/colorimetric, electro analytical and probe sensing with our spectrometric naked eye detection method. Analytical sensing method for peroxide

Physicochemical parameter used in the study

Concentration limit for sensing of peroxide and cost of method

Reference

Ag nanorods CuO nano flowers

Electro analytical response signal Electro chemical

[18] [19]

Gold nano wires Glassy carbon electrode modified with HRP and bacterial Se NPs Microbial Selenium biogenic nano material Our present method [Naked eye color change based spectrometric method by Plant extract Se nanorods]

Electro probe, Spectrometric Electro probe

1 mM high detection limit and costly apparatus 0.05 mM higher detection limit of H2 and peroxide, Costly method 0.1 mM high sensing limit, Less cost effective Use of biogenic Se nano material with electrode, 8 μM, low sensing limit but costly method 70 μM, Low detection limit but costly method 5 ppm [75 μM] of peroxide with interfering Ca2+/K+, Na+, Fe2+, Mg2+ cellular ions, Simple-handy, cost effective

Electro analytical SPR based chemical surface leaching mechanism spectrometric sensing

6

[20] [21] [22] Present study

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Change in A (delta A)

V.J. Sawant and V.J. Sawant 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0

comparison with literature selenium sensors for peroxide and cations, it had been observed that these biogenic Se nano material is superior for naked eye and spectrometric sensing of lowest peroxide concentrations, furthermore which can be applied to biomedical cellular peroxide sensing.

Sensing plot for peroxide concentrations

Declaration of Competing Interest None. Acknowledgements

0.2

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0.4

0.5

0.6

0.7

The authors are greatly thankful to SAIF centre IITB, Mumbai, India for providing some electron microscopic characterizations and to DSTFIST facility centre, Jaysingpur college, India for providing FTIR instrumentation facility. We also acknowledge the support of Principal, Sanjay Bhokare Group of Institutes, Miraj, India for motivational inspiration and providing lab. facility during this research work.

0.8

Log C for (peroxide concentrations in ppm. as 5, 20, 40 and 60 ppm.)

Color change from red to faint pink after peroxide sensingChemical leaching

References [1] S. Hanaoka, J.-M. Lin, M. Yamada, Chemiluminescent flow sensor for H2O2 based on the decomposition of H2O2 catalyzed by cobalt (II)-ethanolamine complex immobilized on resin, Anal. Chim. Acta 426 (2001) 57–64, https://doi.org/10.1016/ S0003-2670(00)01181-8. [2] A. Safavi, F. Farjami, Hydrogen peroxide biosensor based on a myoglobin/hydrophilic room temperature ionic liquid film, Anal. Biochem. 402 (2010) 20–25, https://doi.org/10.1016/j.ab.2010.03.013. [3] Y.-H. Wang, H.-Y. Gu, Hemoglobin co-immobilized with silver–silver oxide nanoparticles on a bare silver electrode for hydrogen peroxide electroanalysis, Microchim. Acta 164 (2009) 41–47, https://doi.org/10.1007/s00604-008-0029-y. [4] S.P. Usha, A.M. Shrivastav, B.D. Gupta, Silver nanoparticle moduled ZnO nano wedge fetched novel FO-LMR based H2O2 biosensor: a twin regime sensor for invivo applications and H2O2 generation analysis from polyphenolic daily devouring beverages, Sensors Actuators B Chem. 241 (2017) 129–145, https://doi.org/10. 1016/j.snb.2016.10.067. [5] P. Bhatia, P. Yadav, B.D. Gupta, Surface plasmon resonance based fiber optic hydrogen peroxide sensor using polymer embedded nanoparticles, Sensors Actuators B Chem. 182 (2013) 330–335, https://doi.org/10.1016/j.snb.2013.03.021. [6] R. Hallaj, S. Soltanian, H. Mamkhezri, Self-assembled Prussian blue nanoparticles based electrochemical sensor for high sensitive determination of H2O2 in acidic media, Electroanalysis 21 (2007) 2355–2362, https://doi.org/10.1002/elan. 200904687. [7] L. Zhang, H. Li, Y. Ni, J. Li, K. Liao, G. Zhao, Porous cuprous oxide microcubes for nonenzymatic amperometric hydrogen peroxide and glucose sensing, Electrochem. Commun. 11 (2009) 812–815, https://doi.org/10.1016/j.elecom.2009.01.041. [8] Y. Wang, X. Chen, J. Zhu, Fabrication of a novel hydrogen peroxide biosensor based on the AuNPs–C@SiO2 composite, Electrochem. Commun. 11 (2009) 323–326, https://doi.org/10.1016/j.elecom.2008.11.056. [9] C. Anjalidevi, V. Dharuman, J. Shankara Narayanan, Non enzymatic hydrogen peroxide detection at ruthenium oxide–gold nano particle–Nafion modified electrode, Sensors Actuators B Chem. 182 (2013) 256–263, https://doi.org/10.1016/j. snb.2013.03.006. [10] M. Kowshik, A. Shriwas, K. Sharmin, W. Vogel, J. Urban, S.K. Kulkarni, K.M. Paknikar, Extracellular synthesis of silver nanoparticles by a silver-tolerant yeast strain MKY3, Nanotechnology 14 (2003) 95–100, https://doi.org/10.1088/ 0957-4484/14/1/321. [11] N. Jia, B. Huang, L. Chen, L. Tan, S. Yao, A simple non-enzymatic hydrogen peroxide sensor using gold nanoparticles-graphene-chitosan modified electrode, Sensors Actuators B 195 (2014) 165–170, https://doi.org/10.1016/j.snb.2014.01. 043. [12] X.C. Song, Y.J. Tong, Y.F. Zheng, H.Y. Yin, Hydrothermal synthesis and electrocatalytic application of the Ag nanorods, Curr. Nanosci. 8 (2012) 608–611, https:// doi.org/10.2174/157341312801784302. [13] X.C. Song, X. Wang, Y.F. Zheng, R. Ma, H.Y. Yin, A hydrogen peroxide electrochemical sensor based on Ag nanoparticles grow on ITO substrate, J. Nanopart. Res. 13 (2011) 5449, https://doi.org/10.1007/s11051-011-0532-7. [14] Y. Zhao, X.C. Song, Synthesis and electrocatalytic property of Ni(OH)2 nanoplates for H2O2 reduction, Micro Nano Lett. 6 (2011) 995–997, https://doi.org/10.1049/ mnl.2011.0555. [15] W. Lian, L. Wang, Y. Song, H. Yuan, S. Zhao, P. Li, L. Chen, A hydrogen peroxide sensor based on electrochemically roughened silver electrodes, Electrochim. Acta 54 (2009) 4334, https://doi.org/10.1016/j.electacta.2009.02.106. [16] F. Valentini, A. Amine, S. Orlanducci, M.L. Terranova, G. Palleschi, Carbon nanotube purification: preparation and characterization of carbon nanotube paste electrodes, Anal. Chem. 75 (2003) 5413, https://doi.org/10.1021/ac0300237. [17] S. Guo, D. Wen, S. Dong, E. Wang, Gold nanowire assembling architecture for H2O2 electrochemical, Talanta 77 (2009) 1510, https://doi.org/10.1016/j.talanta.2008. 09.042.

Fig. 10. Logarithmic concentration dependant selectivity sensing plot of Se rods determining peroxide sensing limit with picture of conversion of Se nanorods to nano ovals.

selectivity of Se nano material to peroxide than other cations. As Se this nano material is selective for sensing peroxide, also it is sensitive to peroxide detection than other cations. It sense peroxide for different concentrations giving different ΔA in sensing plots, so it is more sensitive towards peroxide sensing. In the Fig. 8 as concentration of peroxide changes the peak signal intensities foe absorbance changes to higher ΔA, hence it is selective and sensitive method for peroxide sensing. The color change occurs from reddish to faint pink successively for increase in peroxide concentration, because as Se rods gets leached successively at surface, the flavonoid and citrate coat of capping get removed from surface and size and morphology changes towards nano oval. This mechanism for color change is observed during peroxide sensing by Se nanorods. The SPR based sensing and interaction of surface of Se nanorods to peroxide gives different visible light scattering resulting in to color change along with morphology change by chemical surface leaching. Hence this Se nano material is not only spectrometric but also naked eye visible color change sensor for peroxide. 4. Conclusions The simple and handy naked eye cost effective spectrometric sensor for hydrogen peroxide is developed on the basis of SPR based mechanism using biogenic selenium nano material. The lemon precursor synthesized biogenic selenium nano material with nano rod shapes have been stabilized by citric acid and lemon flavonoids. The physicochemical characterizations of these nano material on the basis of UV–Vis absorption stability and sensing study, FTIR, PXRD spectrometric analysis reveals that; the nano rods shapes of Selenium contain trigonal crystalline packing, surface citric acid and lemon flavonoid capping and good stability for this biogenic nano material. The TEM analysis elaborates that the size matching with XRD data and conversion of original nano rods to nano ovals after peroxide sensing after surface leaching based on Surface Plasmon Resonance, which was selective and higher for peroxide than cellular cationic ions. The selective sensing and spectrometric behavior for peroxide detection which is higher than cations on the basis of UV–Vis spectrometric sensing plots overall exhibits the applications of this biogenic Se nano material for sensing of peroxide with interfering ions at 5 ppm concentration. On 7

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V.J. Sawant and V.J. Sawant [18] X.C. Song, Y.J. Tong, Y.F. Zheng, H.Y. Yin, Hydrothermal synthesis and electrocatalytic application of the Ag nanorods, Curr. Nanosci. 8 (2012) 608–611, https:// doi.org/10.2174/157341312801784302. [19] M. Song, S.W. Hwang, D. Whang, Non-enzymatic electrochemical CuO nanoflowers sensor for hydrogen, Talanta 80 (2010) 1648, https://doi.org/10.1016/j.talanta. 2009.09.061. [20] S. Guo, D. Wen, S. Dong, E. Wang, Gold nanowire assembling architecture for H2O2 electrochemical, Talanta 77 (2009) 1510, https://doi.org/10.1016/j.talanta.2008. 09.042.

[21] T. Wang, L. Yang, B. Zhang, J. Liu, Extracellular biosynthesis and transformation of selenium nanoparticles and application in H2O2 biosensor, Colloids Surf. B: Biointerfaces 80 (1) (2010) 94–102, https://doi.org/10.1016/j.colsurfb.2010.05. 041. [22] K.S. Prasad, V.V. Jayraj, S.S. Sourabh, J. Patel, R. Patel, M. Kumari, F. Jasmini, K. Selvaraj, Microbial selenium nanoparticles(SeNPs) and their application as a hydrogen peroxide biosensor, Appl. Biochem. Biotechnol. 177 (6) (2015) 1386–1393, https://doi.org/10.1007/s12010-015-1814-9.

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