Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Sameena Mehtab is active.

Publication


Featured researches published by Sameena Mehtab.


Talanta | 2006

A bromide selective polymeric membrane electrode based on Zn(II) macrocyclic complex

Ashok Kumar Singh; Sameena Mehtab; Puja Saxena

A novel bromide ion-selective PVC membrane sensor based on 2,3,10,11-tetraphenyl-1,4,9,12-tetraazacyclohexadeca-1,3,9,11-tetraene zinc(II)complex (I) as carrier has been developed. The electrode exhibited wide working concentration range 2.2 x 10(-6) to 1.0 x 10(-1)M and a limit of detection as 1.4 x 10(-6)M with a Nernstian slope of 59.2+/-0.5 mV per decade. The response time of electrode was 20s over entire concentration range. The electrode possesses the advantages of low resistance, fast response and good selectivities for bromide over a variety of other anions and could be used in a pH range of 3.5-9.5. It was successfully used as an indicator electrode in the potentiometric titration of bromide ions with silver ion and also in the determination of bromide in real samples.


Talanta | 2006

Strontium(II)-selective electrode based on a macrocyclic tetraamide.

Ashok Kumar Singh; Puja Saxena; Sameena Mehtab; Barkha Gupta

A new PVC membrane electrode based on 5,7,12,14-dibenzo-2,3,9,10-tetraoxa-1,4,8,11-tetraazacyclotetradecane (I) as an ion carrier, o-nitrophenyloctyl ether (o-NPOE) as solvent mediator and sodium tetraphenylborate (NaTPB) as lipophilic additive was fabricated and investigated as Sr(2+)-selective electrode. The best performance was exhibited by the membrane having composition 8:200:4:120 (I:o-NPOE:NaTPB:PVC). The electrode exhibited a Nernstian response for strontium ion over a wide concentration range 3.98 x 10(-6) to 1.0 x 10(-1)M with a slope of 29.0+/-0.1 mV/decade of concentration and a detection limit of 2.82 x 10(-6)M. It showed a response time of less than 10s and could be used for at least 3 months without any divergence in potential. The proposed electrode showed a good discriminating ability towards strontium(II) ion over a wide variety of other metal ions including alkali, alkaline earth, transition, and heavy metal ions. The electrode can be used in the pH range of 2.5-10.5 and in mixtures containing up to 35% (v/v) non-aqueous content. It was used as an indicator electrode in potentiometric titration of strontium ion against EDTA.


Analytica Chimica Acta | 2009

Development of electrochemical sensors for nano scale Tb(III) ion determination based on pendant macrocyclic ligands

Ashok Kumar Singh; Prerna Singh; Shibdas Banerjee; Sameena Mehtab

The two macrocyclic pendant ligands 3,4,5:12,13,14-dipyridine-2,6,11,15-tetramethyl-1,7,10,16-tetramethylacrylate-1,4,7,10,13,16-hexaazacyclooctadeca-3,13-di ene (L(1)) and 3,4,5:12,13,14-dipyridine-2,6,11,15-tetramethyl-1,7,10,16-tetra(2-cyano ethane)-1,4,7,10,13,16-hexaazacyclooctadeca-3,13-diene (L(2)) have been synthesized and explored as neutral ionophores for preparing poly(vinylchloride) (PVC) based membrane sensors selective to Tb(III) ions. Effects of various plasticizers and anion excluders were studied in detail and improved performance was observed. The best performance was obtained for the membrane sensor having a composition of L(1): PVC:1-CN:NaTPB in the ratio of 6: 32: 58: 4 (w/w; mg). The performance of the membrane based on L(1) was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Tb(3+) ions with limits of detection of 3.4 x 10(-8)mol L(-1) for PME and 5.7 x 10(-9)mol L(-1) for CGE. The response time for PME and CGE was found to be 10s and 8s, respectively. The potentiometric responses are independent of the pH of the test solution in the pH range 3.0-7.5 for PME and 2.0-8.5 for CGE. The CGE has found to work satisfactorily in partially non-aqueous media upto 30% (v/v) content of methanol, ethanol and 20% (v/v) content of acetonitrile and could be used for a period of 5 months. The CGE was used as indicator electrode in the potentiometric titration of Tb(3+) ions with EDTA and in determination of fluoride ions in various samples. It can also be used in direct determination of Tb(3+) ions in tap water and various binary mixtures with quantitative results.


International Journal of Environmental Analytical Chemistry | 2009

Development of an electrochemical sensor based on Schiff base for Cu(II) determination at nano level in river water and edible materials

Ashok Kumar Singh; Ajay K. Jain; Jitendra Singh; Sameena Mehtab

Plasticised membranes using 2-[{(2-hydroxyphenyl)imino}methyl]-phenol (L1) and 2-[{(3-hydroxyphenyl)imino}methyl]-phenol (L2), have been prepared and investigated as Cu2+ ion-selective sensors. Effect of various plasticisers, namely, dibutyl phthalate (DBP), dibutyl sebacate (DBS), benzyl acetate (BA), o-nitrophenyloctylether (o-NPOE) and anion excluders, oleic acid (OA) and sodium tetraphenylborate (NaTPB) was studied and improved performance was observed in several instances. Optimum performance was observed with membranes of (L1) having composition L1 : DBS : OA : PVC in the ratio of 6 : 54 : 10 : 30 (w/w, %). The sensor works satisfactorily in the concentration range 3.2 × 10−8–1.0 × 10−1 mol L−1 with a Nernstian slope of 29.5 ± 0.5 mV decade−1 of a cu2+ . The detection limit of the proposed sensor is 2.0 × 10−8 mol L−1 (1.27 ng mL−1). Wide pH range (3.0–8.5), fast response time (7 s), sufficient (up to 25% v/v) non-aqueous tolerance and adequate shelf life (3 months) indicate the utility of the proposed sensor. The potentiometric selectivity coefficients as determined by matched potential method indicate selective response for Cu2+ ions over various interfering ions, and therefore could be successfully used for the determination of copper in edible oils, tomato plant material and river water.


Analytica Chimica Acta | 2006

A cobalt(II)-selective PVC membrane based on a Schiff base complex of N,N′-bis(salicylidene)-3,4-diaminotoluene

Vinod Kumar Gupta; Ashok Kumar Singh; Sameena Mehtab; Barkha Gupta


Talanta | 2008

Polymeric membrane sensors based on Cd(II) Schiff base complexes for selective iodide determination in environmental and medicinal samples.

Ashok Kumar Singh; Sameena Mehtab


Sensors and Actuators B-chemical | 2007

Thiocyanate selective sensor based on tripodal zinc complex for direct determination of thiocyanate in biological samples

Ashok Kumar Singh; Udai P. Singh; Sameena Mehtab; Vaibhave Aggarwal


Sensors and Actuators B-chemical | 2007

Calcium(II)-selective potentiometric sensor based on α-furildioxime as neutral carrier

Ashok Kumar Singh; Sameena Mehtab


Analytica Chimica Acta | 2005

Rubeanic acid as novel carrier in construction of selective membrane sensor for La(III)

Ajay K. Jain; Ashok Kumar Singh; Sameena Mehtab; Puja Saxena


Sensors and Actuators B-chemical | 2007

A novel potentiometric membrane sensor for determination of Co2+ based on 5-amino-3-methylisothiazole

Ashok Kumar Singh; Sameena Mehtab; Puja Saxena

Collaboration


Dive into the Sameena Mehtab's collaboration.

Top Co-Authors

Avatar

Ashok Kumar Singh

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

Puja Saxena

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

Udai P. Singh

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

Vaibhave Aggarwal

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

Ajay K. Jain

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

Barkha Gupta

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

A.K. Singh

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

Amit Panwar

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

Jitendra Singh

Indian Institute of Technology Roorkee

View shared research outputs
Top Co-Authors

Avatar

Prerna Singh

Indian Institute of Technology Roorkee

View shared research outputs
Researchain Logo
Decentralizing Knowledge