TY  - JOUR
A1  - Molinnus, Denise
A1  - Drinic, Aleksander
A1  - Iken, Heiko
A1  - Kröger, Nadja
A1  - Zinser, Max
A1  - Smeets, Ralf
A1  - Köpf, Marius
A1  - Kopp, Alexander
A1  - Schöning, Michael Josef
T1  - Towards a flexible electrochemical biosensor fabricated from biocompatible Bombyx mori silk
JF  - Biosensors and Bioelectronics
Y1  - 2021
U6  - http://dx.doi.org/10.1016/j.bios.2021.113204
SN  - 0956-5663
VL  - 183
IS  - Art. 113204
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Jablonski, Melanie
A1  - Münstermann, Felix
A1  - Nork, Jasmina
A1  - Molinnus, Denise
A1  - Muschallik, Lukas
A1  - Bongaerts, Johannes
A1  - Wagner, Torsten
A1  - Keusgen, Michael
A1  - Siegert, Petra
A1  - Schöning, Michael Josef
T1  - Capacitive field‐effect biosensor applied for the detection of acetoin in alcoholic beverages and fermentation broths
JF  - physica status solidi (a) applications and materials science
N2  - An acetoin biosensor based on a capacitive electrolyte–insulator–semiconductor (EIS) structure modified with the enzyme acetoin reductase, also known as butane-2,3-diol dehydrogenase (Bacillus clausii DSM 8716ᵀ), is applied for acetoin detection in beer, red wine, and fermentation broth samples for the first time. The EIS sensor consists of an Al/p-Si/SiO₂/Ta₂O₅ layer structure with immobilized acetoin reductase on top of the Ta₂O₅ transducer layer by means of crosslinking via glutaraldehyde. The unmodified and enzyme-modified sensors are electrochemically characterized by means of leakage current, capacitance–voltage, and constant capacitance methods, respectively.
KW  - acetoin
KW  - acetoin reductase
KW  - alcoholic beverages
KW  - biosensors
KW  - capacitive field-effect sensors
Y1  - 2021
U6  - http://dx.doi.org/10.1002/pssa.202000765
SN  - 1862-6319
VL  - 218
IS  - 13
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Oliveira, Danilo A.
A1  - Molinnus, Denise
A1  - Beging, Stefan
A1  - Siqueira Jr, José R.
A1  - Schöning, Michael Josef
T1  - Biosensor Based on Self-Assembled Films of Graphene Oxide and Polyaniline Using a Field-Effect Device Platform
JF  - physica status solidi (a) applications and materials science
N2  - A new functionalization method to modify capacitive electrolyte–insulator–semiconductor (EIS) structures with nanofilms is presented. Layers of polyallylamine hydrochloride (PAH) and graphene oxide (GO) with the compound polyaniline:poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PANI:PAAMPSA) are deposited onto a p-Si/SiO2 chip using the layer-by-layer technique (LbL). Two different enzymes (urease and penicillinase) are separately immobilized on top of a five-bilayer stack of the PAH:GO/PANI:PAAMPSA-modified EIS chip, forming a biosensor for detection of urea and penicillin, respectively. Electrochemical characterization is performed by constant capacitance (ConCap) measurements, and the film morphology is characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM). An increase in the average sensitivity of the modified biosensors (EIS–nanofilm–enzyme) of around 15% is found in relation to sensors, only carrying the enzyme but without the nanofilm (EIS–enzyme). In this sense, the nanofilm acts as a stable bioreceptor onto the EIS chip improving the output signal in terms of sensitivity and stability.
KW  - capacitive electrolyte–insulator–semiconductor sensors
KW  - graphene oxide
KW  - layer-by-layer technique
KW  - nanomaterials
KW  - polyaniline
Y1  - 2021
U6  - http://dx.doi.org/10.1002/pssa.202000747
SN  - 1862-6319
N1  - Corresponding author: José R. Siqueira Jr & Michael J. Schöning
VL  - 218
IS  - 13
SP  - 1
EP  - 9
PB  - Wiley-VCH
CY  - Weinheim
ER  -