Modified Surface Relief Layer Created by Holographic Lithography: Application to Selective Sodium and Potassium Sensing

Modified Surface Relief Layer Created by Holographic Lithography: Application to Selective Sodium and Potassium Sensing

Blog Article

Point-of-care diagnostics will rely upon the development of low-cost, noncomplex, and easily integrated systems in order to examine biological samples such as blood and urine obtained from the patient.The development of metal ion sensors is a subject of significant rachel bati relevance for physiological samples.The level of different blood electrolytes, mainly H+, Na+, K+ and Cl− is considerably used to monitor irregular physiologies.

The particular challenge in biosensing, and in fact for any other sensor, is signal differentiation between non-specifically bound material and the specific detecting of the target molecule/ion.The biosensors described in this paper are fabricated by a holographic recording of surface relief structures in a photopolymer material.The surface structures are modified by coating with either dibenzo-18-crown-6 (DC) or tetraethyl 4-tert-butylcalix[4]arene (TBC), which are embedded in a polymer matrix.

Interrogation of these structures by light allows indirect measurement of the concentration of the analyte.The influence of polymer matrices with different porosities, plasticised polyvinyl chloride (PVC) and a sol-gel matrix, on the performance of the sensors for detection of K+ and Na+ is examined.Here we demonstrate a proof of concept that by using a matrix with higher porosity one can increase the sensitivity of the sensor.

The results showed that the DC sensing layer provides a selective response to K+ over Na+ and the TBC modified grating is more responsive carlsbad crush to Na+ over K+.The sensor responds to K+ and Na+ within the physiological concentration ranges.