Over the past three decades, chemical and biological water contamination has become a major concern, particularly in the industrialized world. Heavy metals, aromatic compounds, and dyes are among the harmful substances that contribute to water pollution, which jeopardies the human health. For this reason, it is of the utmost importance to locate methods for the cleanup of wastewater that are not genuinely effective. Owing to its non-toxicity, biodegradability, and biocompatibility, starch is a naturally occurring polysaccharide that scientists are looking into as a possible environmentally friendly material for sustainable water remediation. Starch could exhibit significant adsorption capabilities towards pollutants with the substitution of amide, amino, carboxyl, and other functional groups for hydroxyl groups. Starch derivatives may effectively remove contaminants such as oil, organic solvents, pesticides, heavy metals, dyes, and pharmaceutical pollutants by employing adsorption techniques at a rate greater than 90%. The maximal adsorption capacities of starch-based adsorbents for oil and organic solvents, pesticides, heavy metal ions, dyes, and pharmaceuticals are 13,000, 66, 2000, 25,000, and 782 mg/g, respectively. Although starch-based adsorbents have demonstrated a promising future for environmental wastewater treatment, additional research is required to optimize the technique before the starch-based adsorbent can be used in large-scale in situ wastewater treatment.

Nowadays there are many alternative methods that have been discovered and developed for the rapid detection of foodborne pathogens that can cause food poisoning. Unfortunately, majority of them still requires improvement in sensitivity and selectivity issues to be of any practical use daily. In this research, biosensors was prepared from 5 µm gap Aluminium interdigitated electrode (Al IDE) to detect Salmonella enterica typhi (S. typhi). The IDE sensors in the biosensor field is extremely interest in these days due to the high number of finger electrodes as comb structure which can gain high sensitivity through electrical measurements. S. typhi is a serious food borne pathogen, makes typhoid disease which causes many deaths annually in worldwide. Functionalization steps of the Al IDE to create biosensor was based on silanization by APTES, immobilization with carboxylic functionalized S. typhi ssDNA probes and blocking agent with tween-20 were the major functionalization steps. The functionalized steps were electrically characterized using current voltage measurements. The selectivity measurement was performed with specific target was identified electrically using complementary, non-complementary and single base mismatch ssDNA target.

This paper investigates E.coli O157:H7 bacteria detection through the electrical based aluminium interdigitated electrode (Al-IDE) biosensor. Functionalization step, silanization process was done using 3-aminopropyl triethoxysilane (APTES). Immobilization process was done using carboxylic probe E.coli. The physical properties of the biosensor were characterized by using low power microscope (LPM), high power microscope (HPM), and atomic force microscopy (AFM). The I-V characteristics were performed for every functionalization step consists of bare Al-IDE, silanization, immobilization, and hybridization. Tween-20 was used as a blocking agent for the nonspecific binding on the non-immobilized area of the biosensor surface. The biosensor was validated with complementary, non-complementary, and single based mismatch ssDNA targets. Different concentrations of complementary target ssDNA from 10 fM tol μM was done for the sensitivity detection. The electrical measurements were done using picoammeter voltage source (Keithley 2450), Kickstart software, and probe station. It confirmed that Al-IDE biosensor is successfully able to detect specific nanoampere range of concentrated E.coli O157:H7 ssDNA targets.