Zalhan Md Yusof

An assessment study of absorption effect: LED vs tungsten halogen lamp for noninvasive glucose detection

Noninvasive glucose monitoring development is critical for diabetic patient continuous monitoring. However, almost all the available devices are invasive and painful. Noninvasive methods such as using spectroscopy have shown some good results. Unfortunately, the drawback was that the tungsten halogen lamps usage that is impractical if applied on human skin. This paper compared the light emitting diode (LED) to traditional tungsten halogen lamps as light source for glucose detection where the type of light source plays an important role in achieving a good spectrum quality. Glucose concentration measurement has been developed as part of noninvasive technique using optical spectroscopy. Small change and overlapping in tungsten halogen results need to replace it with a more convenient light source such as LED. Based on the result obtained, the performance of LED for absorbance spectrum gives a significantly different and is directly proportional to the glucose concentration. The result shows a linear trend and successfully detects lowest at 60 to 160 mg/dL glucose concentration.

Noninvasive glucose level determination using diffuse reflectance near infrared spectroscopy and chemometrics analysis based on in vitro sample and human skin

Fourier Transform Near Infrared Spectroscopy (FT-NIRS) is a bright method to estimate glucose concentration level by detecting glucose molecular properties in tissue and blood. NIRS technique consists of many method measurements including diffuse reflection method. It capable to predict blood glucose level in human blood noninvasively without pain. However the main weakness of FT-NIRS is the low absorption spectrum of glucose and not a straight forward signal for quantification analysis. Therefore, preprocessing data and chemometrics analysis is required to enhance the spectrum performance and identified certain chemical information present in the sample. The main objective in this paper is to evaluate the potential of low level detection using FT-NIRS towards glucose spectrum in water and intralipid. This study also observed the relationship between human skin spectrums with its blood glucose level value. Utilizing a few preprocessing method and PLS regression technique, Root Mean Square Error Cross Validation (RMSECV) and Coefficient of determination Cross validation (R2CV) were observed to validate the model. RMSECV obtained for glucose in water and intralipid were 47.05 mg/dl (2.6 mmol) and 31.17 mg/dl (1.7 mmol) respectively. Meanwhile R2CV achieved for glucose in water and intralipid were at 0.94 and 0.97 respectively. The Clarke Error Grid shows 97% of the measurement fell within zone A and B. This study has shown that, glucose detection was possible to be monitored in human blood by using FT-NIRS and PLS regression analysis.

Feasibility study of detecting canola oil adulteration with palm oil using NIR spectroscopy and multivariate analysis

Detection of adulteration in food is one of the most important issues in food industry today. In this study, the feasibility of classifying canola oil samples from the one adulterated with palm oil using NIR spectroscopy in combination with multivariate analysis is investigated. An experiment to obtain the NIR spectra was conducted and analyzed using multivariate analysis. The result using open source R software has shown that adulterated oil samples could be detected with an overall correct classification rate of 100 % with minimum detection level of 3.23 %.

Photon counting polarimetry measurement towards non-invasive biomedical glucose monitoring

Commercially available glucose measurement device for diabetes monitoring require extracting of blood and this means there will be a physical contact with human body. Demand on non-invasive measurement has invites research and development of new detection methods to measure blood glucose level. In this work, a very sensitive optical polarimetry measurement technique using ratio-metric photon counting detection has been introduced and tested for a range of known glucose concentrations that mimic the level of glucose in human blood. The setup utilizes 785nm diode laser that emits weak coherent optical signal onto glucose concentration samples in aqueous. The result shows a linear proportional of different glucose concentration and successfully detected 10260 mg/dl to 260 mg/dl glucose samples. This indicates a potential improvement method for non-invasive glucose measurement by a sensitive polarimetry based optical sensor in single photon level for biomedical applications.

Design of fourier transform infrared optical sensor with manufacturing tolerance on interferometer arms for application on non-invasive hypoglycemia and hyperglycemia detection

An interferometer design employing a broadband source and based on optical fiber as waveguide implementation for contactless optical detection meant for biomedical sample is presented. The interferometer design and simulation is done using OptiSystem software. Manipulation of phase difference to produce interferogram centerburst was contributed by the optical time delay and the optical fiber length at both interferometer arms. The design is varied by time delay and it produced proper centerburst at zero optical path difference without significant affect by manufacturing tolerance length of optical fiber at both interferometer arms. It is observed that interferograms centerburst will be remained at zero nanosecond time delay up to 0.5% manufacturing tolerance length and will be shifted to the left or right position depending on the minus or plus of the tolerance length.

Analysis of passive compensation for linear and non linear SOP on standard single mode optical fiber

We report experimental result on passive compensation on standard single mode optical fiber. The states of polarization (SOP) were analysed and the six main states normally used for QKD system are investigated. Passive control of SOP approach seems very unpractical, but through simple setup, compensation at each communicating arm seems to be a potential method. The results show that the SOP state remains similar to the source after compensation and the passive compensation setup compensate all 6 SOPs source value over time. We achieved to maintain the related stoke value (S1, S2, S3) at each SOP state above 93%.

A comparative study of photocurable sensing membrane for Potassium ChemFET sensor

The availability of in-house microelectronic fabrication technology has given an opportunity for the development of chemical sensor based on field effect transistor (FET). Chemical sensing material deposited on the FET device is developed to explore the function as chemically sensitive field effect transistor (ChemFET) for the detection of specific analyte for agriculture and aquaculture applications. In this work, photocurable method was used to develop sensing membrane for Potassium ChemFET (K ChemFET) sensor. Urethane- and Acrylate-based host matrix polymer was selected for a comparative study as a sensing membrane for potassium ion detection. The performance of the sensor was characterized according to its sensitivity and selectivity. Performance test for K ChemFET sensor using both membrane types showed a comparable result with commercial K sensor with sensitivity of near Nernstian value and good linearity (> 0.99) in the range of 10-4 to 10-1 M calibration solution. Selectivity test demonstrated that K Acrylate-based ChemFET with one fold higher than K Urethane-based ChemFET towards Na+, Ca2+ and Mg2+ interfering ions.

Improvement on advanced security network module on real telecommunication infrastructure

We successfully implement and improved Advanced Security Network Module on real fiber optic test-bed by riding on existing laid telecommunication fiber. Transmitting through dark fiber was achieved with a maximum key rate of 2056 bit/s that unconditionally protects the establishment of shared keys between two remote distances. Mixing of Telecom standard single mode fiber type which consist of normal G652 and low water peak fiber G652D, Fresnel reflection and the effect of train passing by on some portion of the entire 44.5km length are among the obstacles while deploying the security network module equipment.