PolyU Science in the News

PolyU stages Knitwear Fashion Show

The creative flair and design talent of graduating students from The Hong Kong Polytechnic University (PolyU)'s Institute of Textiles and Clothing (ITC) received an over-whelming response and appreciation from the industry at the Annual Knitwear Fashion Show held today (30 May) at The Mira Hong Kong. With the concerted effort of ITC design students, PolyU and various knitwear producers and yarn suppliers, the annual Knitwear Fashion Show showcased 22 collections of four outfits from 22 graduating students majoring in knitwear design. The raw materials and manufacturing techniques for the show were sponsored by knitwear producers and yarn suppliers. Professor John H. Xin, Head and Chair Professor of ITC, said, "This is the eighth successive year for ITC to organise the Knitwear Fashion Show. We are thrilled to receive enormous support from the industry throughout the years. Apart from providing a platform for the students to demonstrate their creativity and talent, the Show also helps in strengthening the connection and building a long lasting partnership between ITC and the industry. ITC will continue to nurture talented professionals for the industry and to support sustainable development of the knitwear industry." As the sole provider of tertiary education in fashion and textiles in Hong Kong, ITC offers exciting opportunities to those who wish to pursue careers in the dynamic fashion and textiles industry. Since its inception in 1957, ITC is committed to educational training and development for the advancement of the Hong Kong fashion and textile industry through various research and scholarly activities.

PolyU Develops Novel Nano Biosensor for Rapid Detection of Flu Virus

The Department of Applied Physics (AP) and Interdisciplinary Division of Biomedical Engineering (BME) of The Hong Kong Polytechnic University (PolyU) have jointly developed a novel nano biosensor for rapid detection of flu and other viruses. PolyU's new invention utilizes an optical method called upconversion luminescence resonance energy transfer (LRET) process for ultrasensitive virus detection. It involves simple operational procedures, significantly reducing its testing duration from around 1-3 days to 2-3 hours, making it more than 10 times quicker than traditional clinical methods. Its cost is around HK$20 per sample, which is 80% lower than traditional testing methods. The technology can be widely used for the detection of different types of viruses, shedding new light on the development of low-cost, rapid and ultrasensitive detection of different viruses. Traditional biological methods for flu virus detection include genetic analysis -- reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) used in immunology. However, RT-PCR is expensive and time-consuming while the sensitivity for ELISA is relatively low. Such limitations make them difficult for clinical use as a front-line and on-site diagnostic tool for virus detection, paving the way for PolyU's development of the new upconversion nanoparticle biosensor which utilizes luminescent technique in virus detection. PolyU's researchers have developed a biosensor based on luminescent technique which operates like two matching pieces of magnet with attraction force. It involves the development of upconversion nanoparticles (UCNPs) conjugated with a probe oligo whose DNA base pairs are complementary with that of the gold nanoparticles (AuNPs) flu virus oligo. Given the complementary nature of the DNA base pairs of the UCNPs probe oligo and AuNPs flu virus oligo, they work like two matching pieces of magnet, which would be drawn together due to attraction force. This process is also called oligo hybridization. Upon being illuminated by a portable near-infrared laser pen, the UCNPs emit eye-visible green light while the AuNPs would absorb the green light. One can easily quantify the concentration of the targeted flu virus by measuring the decrease in the green light intensity. Initially, PolyU researchers have utilized upconversion LRET for ultrasensitive virus detection in liquid phase system. The research team has further improved the sensitivity of the luminescent detection method by utilizing a solid phased nanoporous membrane system (NAAO) for virus detection. As NAAO membrane consists of many hollow channels, they allow more space for oligo hybridization to take place, significantly increasing its sensitivity by more than 10 folds compared to the liquid phase system, proven by clinical detection using inactivated virus samples. Not only is the design and operation of PolyU's invention simple, it does not require expensive instruments and sophisticated operational skills, with its sensitivity comparable to traditional clinical methods. In comparison to conventional downconversion luminescent technique, it causes low damage to genetic materials and does not induce background fluorescence. In addition, since each virus has a unique genetic sequence, researchers would be able to design a complementary probe once the genetic sequence of the targeted virus is known. In other words, the upconversion LRET technology can be widely used for the detection of different types of viruses simply by modifying the UCNPs capture probe. The related results have been recently published in ACS Nano and Small, two leading journals in nano material research. With the support from the Innovation and Technology Support Programme, the research team will continue to enhance the nano biosensor for rapid virus detection, which includes increasing its sensitivity and specificity, and developing a matrix for detection of multiple flu viruses on a single testing platform.

PolyU Develops Fluorescent Probes for Rapid Detection of Formaldehyde in Food

The Department of Applied Biology and Chemical Technology (ABCT) of The Hong Kong Polytechnic University (PolyU) has developed fluorescent probes for rapid detection of formaldehyde in food. In recent years, formaldehyde has been discovered to be illegally used in food processing for bleaching and preservation purposes, arousing health concerns by the general public. PolyU's highly selective formaldehyde rapid detection method involves only simple procedures. It can test 10 food samples on-site in one go in comparison to traditional methods which entail 30 minutes for the testing of each food sample one by one. Its cost is less than HK$30, which is 90% lower than traditional testing methods. If the food sample contains formaldehyde, under hand-held UV light, the fluorescent probes will appear to be fluorescent blue, which can be easily observed by naked eyes. Traditional methods for formaldehyde measurement are liquid chromatography which involves chemical derivation of formaldehyde, chromatographic separation and instrumental analysis of the formaldehyde content with reference to the sample standard. However, these methods require expensive instruments, sophisticated operational skills, tedious sample preparation and time-consuming analysis. Given their low testing through-put, the testing of 10 food samples would require up to 5 hours (10 X 30 minutes), making these methods not suitable for on-site food safety inspection. In addition, the test results of formaldehyde testing kits available in the market are easily interfered by irrelevant substances. Their low selectivity and stability make them difficult to satisfy the on-site food safety inspection and high through-put needs of the industry and authorities. Based on prior research on a chemical reaction that enables chemical coupling of 1) amine-functionalized resins, 2) formaldehyde and 3) fluorescent dyes via gold catalysis, PolyU researchers have developed fluorescent probes for rapid detection of formaldehyde in food with excellent selectivity and high stability. Firstly, researchers added pre-treated food samples, amine-functionalized resins, fluorescent dyes and gold catalysts into a container, and heated the solution at 50 oC for 1 hour. After that, organic solvents were added to wash out excessive reagents. The three-component coupling reaction will connect resin-linked sterically bulky amines and fluorescent alkynes through chemical bonding with formaldehyde in food so that the surface of the resins will give out fluorescent blue colour under hand-held UV light. One can easily detect the formaldehyde concentration by observing the brightness of the fluorescent colour by naked eyes. Not only is the design and operation of PolyU's invention simple, it does not require expensive instruments and sophisticated operational skills. It can test 10 food samples in one go, making it an ideal solution for on-site food safety inspection and front-line quality control. The research was conducted by ABCT in collaboration with Guangdong Entry-Exit Inspection and Quarantine Bureau. The related paper has been recently published in Organic & Biomolecular Chemistry, a leading journal in Organic Chemistry. A joint PolyU-GDCIQ China patent has been filed. The research team will continue to enhance the formaldehyde rapid detection method, which include developing a new class of tunable fluorescent dyes and developing high through-put rapid detection formats.