Graphene is a thin layer carbon material that has become a hot topic of research during this decade due to its excellent thermal conductivity, mechanical strength, current density, electron mobility and surface area. These extraordinary properties make graphene to be developed and applied in various fields. On this basis, researchers are interested to find out the methods to produce high quality graphene for industrial use. Various methods have been developed and reported to produce graphene. This paper was designed to summarize the development of graphene synthesis methods and the properties of graphene products that were obtained. The application of graphene in the various fields of environment, energy, biomedical, sensors, bio-sensors, and heat-sink was also summarized in this paper. In addition, the history, challenges, and prospects of graphene production for research and industrial purposes were also discussed.

Gelatin has been widely used as an additive in pharmaceutical, cosmetic, and food industry. The similar physical appearance between bovine and porcine gelatin causes an issue for some communities like a Muslim due to awareness of halal food. A Muslim community consider porcine gelatin is non-halal material which must be avoided. So there is a demand to distinguish and labeling the origin source of the gelatin in any products. In turn, it lead to development of a method to identify the source of gelatin. In this study, performance of a modified Quartz Crystal Microbalance (QCM) sensor to identify halal gelatin has been investigated. A QCM sensor was modified by depositing polyaniline/nickel compound on the surface of gold electrode QCM carried out by Layer by Layer (LbL) deposition technique. Bovine and porcine gelatin were measured in demineralized water at pH 9. This modified QCM sensor shows good frequency response to distinguish bovine and porcine gelatin. The measurements gave a negative frequency shifts for bovine gelatin and a positive frequency shifts for porcine gelatin. The modified QCM sensor also worked well in the real sample. This indicates that a modified QCM sensor is very useful and effective technique to distinguish bovine gelatin (halal) from porcine gelatin (non-halal).