RESEARCH DIRECTIONS IN DR. LAI'S LAB
Novel Catalysts for Biodiesel
Biodiesel is defined as a fuel comprising monoalkyl esters of long chain fatty acids derived from vegetable oils or animal fats, either in pure form or mixed in any combination with petroleum-based diesel fuel. Our reserach addresses a critical aspect of current biodiesel production: the catalysts employed for the reaction converting triglycerides to their corresponding fatty acid monoalkyl esters. A variety of catalysts could be employed for generating biodiesel, most commonly from triglycerides present in oils and fats through a process called transesterification. In most cases, however, these catalysts are used in liquid phase and therefore residual amounts are often found in the final composition of the biodiesel which could deleterious to car engine. The ideal catalyst would be easily separated from the reaction without contaminating the product. Our approach will solve the contamination problem by anchoring the catalytic units on solid support, allowing product separation via sedimentation and filtration.
Our research focuses on using cellulosic materials such as nanofibrills to build solid-supported catalysts as illustrated in the image below.
Inverse-Opal Sensing Systems for Detection of Emerging Organic Pollutants
Opals are known as a category of gems, among the most colorful of all despite being composed primarily of silica, a colorless solid with the chemical formula SiO2 (opals have the same chemical composition as window glass and quartz). Their name comes from the Latin word opalus meaning “to see a change of color.” Their color is related to their microstructure, which enables reflection of light of a specific wavelength, while transmitting all other wavelengths, as depicted below.
We are investigating different synthetic pathways to inverse opals, based on silica and titania. We are utilizing a moderate-temperature, energy-efficient fabrication process which makes inverse silica or titania opals attractive systems for sensing applications. Our focus is on detecting emerging organic pollutants at nano to picomolar level using inverse opal sensing systems. The structure of a sensing opal is showed below.
Drug Delivery Devices for a Comprehensive Cancer Therapy
Recent literature reports indicate that failure to therapy followed by relapse in many cancers is associated with the presence of Cancer Stem Cells. Typical cancer removal surgery and chemotherapy does not affect this type of stem cells, as illustrated below.
The fact that malignant tumors are heterogeneous by containing both cancer cells and renewable, potent cancer stem cells, suggests that both types of cells need to be eliminated. A sequential approach would be costly and the time between two different therapeutic steps might be detrimental to patients. Thus, a comprehensive therapeutic approach would simplify the process and reduce time and cost of therapy. We are investigating the ability of multi-drug delivery carriers to eliminate both cancer and cancer stem cells through a multifunctional device strategy, as depicted in the schematic below. While the targeting functionality is necessary for removing side effects of a general distribution of the drug, the ideal career is envisioned as containing imaging features for tumor and career accurate localization.
To fabricate such devices, we are focusing on biocompatible porous particles that could host drugs and therapeutic biological molecules inside the pores, imaging particles inside the pore walls and targeting functionality on the particles exterior.