*5.3. Future Challenges*

The next generation of inorganic particulates and membrane materials could be intended for flow regulation, screening of size, and dynamic pore sizing by means of external controls. Another possibility for fabricating these inorganic particulates and membranes is by the use ofa lab on chip microfluidic model to be used in medical diagnostics. Surface modification of inorganic particulates and membranes with organic and inorganic materials is now being explored. Moreover, when the surface of the inorganic particulates and membranes is modified with grafted polymers, in vitro testing shows promising results. Surface modification using polymers which undergoes conformational changes with a response to stimuli such as temperature, pH, and concentration of ions has shown acceptable results as well. The in vivo tests are necessary to confirm e ffective delivery and biocompatibility. Many challenges are there in manufacturing biocompatible inorganic particulates and membranes for in-vivo drug delivery applications. The key challenge is to fabricate inorganic particulates and membranes which respond to various stimuli. These inorganic particulates and membrane systems could therefore be used in micro/nanoscale chips for rate-controlled programmable delivery of drugs.
