Sample handling comprises two critical aspects to ensure accurate results - storage and transportation.  

Transportation refers to the process of moving samples to the laboratory without any change in their physical or chemical characteristics. During the transport, depending on the sample's nature, preservation techniques like freezing and chemical preservation may be required to prevent changes.

For example, freezing prevents the thermal degradation of samples sensitive to temperature. The addition of chemical preservatives like antibacterial agents to samples prevents microbial growth.

In the laboratory, proper storage of samples is essential to prevent sample degradation. For example, thermally labile samples are packed in sealed containers, stored in refrigerators, or frozen.

The liquid samples sensitive to light must be stored in dark environments or amber bottles.