Devices and Methods Including Materials Such as Functionalized Cellulose for the Detection of Analytes

Embodiments described herein provide devices and methods for the determination of analytes. The device typically includes an absorbent material that allows for an analyte sample to be concentrated and analyzed simultaneously and within a short period of time (e.g., less than 10 seconds). Embodiments described herein can provide portable and easily operable devices for on-site, real time field monitoring with high sensitivity, selectivity, and fast response time.