The OPA335 is likely your best choice. It has very high gain and very low offset voltage. The offset voltage is the difference between IN+ and IN- it should ideally be Zero. Non Zero offset will result in some error in your output.
An amplifier can only output a voltage equal to the power supply. So if you are supplying the sensor with 5V and your Arduino is 5V then there will NEVER be an amplifier output that could damage the Arduino.
The circuit show does not require + and - power.
The LM285 is a 1.2Volt reference. The way its connected the output with zero current from the sensor will be 1.2v as the sensor supplies current due to exposure to Ethanol the output of the amplifier rises above 1.2v