Oscillating sensor and fluid sample analysis using an oscillating sensor

A flow cell for use in analyzing fluid samples, the flow cell comprising:

• a) sensor comprising a substrate including at least one bore extending therethrough and an oscillating sensing device rigidly mounted to one surface of the substrate over the bore, the sensing device including a first electrode disposed in communication with the at least one bore and a second electrode disposed on the oscillating sensing device opposite the first electrode;
• b) a sealing member secured in a fluid-tight manner to the substrate around the oscillating sensing device;
• and
• c) a flow deliver block secured to the sealing member in a fluid-tight manner opposite the substrate and including a number of fluid dispensing ports formed therein, wherein the oscillating sensing device is mounted by an adhesive flush against the surface of the substrate to completely cover the at least one bore.

A flow cell for use in analyzing fluid samples, the flow cell comprising:

• a) sensor comprising a substrate including at least one bore extending therethrough and an oscillating sensing device rigidly mounted to one surface of the substrate over the bore, the sensing device including a first electrode disposed in communication with the at least one bore and a second electrode disposed on the oscillating sensing device opposite the first electrode;
• b) a sealing member secured in a fluid-tight manner to the substrate around the oscillating sensing device;
• and
• c) a flow deliver block secured to the sealing member in a fluid-tight manner opposite the substrate and including a number of fluid dispensing ports formed therein, wherein the sealing member and the flow delivery block do not contact the oscillating sensing device.

A method of assembling a sensor comprising the steps of:

• a) providing an oscillating sensing device having a first electrode disposed on one side of the device and a second electrode disposed on the device opposite the first electrode;
• and
• b) rigidly securing the oscillating device to a surface of a substrate such that the device completely covers at least one bore formed through the substrate and such that the first electrode is positioned substantially within the at least one bore, wherein the step of rigidly securing the oscillating device to the substrate comprises the steps of:
• i) applying an adhesive to one of a periphery of the oscillating sensing device or a periphery of the at least one bore in the substrate;
• and
• ii) pressing the oscillating sensing device and the substrate into engagement with one another.

A method for analyzing a fluid sample utilizing a flow cell including a substrate including at least one bore extending therethrough, and an oscillating sensing device rigidly mounted to one surface of the substrate over the bore, the sensing device including a first electrode disposed in communication with the at least one bore and a second electrode disposed on the oscillating sensing device opposite the first electrode and a fluid delivery block affixed to and spaced from the substrate over the oscillating sensing device by a sealing member, the method comprising the steps of:

• a) introducing at least one guide fluid stream into the flow cell through the fluid delivery block to flow over the oscillating sensing device to generate a hydrostatic pressure value within the flow cell;
• b) introducing at least one sample fluid stream into the flow cell through the flow delivery block at a location separate from the at least one guide fluid stream to flow over the oscillating sensing device;
• and
• c) reducing the flow rate of the at least one guide fluid stream simultaneously with the introduction of the at least one sample fluid stream to maintain the hydrostatic pressure value within the flow cell constant.

A method for analyzing a fluid sample utilizing a flow cell including a sensing device disposed within the flow cell and a fluid delivery block configured to direct multiple fluid streams into the flow cell over the sensing device, the method comprising the steps of:

• a) introducing at least one guide fluid stream into the flow cell through the fluid delivery block to flow over the sensing device to generate a hydrostatic pressure value within the flow cell;
• b) introducing a sample fluid stream into the flow cell through the flow delivery block at a location separate from the at least one guide fluid stream to flow over the sensing device;
• and
• c) reducing the flow rate of the at least one guide fluid stream simultaneously with the introduction of the sample fluid stream to maintain the hydrostatic pressure value within the flow cell constant.