Access data entry continuous form containing bound and unbound controls

I work in a laboratory and would like to create a data entry form to inventory specimens. Each specimen will be stored in a freezer box. This box contains 81 positions to store unique specimens. All 81 unique specimens share common characteristics. I have created a continuous form with the following combo boxes in the header:

ComboBoxID
ComboAnalyte
ComboSpecimenMatrix
ComboYear
ComboFreezer
ComboShelf
ComboRack
ComboBox

These Combo boxes are shared with all 81 unique specimens and are associated with unbound text boxes located in the form's detail section. In the detail section I have also created a bound textbox to record the specimen unique identifier (barcode number) and a bound combo box to select the volume present in the specimen tube. There is also an unbound textbox that populates the box position automatically/consecutively as I enter the specimen number.

Here is my problem. I cannot figure out how to append the information contained in the unbound textboxes to the table containing the information from the bound textboxes. I have tried creating a bound continuous form, but do not want to select the 8 shared characteristics for all 81 specimens. My goal is to quickly scan all 81 specimen bar codes and easily select the defining characteristics at once for all specimens.

Any help would be greatly appreciated.