Estelle Morin worked on the concepts of "Meaning of work", "Meaningfulness of work" and "Meaningfulness at work". You can find some of her work here : http://www.irsst.qc.ca/media/documents/pubirsst/r-585.pdf

Have you considered couching it within a framework of Hackman & Oldham's Job Characteristics Model? Meaningfulness is represented therein as a mediating critical psychological state, so could be a good place to start.

Dear colleague,

The psychological construct "calling" is gathering interest in the field of vocational psychology and it may provide some alternative perspectives for your research.  Note that calling in the following papers is not necessarily about the traditional religious meaning of the expression.

Duffy, R. D., Autin, K. L., Allan, B. A., & Douglass, R. P. (2014). Assessing work as a calling: An evaluation of instruments and practice recommendations. Journal of Career Assessment. doi: 10.1177/1069072714547163

Duffy, R. D., & Autin, K. L. (2013). Disentangling the link between perceiving a calling and living a calling. Journal of Counseling Psychology, 60(2), 219-227. doi: 10.1037/a0031934

Dik, B. J., Eldridge, B. M., Steger, M. F., & Duffy, R. D. (2012). Development and validation of the Calling and Vocation Questionnaire (CVQ) and Brief Calling Scale (BCS). Journal of Career Assessment, 20(3), 242-263. doi: 10.1177/1069072711434410

you can try this reference as well: it provides the dimensions for meaning of work from Budd (2011).

Budd, J. W., & Spencer, D. A. (2015). Worker well-being and the importance of work: bridging the gap. European Journal of Industrial Relations, 21(2), 181-196.

There is research on this topic in meaning-centered pyychotherapy according to Viktor Frankl (logotherapy and existential analysis).

Acceptance and Commitment Training/Contextual Behavioral Science explores meaning/values at work

 You could also try this reference:

May, Douglas R., Richard L. Gilson, and Lynn M. Harter. "The psychological conditions of meaningfulness, safety and availability and the engagement of the human spirit at work." Journal of occupational and organizational psychology 77.1 (2004): 11-37.