Problem	Cause	Solution
Weak or no Staining	1. Low concentration of specific oligosaccharide on sample. 2. Low concentration of lectin conjugate. 3. Insufficient incubation time. 4. Photobleaching	Causes #1 - #3 a. Increase incubation time. b. Increase concentration of conjugate. a. Avoid exposure to light.
High Background	1. Lectin conjugate is too concentrated. 2. Insufficient washing. 3. Autofluorescent sample.	a. Decrease concentration of respective reagents. b. Shorten incubation time. a. Perform multiple washings and increase washing time. a. Perform multiple washings and prolong washing time. a. Use fluorochrome with different excitation and emission spectrum. b. Use a different lectin conjugate (enzyme or colloidal gold).
Unexpected Staining Pattern	Multiple causes	a. Perform control reactions. b. Use other cytochemical techniques to prove or disprove finding.